But Westgate is not alone in wondering just how bad things can get for the stainless steel alloying agent.
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Right now, nickel's fortunes are still beholden first and foremost to its usage as an alloying agent in stainless steel.
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Around two thirds of that metal was absorbed by the stainless steel industry, which uses it as a key alloying agent.
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Silicon metal is used by aluminum producers as an alloying agent and by the chemical industry to produce chemicals known as silicones.
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Most of the world's nickel production — about 22015 percent of it — is used as an alloying input in the production of stainless steel.
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Lee Kee Group, a subsidiary of Lee Kee Holdings, also includes a futures brokerage and a consultancy, as well as alloying and assaying arms.
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In addition to alloying aluminum, the magnesium gathered in this process is used for auto parts, steel production, pharmaceuticals, fireworks, aircraft avoidance, and more.
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This form of the alloying metal is not particularly favored by industrial users because most have to cut it into more manageable size before transforming it into an intermediate product.
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Today she runs her own atelier, tucked away in a nondescript office building off Fifth Avenue, where she and a small team of artisans execute numerous metalsmithing techniques by hand: alloying, forging, chain-weaving, hammering and planishing, and stone-setting.
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Solid solution strengthening is a type of alloying that can be used to improve the strength of a pure metal. The technique works by adding atoms of one element (the alloying element) to the crystalline lattice of another element (the base metal), forming a solid solution. The local nonuniformity in the lattice due to the alloying element makes plastic deformation more difficult by impeding dislocation motion through stress fields. In contrast, alloying beyond the solubility limit can form a second phase, leading to strengthening via other mechanisms (e.g.
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Alloying of the solid metal alters its LME. Some alloying elements may increase the severity while others may prevent LME. The action of the alloying element is known to be segregation to grain boundaries of the solid metal and alteration of the grain boundary properties. Accordingly, maximum LME is seen in cases where alloy additions elements have saturated the grain boundaries of the solid metal.
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One consideration that should be avoided is powder contamination. Alloying during high-energy milling.
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The wider region has remained at the forefront of mining and steel smelting and alloying technology.
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Melting metal in a crucible for casting A metal die casting robot in an industrial foundry Melting is performed in a furnace. Virgin material, external scrap, internal scrap, and alloying elements are used to charge the furnace. Virgin material refers to commercially pure forms of the primary metal used to form a particular alloy. Alloying elements are either pure forms of an alloying element, like electrolytic nickel, or alloys of limited composition, such as ferroalloys or master alloys.
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Mechanical alloying is akin to metal powder processing, where metals may be mixed to produce superalloys. Mechanical alloying occurs in three steps. First, the alloy materials are combined in a ball mill and ground to a fine powder. A hot isostatic pressing (HIP) process is then applied to simultaneously compress and sinter the powder.
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A first glance at the composition of a steel alloy is achieved by analysing its surface with EDX-technique. Depending on the content of the alloying elements of the steel, different types of κ-carbides can form. They occur in both ferritic (α-Fe) and austenitic (γ-Fe) steels. Typical alloying elements are iron, manganese, aluminium, carbon, and silicon.
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His conclusion is based on the fact these objects contain more than 10% Arsenic, while no Arsenical alloying has been found in any other Chalcolithic artifacts.
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The effect can be substantially reduced by alloying the cast iron with nickel.Don W. Green and James O. Maloney, eds. Perry's Chemical Engineers' Handbook. 7th ed.
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Ferro molybdenum is an important iron-molybdenum metal alloy, with a molybdenum content of 60-75% It is the main source for molybdenum alloying of HSLA steel.
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The chemical composition of Mushet steel varied; tungsten was the main alloying constituent, which ranged between 4 and 12%, while manganese (2–4%) and carbon (1.5–2.5%) were the secondary alloying constituents. Typical samples contain 9% tungsten, 2.5% manganese, and 1.85% carbon. Mushet steel was harder than standard water quenched steel. It was found that Mushet steel could be best hardened by submitting it to an air blast after forging.
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MMPDS The main alloying elements are zinc (7.3–8.3%), magnesium (2.2–3.0%), copper (1.6–2.4%) and zirconium (0.05–0.15%), with traces of silicon, iron, manganese, chromium, and titanium.
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According to one source, during WW2 Russian tanks were made of a similar type of steel because of a critical lack of alloying elements such as chromium and nickel.
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Iron carbide hydrides do not appear to be stable at the conditions present in the Earth's inner core, even though carbon or hydrogen have been proposed as alloying light elements in the core.
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Tungsten steel is any steel that has tungsten as its alloying element with characteristics derived mostly from the presence of this element (as opposed to any other element in the alloy). Common alloys have between 2% and 18% tungsten by weight along with small amounts of molybdenum and vanadium which together create an alloy with exceptional heat, corrosion, and wear resistance. Tungsten is one of the oldest elements used for alloying steel. It forms a very hard carbide and iron tungstite.
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Alloys containing palladium or nickel are also important in commercial jewelry as these produce white gold alloys. Fourteen-karat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges. Fourteen- and eighteen-karat gold alloys with silver alone appear greenish- yellow and are referred to as green gold. Blue gold can be made by alloying with iron, and purple gold can be made by alloying with aluminium.
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Substitutional solute in lattice Depending on the size of the alloying element, a substitutional solid solution or an interstitial solid solution can form. In both cases, the overall crystal structure is essentially unchanged. Substitutional solid solution strengthening occurs when the solute atom is large enough that it can replace solvent atoms in their lattice positions. Some alloying elements are only soluble in small amounts, whereas some solvent and solute pairs form a solution over the whole range of binary compositions.
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In some cases, the residual atomising gas in pores may react with alloying elements to form allegedly beneficial phases e.g. N2 reacting with titanium in nickel superalloy Rene 80 to form a dispersion of TiN.
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The proper amount of thermite with alloying metal is placed in a refractory crucible, and when the rails have reached a sufficient temperature, the thermite is ignited and allowed to react to completion (allowing time for any alloying metal to fully melt and mix, yielding the desired molten steel or alloy). The reaction crucible is then tapped at the bottom. Modern crucibles have a self-tapping thimble in the pouring nozzle. The molten steel flows into the mould, fusing with the rail ends and forming the weld.
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Lithium, sodium and calcium are common impurities in aluminium alloys, which can have adverse effects on the structural integrity of castings. Conversely, otherwise pure-metals that simply contain unwanted impurities are often called "impure metals" and are not usually referred to as alloys. Oxygen, present in the air, readily combines with most metals to form metal oxides; especially at higher temperatures encountered during alloying. Great care is often taken during the alloying process to remove excess impurities, using fluxes, chemical additives, or other methods of extractive metallurgy.
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The large plates in the background are made of aluminium bronze Aluminium bronze is a type of bronze in which aluminium is the main alloying metal added to copper, in contrast to standard bronze (copper and tin) or brass (copper and zinc). A variety of aluminium bronzes of differing compositions have found industrial use, with most ranging from 5% to 11% aluminium by weight, the remaining mass being copper; other alloying agents such as iron, nickel, manganese, and silicon are also sometimes added to aluminium bronzes.
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Mechanical alloying/milling (MA/MM) performed in a high-energy ball mill such as a shaker mill or planetary mill will also induce severe plastic deformation in metals. During milling, particles are fractured and cold welded together, resulting in large deformations. The end product is generally a powder that must then be consolidated in some way (often using other SPD processes), but some alloys have the ability to consolidate in-situ during milling. Mechanical alloying also allows powders of different metals to be alloyed together during processing.
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It has long been established that the addition of alloying elements significantly lowers the SFE of most metals.Venables, J. A. (1964). The electron microscopy of deformation twinning. Journal of physics and chemistry solids, 25, 685-690.
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Stone-Miller, p. 40 The portable art associated with this time included sophisticated metalworking, including alloying of metals and soldering.Stone-Miller, p. 44 Textiles found at sites like Karwa clearly depict Chavín cultural influences,Stone-Miller, p.
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When Bangjja brassware is made, a mass of alloy of copper and tin is heated with fire and gets hammered several times. The proportion of tin in Bangjja brassware is very high compared to general bronze bowls. First of all, mass of brass nugget is made by alloying copper and tin in ratio of 78:22, which is a golden ratio which permits no error at all. This alloying ratio is not possible in modern metallographic study because in today's practical products, the proportion of tin must be under 10 percent.
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Currently, there is no visible correlation between any specific alloying tradition and the spatial distribution of finds, as well. Similar objects made of arsenical coppers and of tin bronze were found in the same geographic region and identical objects with similar metal composition were found in distant areas like Palestine and Upper Egypt. The difference in the overall alloying pattern curve in Jericho and in Tell El- Dab'a shown by Philip (1995)Philip, G. 1995. The same but different: a comparison of Middle Bronze Age metalwork from Jericho and Tall ad-Dab’a.
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Alloying a metal is done by combining it with one or more other elements. The most common and oldest alloying process is performed by heating the base metal beyond its melting point and then dissolving the solutes into the molten liquid, which may be possible even if the melting point of the solute is far greater than that of the base. For example, in its liquid state, titanium is a very strong solvent capable of dissolving most metals and elements. In addition, it readily absorbs gases like oxygen and burns in the presence of nitrogen.
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Since no arc or combustion is used, the temperature of the material is no higher than required to melt it; this can prevent loss of valuable alloying elements.Phillip F. Ostwald, Jairo Muñoz, Manufacturing Processes and Systems (9th Edition), John Wiley & Sons, 1997 page 48 The one major drawback to induction furnace usage in a foundry is the lack of refining capacity; charge materials must be clean of oxidation products and of a known composition and some alloying elements may be lost due to oxidation (and must be re-added to the melt).
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Powder metallurgy is a class of modern processing techniques in which metals are first converted into a powder form, and then formed into the desired shape by heating below the melting point. This is in contrast to casting, which occurs with molten metal. Superalloy manufacturing often employs powder metallurgy because of its material efficiency - typically much less waste metal must be machined away from the final product—and its ability to facilitate mechanical alloying. Mechanical alloying is a process by which reinforcing particles are incorporated into the superalloy matrix material by repeated fracture and welding.
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He received his M.S. in 1916 and his Ph.D. in 1919 both from Ohio State. His written works include Functions of the Alloying Elements in Steel, published by ASM International. He died on November 27, 1971 in Edgeworth, Pennsylvania.
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AerMet alloy is an ultra-high strength type of martensitic. alloy steel. The main alloying elements are cobalt and nickel, but chromium, molybdenum and carbon are also added. Its exceptional properties are hardness, tensile strength, fracture toughness and ductility.
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421, 423; Gray 2009, p. 23 They and their compounds are used as (or in) alloying components, biological agents (toxicological, nutritional, and medicinal), catalysts, flame retardants, glasses (oxide and metallic), optical storage media and optoelectronics, pyrotechnics, semiconductors, and electronics.
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Electrospark deposition is a micro-welding manufacturing process typically used to repair damage to precision or valuable mechanical components such as injection moulding tools. This process may also be referred to as "spark hardening", "electrospark toughening" or "electrospark alloying".
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Many alloys of industrial significance have some volume fraction of second phase particles, either as a result of impurities or from deliberate alloying additions. Depending on their size and distribution such particles may act to either encourage or retard recrystallization.
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1\. Bhadeshia, H. K. D. H. Recrystallisation of practical mechanically alloyed iron-based and nickel-base superalloys, Mater. Sci. Eng. A223, 64-77 (1997) 2\. P. R. Soni, Mechanical Alloying: Fundamentals and Applications, Cambridge Int Science Publishing, 2000 - Science - 151 pages.
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Rehren and Martinon Torres 2008, pp. 170–5 It was eventually replaced by speltering, the direct alloying of copper and zinc metal which was introduced to Europe in the 16th century. Brass has sometimes historically been referred to as "yellow copper".
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Indian Mounds of Wisconsin. (Madison, Univ Wisconsin Press. 2000.) pp.75-77. The evidence of smelting or alloying that has been found is subject to some dispute and a common assumption by archaeologists is that objects were cold-worked into shape.
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Such problems can be intermittent as the powdered particles of tin move around. Tin pest can be avoided by alloying with small amounts of electropositive metals or semimetals soluble in tin's solid phase, e.g. antimony or bismuth, which prevent the decomposition.
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Solid-state processes do not involve melting or evaporating the material and are typically done at relatively low temperatures. Examples of solid state processes include mechanical alloying using a high-energy ball mill and certain types of severe plastic deformation processes.
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Current research focuses on investigating alloying and low dimensional geometries to mitigate mechanical stress during lithiation. Alloying tin with elements that do not react with lithium, such as copper, has been shown to reduce stress. As for low dimensional applications, thin films have been produced with discharge capacities of 1127 mAhg−1 with excess capacity assigned to lithium ion storage at grain boundaries and associated with defect sites. Other approaches include making nanocomposites with Cu6Sn5 at its core with a nonreactive outer shell, SnO2-c hybrids have been shown to be effective, to accommodate volume changes and overall stability over cycles.
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460 In these early manufacturing operations, iron was extracted by hand from metal sponge following reduction and was then reintroduced as a powder for final melting or sintering. A much wider range of products can be obtained from powder processes than from direct alloying of fused materials. In melting operations the "phase rule" applies to all pure and combined elements and strictly dictates the distribution of liquid and solid phases which can exist for specific compositions. In addition, whole body melting of starting materials is required for alloying, thus imposing unwelcome chemical, thermal, and containment constraints on manufacturing.
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The introduction of atom1 into a crystal of atom2 creates a pinning point for multiple reasons. An alloying atom is by nature a point defect, thus it must create a stress field when placed into a foreign crystallographic position, which could block the passage of a dislocation. However, it is possible that the alloying material is approximately the same size as the atom that is replaced, and thus its presence would not stress the lattice (as occurs in cobalt alloyed nickel). The different atom would, though, have a different elastic modulus, which would create a different terrain for the moving dislocation.
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One of the metals employed is black, made by alloying copper and tin with small amounts of gold and silver, and then "pickling" it in organic acid. This black metal is possibly a variety of the "Corinthian bronze" described by Pliny and Plutarch.
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1–4 K; mixing the two phases allows obtaining intermediate TC values. The TC value can also be raised by alloying tungsten with another metal (e.g. 7.9 K for W-Tc). Such tungsten alloys are sometimes used in low-temperature superconducting circuits.
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Cadmium is classified as an IARC Group 1 carcinogen and it is a cause of several cancers, including lung cancer. Workers can be exposed to cadmium through welding, zinc smelting, copper smelting, lead smelting, electroplating, battery manufacture, plastics manufacture, and in alloying.
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Brazing has the advantage of producing less thermal stresses than welding, and brazed assemblies tend to be more ductile than weldments because alloying elements can not segregate and precipitate. Brazing techniques include, flame brazing, resistance brazing, furnace brazing, diffusion brazing, inductive brazing and vacuum brazing.
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Suryanarayana C. Mechanical alloying and milling, Progress in Materials Science 46 (2001) 1-184 The embrittlement of the sample makes even elastic and soft samples grindable. Tolerances less than 5 µm can be achieved. The ground material can be analyzed by a laboratory analyzer.
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In 1836, John Daniell invented a primary cell which solved the problem of polarization by eliminating hydrogen gas generation at the positive electrode. Later results revealed that alloying the amalgamated zinc with mercury would produce a higher voltage. Swedish chemist Svante Arrhenius portrait circa 1880s.
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Alloying the lead with tin or antimony to harden it makes this nearly impossible. Use of hard alloys typically leads to poor accuracy. Benet cup and Martin-type primers were later replaced by more reliable Boxer type primers. The ballistic performance of the original .
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Unlike VLS, the catalytic seed remains in solid state when subjected to high temperature annealing of the substrate. This such type of synthesis is widely used to synthesise metal silicide/germanide nanowires through VSS alloying between a copper substrate and a silicon/germanium precursor.
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Thoma's research interests include 3D printing technology, additive manufacturing, materials processing, and alloying theory. Thoma has received a number of honors and awards, including the 2010 Distinguished Achievement Award from the College of Engineering at the University of Wisconsin–Madison, and 2019 TMS Fellow Award.
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Johari, O., Thomas, G., (1964). Substrates in explosively deformed Cu and CU-Al alloys. Acta Metallurgica 12, (10), 1153-1159. Stacking fault energy is heavily influenced by a few major factors, specifically base metal, alloying metals, percent of alloy metals, and valence-electron to atom ratio.
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A low chromium, nickel–molybdenum alloy, Hastelloy-N, was used in the MSRE and proved compatible with the fluoride salts FLiBe and FLiNaK.DeVan, Jackson H. "Effect of Alloying Additions on Corrosion Behavior of Nickel–Molybdenum Alloys in Fused Fluoride Mixtures." Thesis. University of Tennessee, 1960. Web. <>.
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Another commonly used measure is the reduction of area at fracture q.Dieter, G. (1986) Mechanical Metallurgy, McGraw-Hill, The ductility of steel varies depending on the alloying constituents. Increasing the levels of carbon decreases ductility. Many plastics and amorphous solids, such as Play-Doh, are also malleable.
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Essar Steel Algoma from Wallace Terr., Sault Ste. Marie Algoma currently has a capacity of 4 million tons per year. Primary steel making facilities include two blast furnaces, three coke batteries, two, 260 short ton basic oxygen furnaces, with two ladle metallurgy stations for refining and alloying.
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Therefore, steel has the best machinability with medium amounts of carbon, about 0.20%. Chromium, molybdenum and other alloying metals are often added to steel to improve its strength. However, most of these metals also decrease machinability. Inclusions in steel, especially oxides, may abrade the cutting tool.
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AA 6063 is an aluminium alloy, with magnesium and silicon as the alloying elements. The standard controlling its composition is maintained by The Aluminum Association. It has generally good mechanical properties and is heat treatable and weldable. It is similar to the British aluminium alloy HE9.
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Varying the amount of hydrogen and other alloying elements, and their form in the chromium hydride either as solute elements, or as precipitated phases, expedites the movement of dislocations in chromium, and thus controls qualities such as the hardness, ductility, and tensile strength of the resulting chromium hydride.
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Aluminium alloy parts are anodized to greatly increase the thickness of this layer for corrosion resistance. The corrosion resistance of aluminium alloys is significantly decreased by certain alloying elements or impurities: copper, iron, and silicon,. so 2000-, 4000-, 6000 and 7000-series Al alloys tend to be most susceptible.
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The pigment is a nontoxic alternative to cadmium sulfide pigments. Cerium is used as alloying element in aluminum to create castable eutectic alloys, Al-Ce alloys with 6–16 wt.% Ce, to which Mg and/or Si can be further added; these alloys have excellent high temperature strength.
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The component metals can be purified in an electron beam furnace or the alloy can be used as it is. For alloying with steel the ferroniobium is added to molten steel before casting. The largest producers of ferroniobium are the same as for niobium and are located in Brazil and Canada.
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Metals with fine grain structure before melting provide superior wetting to metals with large grains. Alloying additives (e.g. strontium to aluminium) can be added to refine grain structure, and the preforms or foils can be prepared by rapid quenching. Very rapid quenching may provide amorphous metal structure, which possess further advantages.
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Pure lead is undesirably soft for casting bullets not requiring such expansion. Tin is a common alloying element. Lead alloyed with a small amount of tin fills out moulds more uniformly than pure lead. Tin also increases the hardness of cast bullets up to a maximum at about eight to ten percent tin.
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Oxide may also be grown with impurities (alloying or "doping"). This may have two purposes. During further process steps that occur at high temperature, the impurities may diffuse from the oxide into adjacent layers (most notably silicon) and dope them. Oxides containing 5–15% impurities by mass are often used for this purpose.
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Ryaztsvetmet produces pure lead (99.97% and 99.985%) and antimony and tin based lead alloys, as well as custom-made lead alloys with alloying additions. Ryaztsvetmet offers a selection of lead powder and feathered tin, solder alloys, Babbitts, lead pipes and goods (anodes & wires) The plant also sells crushed polypropylene (from discarded automotive batteries).
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Oxygen passivates Se vacancies that act as compensating donors and recombination centers. Alloying CIS (CuInSe2) with CGS (CuGaSe2) increases the bandgap. To reach the ideal bandgap for a single junction solar cell, 1.5 eV, a Ga/(In+Ga) ratio of roughly 0.7 is optimal. However, at ratios above ~0.3, device performance drops off.
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Scandium and gadolinium have been tried as alloying elements; an alloy with 1% manganese, 0.3% scandium and 5% gadolinium offers almost perfect creep resistance at 350C. The physical composition of these multi-component alloys is complicated, with plates of intermetallic compounds such as Mn2Sc forming. Erbium has also been considered as an additive.
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Hopewell copper falcon, ca. 200 BCE-1 CE, Ohio"Falcon-shaped Cut-Out." Ohio Pix. (retrieved 12 July 2011) Malden, Etowah and Spiro Moundville Archaeological evidence has not revealed metal smelting or alloying of metals by pre-Columbian native peoples north of the Rio Grande; however, they did use native copper extensively.
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The Bronze Age was a period in civilisation's development when the most advanced metalworking consisted of techniques for smelting copper and tin from naturally occurring outcroppings of ore, and then alloying those metals to cast bronze. There are claims of an earlier appearance of tin bronze in Thailand in the 5th millennium BCE.
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Changes in density, alloying, and heat treatments can alter the physical characteristics of various products. For instance, the Young's modulus En of sintered iron powders remains somewhat insensitive to sintering time, alloying, or particle size in the original powder for lower sintering temperatures, but depends upon the density of the final product: E_n/E = (D/d)^{3.4} where D is the density, E is Young's modulus and d is the maximum density of iron. Sintering is static when a metal powder under certain external conditions may exhibit coalescence, and yet reverts to its normal behavior when such conditions are removed. In most cases, the density of a collection of grains increases as material flows into voids, causing a decrease in overall volume.
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Visual evidence of aluminum alloying into < 1 1 1 > silicon is due to excessive aluminum annealing. The integrated circuit aluminum layer was removed via chemical etching to reveal this detail. A metal gate, in the context of a lateral metal-oxide-semiconductor (MOS) stack, is just that—the gate material is made from a metal.
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The superlattice of palladium-copper system is used in high performance alloys to enable a higher electrical conductivity, which is favored by the ordered structure. Further alloying elements like silver, rhenium, rhodium and ruthenium are added for better mechanical strength and high temperature stability. This alloy is used for probe needles in probe cards.
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The archeological evidence of smelting or alloying is subject to some dispute, and it is commonly believed that objects were cold-worked into shape. Artifacts from some of these sites have been dated from 4000 to 1000 BCE.Pleger, Thomas C. "Old copper and red ocher social complexity." Midcontinental Journal of Archaeology (2000): 169-190.
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The flux may consist of fluorides of calcium and oxides of calcium, magnesium, silicon, aluminium and manganese. Alloying elements may be added as per requirements. Substances evolving large amount of gases during welding are never mixed with the flux. Flux with fine and coarse particle sizes are recommended for welding heavier and smaller thickness respectively.
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As the 20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding, as advances in metal coverings (known as flux) were made.Weman, p. 26 Flux covering the electrode primarily shields the base material from impurities, but also stabilizes the arc and can add alloying components to the weld metal.
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Small catalyst particles have the highest possible relative surface area and high reaction temperature, both factors that generally increase the reactivity of a catalyst. However, these factors are also the circumstances under which sintering occurs. Specific materials may also increase the rate of sintering. On the other hand, by alloying catalysts with other materials, sintering can be reduced.
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Most rimmed steel has a carbon content below 0.25%, a manganese content below 0.6%, and is not alloyed with aluminum, silicon, and titanium. This type of steel is commonly used for cold-bending, cold-forming, cold-heading and, as the name implies, drawing. Due to the non- uniformity of alloying elements it is not recommended for hot-working applications.
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AA 7039 is an aluminum alloy principally containing zinc (3.5–4.5%) as an alloying element. It also contains 0.30% silicon, 0.40% iron, 0.10% copper, 0.10–0.40% manganese, 2.3–3.3% magnesium, 0.15–0.25% chromium, 0.10% titanium and up to 0.15% trace elements. The density of 7039 aluminium is . This alloy was first registered in 1962, in the United States.
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Bibliography of Greek coin hoards, p. 194-195 The coinage of the period, such as that of Rajuvula, tends to become very crude and barbarized in style. It is also very much debased, the silver content becoming lower and lower, in exchange for a higher proportion of bronze, an alloying technique (billon) suggesting less than wealthy finances.
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The titanium used for surface alloying of AISI304 stainless steel was CP-Ti, grade2, 300µm thick sheet.Tej Ram Sahu and Ashok Sharma. “To Perceive the Mix of GTA Parameters on the Outside of AISI304 Stainless Steel that Gives Improvement in the Properties AISI304 Tempered Steel in the Changed Layer”, United International Journal for Research & Technology 1.1 (2019): 10-26.
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A well- designed implant could provide the exact mechanical support needed for different areas (through alloying and metal working), and load would be transferred to the surrounding tissue over time, letting it heal and reducing the effects of stress shielding. A summary of the primary benefits and drawbacks of magnesium biomaterials has been provided by Kirkland.
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The electrode composition depends upon the material being welded. Alloying elements may be added in the electrodes. Electrodes are available to weld mild steels, high carbon steels, low and special alloy steels, stainless steel and some of the nonferrous of copper and nickel. Electrodes are generally copper coated to prevent rusting and to increase their electrical conductivity.
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After the blow, the liquid metal was recarburized to the desired point and other alloying materials were added, depending on the desired product. A Bessemer converter could treat a "heat" (batch of hot metal) of 5 to 30 tons at a time. They were usually operated in pairs, one being blown while another was being filled or tapped.
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Mechanical alloying (MA) is a solid-state and powder processing technique involving repeated cold welding, fracturing, and re-welding of blended powder particles in a high-energy ball mill to produce a homogeneous material. Originally developed to produce oxide-dispersion strengthened (ODS) nickel- and iron-base superalloys for applications in the aerospace industry,H. K. D. H. Bhadeshia, Practical ODS Alloys, Materials Science and Engineering A, 223 (1997)64-77 MA has now been shown to be capable of synthesizing a variety of equilibrium and non-equilibrium alloy phases starting from blended elemental or pre-alloyed powders.Suryanarayana C. Mechanical alloying and milling, Progress in Materials Science 46 (2001) 1-184 The non-equilibrium phases synthesized include supersaturated solid solutions, metastable crystalline and quasicrystalline phases, nanostructures, and amorphous alloys.
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The steel is further refined in the ladle furnace, by adding alloying materials to impart special properties required by the customer. Sometimes argon or nitrogen is bubbled into the ladle to make the alloys mix correctly. # After the steel is poured off from the BOS vessel, the slag is poured into the slag pots through the BOS vessel mouth and dumped.
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Although other elements may be present in smaller amounts, the alloying element of concern in aluminum for pistons is silicon. The point at which silicon is fully and exactly soluble in aluminum at operating temperatures is around 12%. Either more or less silicon than this will result in two separate phases in the solidified crystal structure of the metal. This is very common.
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Materials science is closely related to civil engineering. It studies fundamental characteristics of materials, and deals with ceramics such as concrete and mix asphalt concrete, strong metals such as aluminum and steel, and thermosetting polymers including polymethylmethacrylate (PMMA) and carbon fibers. Materials engineering involves protection and prevention (paints and finishes). Alloying combines two types of metals to produce another metal with desired properties.
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Tempering will cause the dissolved alloying elements to precipitate, or in the case of quenched steels, improve impact strength and ductile properties. Often, mechanical and thermal treatments are combined in what is known as thermo-mechanical treatments for better properties and more efficient processing of materials. These processes are common to high alloy special steels, super alloys and titanium alloys.
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Welding of some Inconel alloys (especially the gamma prime precipitation hardened family; e.g., Waspalloy and X-750) can be difficult due to cracking and microstructural segregation of alloying elements in the heat-affected zone. However, several alloys such as 625 and 718 have been designed to overcome these problems. The most common welding methods are gas tungsten arc welding and electron-beam welding..
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Foreign similar steels – for example, German "Low-%" Nickel Steel and U.S. High Tensile Steel (HTS) – were more complex alloys using chromium, vanadium and molybdenum. Up until about 1945, Ducol generally contained only manganese and silicon as alloying elements. More recent weldable grades (Ducol W21, W25, W30, and W30 grades A & B) include varying amounts of nickel, chromium, copper, molybdenum and vanadium.
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Microalloyed steel is a type of alloy steel that contains small amounts of alloying elements (0.05 to 0.15%), including niobium, vanadium, titanium, molybdenum, zirconium, boron, and rare-earth metals. They are used to refine the grain microstructure or facilitate precipitation hardening.Degarmo, p. 116. In terms of performance and cost, microalloyed steels are between a carbon steel and a low alloy steel.
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6061 (UNS designation A96061) is a precipitation-hardened aluminum alloy, containing magnesium and silicon as its major alloying elements. Originally called "Alloy 61S", it was developed in 1935. It has good mechanical properties, exhibits good weldability, and is very commonly extruded (second in popularity only to 6063). It is one of the most common alloys of aluminum for general-purpose use.
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Brass is an example of an alloy, being a homogeneous mixture of copper and zinc. Another example is steel, which is an alloy of iron with carbon and possibly other metals. The purpose of alloying is to produce desired properties in a metal that naturally lacks them. Brass, for example, is harder than copper and has a more gold-like color.
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Structural tubing and piping often contains molybdenum, as do many stainless steels. Its strength at high temperatures, resistance to wear and low coefficient of friction are all properties which make it invaluable as an alloying compound. Its excellent anti-friction properties lead to its incorporation in greases and oils where reliability and performance are critical. Automotive constant-velocity joints use grease containing molybdenum.
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Tungsten was discovered in 1781 by the Swedish chemist, Carl Wilhelm Scheele. Tungsten has the highest melting point of all metals, at . Filament of a 200 watt incandescent lightbulb highly magnified Up to 22% rhenium is alloyed with tungsten to improve its high temperature strength and corrosion resistance. Thorium as an alloying compound is used when electric arcs have to be established.
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Experimental archaeometallurgy is a subset of experimental archaeology that specifically involves past metallurgical processes most commonly involving the replication of copper and iron objects as well as testing the methodology behind the production of ancient metals and metal objects. Metals and elements used primarily as alloying materials, such as tin, lead, and arsenic, are also a part of experimental research.
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The main use of arsenic is in alloying with lead. Lead components in car batteries are strengthened by the presence of a very small percentage of arsenic. Dezincification of brass (a copper-zinc alloy) is greatly reduced by the addition of arsenic. "Phosphorus Deoxidized Arsenical Copper" with an arsenic content of 0.3% has an increased corrosion stability in certain environments.
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An alloy is technically an impure metal, but when referring to alloys, the term impurities usually denotes undesirable elements. Such impurities are introduced from the base metals and alloying elements, but are removed during processing. For instance, sulfur is a common impurity in steel. Sulfur combines readily with iron to form iron sulfide, which is very brittle, creating weak spots in the steel.
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It became one of the most important metals to the ancients. Around 10,000 years ago in the highlands of Anatolia (Turkey), humans learned to smelt metals such as copper and tin from ore. Around 2500 BC, people began alloying the two metals to form bronze, which was much harder than its ingredients. Tin was rare, however, being found mostly in Great Britain.
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Commercially, the chief use for the metal is as an alloying agent to make aluminium-magnesium alloys, sometimes called "magnalium" or "magnelium". Since magnesium is less dense than aluminium, these alloys are prized for their relative lightness and strength. Magnesium ions are sour to the taste, and in low concentrations help to impart a natural tartness to fresh mineral waters.
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Other seminal discoveries and contributions to the field include the defects engineering in 2D quantum materials, 2D alloying, van der Waals epitaxy growth of quantum materials, 2D anisotropic materials, the discovery of Moire excitons in 2Ds, band alignment models in 2D heterojunctions, the discovery of quintons, 2D phase change alloys, the discovery of bright/dark excitons, and the engineering of 2D anisotropic materials.
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Moreover, Nb is a strong carbide/nitride former, the Nb(C, N) formed can hinder grain growth during austenite-to-ferrite transition. Vanadium: V can significantly increase the strength and transition temperature by precipitate strengthening . Titanium: Ti have a slight increase in strengthen via both grain refinement and precipitate strengthening. Nb, V, and Ti are three common alloying elements in HSLA steels.
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Antimony compounds are prominent additives for chlorine and bromine containing fire retardants found in many commercial and domestic products. The largest application for metallic antimony is as alloying material for lead and tin. It improves the properties of the alloys which are used as in solders, bullets and ball bearings. An emerging application is the use of antimony in microelectronics.
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The high shock resistance and good hardenability are provided by chromium- tungsten, silicon-molybdenum, silicon-manganese alloying. Shock-resisting group tool steels (S) are designed to resist shock at both low and high temperatures. A low carbon content is required for the necessary toughness (approximately 0.5% carbon). Carbide-forming alloys provide the necessary abrasion resistance, hardenability, and hot-work characteristics.
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In 1942, Mr. Chan Chak Hong, grandfather of Mr. PC Chan, founded Lee Kee as a metal scrap trading company on Reclamation Street, Mongkok. Lee Kee was formally registered in 1947. In late 1950s, Hong Kong's light industries bloomed, and so did the demand for moulds. Lee Kee set up its alloying workshop to produce Lee Kee's own brand of zinc alloy.
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Alloying elements such as copper, antimony, bismuth, cadmium, and silver increase its hardness. Tin tends rather easily to form hard, brittle intermetallic phases, which are often undesirable. It does not form wide solid solution ranges in other metals in general, and few elements have appreciable solid solubility in tin. Simple eutectic systems, however, occur with bismuth, gallium, lead, thallium and zinc.
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The microhardness of BAM powders is 32–35 GPa. It can be increased to 45 GPa by alloying with Boron rich Titanium Boride, Fracture toughness can be increased with TiB2 or by depositing a quasi-amorphous BAM film. Addition of AlN or TiC to BAM reduces its hardness. By definition, a hardness value exceeding 40 GPa makes BAM a superhard material.
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Murty's Ph.D. dissertation was titled "Study of Amorphous Phase Formation by Mechanical Alloying in Ti Based Systems", in which he started one of the earliest works in Mechanical alloying in India. His research interests span over nanocrystalline metals and alloys, High entropy alloys, Bulk metallic glass, quasicrystalline alloys, grain refinement and modification of Al alloys, Al-based composites, in-situ composites, non-equilibrium processing, particulate technologies, thermodynamics and kinetics of phase transformations, transmission electron microscopy and Atom-probe tomography. He has set up a National Facility for Atom Probe Tomography at IIT Madras with a remotely operable Local Electrode Atom Probe (LEAP) (first such facility globally) that can characterize materials in 3D at the atomic scale. He has also set up Deakin-IITM Centre of Excellence on Advanced Materials and Manufacturing at IIT Madras jointly with Deakin University, Australia.
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Which element and how much is added dramatically affects the SFE of a material. The figures on the right show how the SFE of copper lowers with the addition of two different alloying elements; zinc and aluminum. In both cases, the SFE of the brass decreases with increasing alloy content. However, the SFE of the Cu-Al alloy decreases faster and reaches a lower minimum.
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Titanium powder metallurgy (P/M) offers the possibility of creating net shape or near net shape parts without the material loss and cost associated with having to machine intricate components from wrought billet. Powders can be produced by the blended elemental technique or by pre-alloying and then consolidated by metal injection moulding, hot isostatic pressing, direct powder rolling or laser engineered net shaping.
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Cathodic modification is the retardation of anodic reaction as the result of an increase in the ability of an alloy to be passivated by the introduction of an active cathode into the alloy e.g. the alloying of stainless steel and titanium with platinum group metals (1). This is one way in which corrosion resistant alloys can be produced and the resistance of alloy against electrochemical attack increased.
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2024 aluminium alloy is an aluminium alloy, with copper as the primary alloying element. It is used in applications requiring high strength to weight ratio, as well as good fatigue resistance. It is weldable only through friction welding, and has average machinability. Due to poor corrosion resistance, it is often clad with aluminium or Al-1Zn for protection, although this may reduce the fatigue strength.
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39–46, April 2006. This is mainly due to the higher electromigration activation energy levels of copper, caused by its superior electrical and thermal conductivity as well as its higher melting point. Further improvements can be achieved by alloying copper with about 1% palladium which inhibits diffusion of copper atoms along grain boundaries in the same way as the addition of copper to aluminium interconnect.
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Gold, silver, and copper are quite soft metals and so are easily damaged in daily use as coins. Precious metal may also be easily abraded and worn away through use. In their numismatic functions these metals must be alloyed with other metals to afford coins greater durability. The alloying with other metals makes the resulting coins harder, less likely to become deformed and more resistant to wear.
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Plutonium alloys can be produced by adding a metal to molten plutonium. However, if the alloying metal is sufficiently reductive, plutonium can be added in the form of oxides or halides. The δ phase plutonium–gallium and plutonium–aluminium alloys are produced by adding plutonium(III) fluoride to molten gallium or aluminium, which has the advantage of avoiding dealing directly with the highly reactive plutonium metal.
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Alloying elements are added to a base metal, to induce hardness, toughness, ductility, or other desired properties. Most metals and alloys can be work hardened by creating defects in their crystal structure. These defects are created during plastic deformation by hammering, bending, extruding, et cetera, and are permanent unless the metal is recrystallized. Otherwise, some alloys can also have their properties altered by heat treatment.
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Zirconium is mainly used as a refractory and opacifier, although minor amounts are used as alloying agent for its strong resistance to corrosion. Zirconium is obtained mainly from the mineral zircon, which is the most important form of zirconium in use. Zirconium forms a variety of inorganic and organometallic compounds such as zirconium dioxide and zirconocene dichloride, respectively. Five isotopes occur naturally, three of which are stable.
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AA 2519 is an aluminium alloy principally containing copper (5.3–6.4%) as an alloying element. It also contains 0.25% silicon, 0.30% iron, 0.10–0.50% manganese, 0.05–0.40% magnesium, 0.10% zinc, 0.02–0.10% titanium, 0.05–0.15% vanadium, 0.10–0.25% zirconium, 0.40% silicon-iron compounds, and up to 0.15% trace elements. The density of 2519 aluminium is . It was first registered in 1985, in the United States.
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Long-term exposure to beryllium may result in shortness of breath, chronic cough, and significant weight loss, accompanied by fatigue and general weakness. Other alloying elements such as arsenic, manganese, silver, and aluminium can cause sickness to those who are exposed. More common are the anti-rust coatings on many manufactured metal components. Zinc, cadmium, and fluorides are often used to protect irons and steels from oxidizing.
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Attempts were made to separate plutonium from uranium through metallurgy, exploiting plutonium's greater affinity with gold and silver, but the Manhattan Project chose to use the bismuth phosphate process, a chemical separation method, instead. The Ames Project also studied thorium, alloying it with bismuth, carbon, chromium, iron, manganese, molybdenum, nickel, oxygen, tin, tungsten and uranium, and alloyed beryllium with bismuth, lead, thorium, uranium and zinc.
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Its first applications were developed in the late 19th century. Thorium's radioactivity was widely acknowledged during the first decades of the 20th century. In the second half of the century, thorium was replaced in many uses due to concerns about its radioactivity. Thorium is still being used as an alloying element in TIG welding electrodes but is slowly being replaced in the field with different compositions.
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Chromite can be used as a refractory material, because it has a high heat stability. The chromium extracted from chromite is used in chrome plating and alloying for production of corrosion resistant superalloys, nichrome, and stainless steel. Chromium is used as a pigment for glass, glazes, and paint, and as an oxidizing agent for tanning leather. It is also sometimes used as a gemstone.
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Chromite is the source of chromium used commercially and as an alloying element plays an important role in metallurgy. Balochistan is endowed with huge reserves of chromite. The first discovery was made at Muslim Bagh and Khanozai in district Kila Saifullah in 1901. Muslim Bagh deposits were first discovered by Vredenburg during the same period in the course of regional reconnaissance mapping of the province.
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In Period IVB (3100-2700 B.C.), a copper-bronze dagger was found which contained 3.0% tin, seemingly representing an alloy of tin. This is a very early evidence for copper-tin alloying in southwestern Asia. A related site is Tal-i Iblis, where early metallurgy has also been attested.C. C. Lamberg-Karlovsky (1971), The Early Bronze Age of Iran as seen from Tepe Yahya.
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Recently, gold atoms were recognized as a highly efficient healing agents in Fe-based alloys. A defect-induced mechanism is indicated for the Au precipitation, i.e. the Au solute remains dissolved until defects are formed. Autonomous repair of high-temperature creep damage was reported by alloying with a small amount of Au. Healing agents selectively precipitate at the free surface of a creep cavity, resulting in pore filling.
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Amorphous metals are produced in several ways, including extremely rapid cooling, physical vapor deposition, solid-state reaction, ion irradiation, and mechanical alloying. The first reported metallic glass was an alloy (Au75Si25) produced at Caltech in 1960. More recently, batches of amorphous steel with three times the strength of conventional steel alloys have been produced. Currently the most important applications rely on the special magnetic properties of some ferromagnetic metallic glasses.
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For example, the artifact shape, cracks, and places where pieces of metal were joined together can be identified. Additionally, one garner information pretianing to casting errors, mould seams and decorative work. Metallography exams the size and shape of the grains of minerals in the materials for traces of heating, working and alloying. Scanning electron microscopes are also utilized to explore manufacturing techniques used for jewellery and weapons making.
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Buschowl, K.H.J. et al. ed. (2001) Encyclopedia of Materials:Science and Technology. Elsevier. pp. 4807–4808. However, the grain structure hardens and embrittles the metal; this change adversely affects the workability of the material, especially when rolling it. When alloying, contamination must be kept low, as carbides, sulfides, oxides and nitrides, even in particles as small as one micrometer in diameter, increase hysteresis losses while also decreasing magnetic permeability.
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Inlays are the result of combining or two or more metals into one ring. It is not to be confused with alloying. The process of inlaying involves crushing the metals into channels, which are then trapped under pressure. On a ring, this usually results in metals sitting side-by-side on the surface – for example, a strip of gold running through the middle of an otherwise titanium ring.
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An 1889 newspaper advertisement for "arsenic complexion wafers". Arsenic was known to be poisonous during the Victorian era. Beginning in about 3000 BC arsenic was mined and added to copper in the alloying of bronze, but the adverse health effects of working with arsenic led to it being abandoned when a viable alternative, tin, was discovered. In addition to its presence as a poison, for centuries arsenic was used medicinally.
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Narygina and others estimate 0.5–1.0% (weight) of hydrogen in the melt. Similar, but without extrapolations in pressure, theoretical estimates give a narrower range of concentrations 0.4-0.5% (weight), however, this results to too low mean atomic mass of the inner core (43.8-46.5) and hydrogen seems to be less likely than other elements (S, Si, C, O) to be the main light alloying element in the core.
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Ferroniobium is an important iron-niobium alloy, with a niobium content of 60-70%. It is the main source for niobium alloying of HSLA steel and covers more than 80% of the worldwide niobium production. The niobium is mined from pyrochlore deposits and is subsequently transformed into the niobium pentoxide Nb2O5. This oxide is mixed with iron oxide and aluminium and is reduced in an aluminothermic reaction to niobium and iron.
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Many elements are often alloyed with steel. The main purpose for alloying most elements with steel is to increase its hardenability and to decrease softening under temperature. Tool steels, for example, may have elements like chromium or vanadium added to increase both toughness and strength, which is necessary for things like wrenches and screwdrivers. On the other hand, drill bits and rotary files need to retain their hardness at high temperatures.
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The modern X-ray fluorescence is also a non-destructive technique that is suitable for normal assaying requirements. It typically has an accuracy of 2–5 parts per thousand and is well-suited to the relatively flat and large surfaces. It is a quick technique taking about three minutes, and the results can be automatically printed out by the computer. It also measures the content of the other alloying metals present.
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Alloying of zirconium-bearing materials has been a major problem in their development. It is usual to add the zirconium from a salt—and careful control can produce good results. Dominion Magnesium Limited in Canada have developed a method adding in the conventional manner through a master alloy. Explanation for the low extrusion rates necessary to successfully extrude some magnesium alloys does not lie outside reasons put forward for other metals.
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These elements are small enough to fit between normal crystalline lattice locations. In contrast, those elements that replace locations in the crystalline structure are called substitutional elements.Influence of Interstitial and Some Substitutional Alloying Elements An example of the effects of interstitial elements on metal properties can be found in grade 1–4 titanium. Although the grades 1–4 are considered commercially "pure" they have varying tensile strength among other differences.
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AA 2319 (UNS A92319) is an aluminium alloy principally containing copper (5.8–6.8%) as an alloying element. It also contains ≤0.20% silicon, ≤0.30% iron, 0.20–0.40% manganese, ≤0.02% magnesium, ≤0.10% zinc, 0.10–0.20% titanium, 0.05–0.15% vanadium, 0.10–0.25% zirconium, ≤0.0003% beryllium (in arc welding electrodes) and up to 0.15% trace elements. The density of 2319 aluminium is . This alloy was first registered in 1958, in the United States.
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Using the torque shaft was the result of being forced to use the Corvair underbody which, being a rear engine platform, had no drive shaft tunnel. To combine flexibility with strength in the proper proportion, the shaft was forged of SAE 8660 steel (high nickel, chrome and molybdenum alloying percentages) for torsion bar specifications. For automatic cars, the shaft was in diameter and long, while the manual-box shaft was by .
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Notably, certain artifacts from West Mexico contain tin or arsenic at concentrations as high as 23 weight percent, while concentrations of alloying elements at roughly 2 to 5 weight percent are typically adequate for augmented strength and mechanical utility.Hosler 1988, 1995. Metal smiths in pre-Columbian West Mexico particularly exploited the brilliance inherent in metallic sound and sheen, suggesting that their creations tended to occupy a sacred and symbolic space.Hosler 1995.
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Synthesis of chromium carbide can be achieved through mechanical alloying. In this type of process metallic chromium and pure carbon in the form of graphite are loaded into a ball mill and ground into a fine powder. After the components have been ground they are pressed into a pellet and subjected to hot isostatic pressing. Hot isostatic pressing utilizes an inert gas, primarily argon, in a sealed oven.
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Arabic al-kīmiyaʾ or al-khīmiyaʾ ( or ), according to some, is thought to derive from the Koine Greek word khymeia () meaning "the art of alloying metals, alchemy"; in the manuscripts, this word is also written khēmeia () or kheimeia (),Cf. Liddell-Scott-Jones s.v. . which is the probable basis of the Arabic form. According to Mahn, the Greek word χυμεία khumeia originally meant "pouring together", "casting together", "weld", "alloy", etc. (cf.
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Maraging steels (a portmanteau of "martensitic" and "aging") are steels (iron alloys) that are known for possessing superior strength and toughness without losing ductility. Aging refers to the extended heat-treatment process. These steels are a special class of low-carbon ultra-high-strength steels that derive their strength not from carbon, but from precipitation of intermetallic compounds. The principal alloying element is 15 to 25 wt% nickel.
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This increases the chance of contamination from any contacting surface, and so must be melted in vacuum induction-heating and special, water-cooled, copper crucibles.Metals Handbook: Properties and selection By ASM International – ASM International 1978 Page 407 However, some metals and solutes, such as iron and carbon, have very high melting-points and were impossible for ancient people to melt. Thus, alloying (in particular, interstitial alloying) may also be performed with one or more constituents in a gaseous state, such as found in a blast furnace to make pig iron (liquid-gas), nitriding, carbonitriding or other forms of case hardening (solid-gas), or the cementation process used to make blister steel (solid-gas). It may also be done with one, more, or all of the constituents in the solid state, such as found in ancient methods of pattern welding (solid-solid), shear steel (solid-solid), or crucible steel production (solid-liquid), mixing the elements via solid-state diffusion.
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Often the presence, absence, or variation of minute quantities of secondary elements and compounds in a bulk material will greatly affect the final properties of the materials produced. For example, steels are classified based on 1/10 and 1/100 weight percentages of the carbon and other alloying elements they contain. Thus, the extracting and purifying methods used to extract iron in a blast furnace can affect the quality of steel that is produced.
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In general, gas carburizing is used for parts that are large. Liquid carburizing is used for small and medium parts and pack carburizing can be used for large parts and individual processing of small parts in bulk. Vacuum carburizing (low pressure carburizing or LPC) can be applied across a large spectrum of parts when used in conjunction with either oil or high pressure gas quenching (HPGQ), depending on the alloying elements within the base material.
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Edgar Collins Bain (September 14, 1891 - November 27, 1971) was an American metallurgist and member of the National Academy of Sciences, who worked for the US Steel Corporation of Pittsburgh, Pennsylvania. He worked on the alloying and heat treatment of steel; Bainite is named in his honor. He was born near LaRue, Ohio to Milton Henry (of Scottish descent) and Alice Anne Collins Bain. He graduated with a B.S. from Ohio State University in 1912.
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Later reactor fuel could consist of other mixtures and varying enrichments of uranium and plutonium and could use other alloying metals in place of zirconium. There are no power generating facilities planned for the VTR. GE Hitachi and TerraPower, a Washington state-based nuclear company co-founded by Bill Gates, recently joined together to pursue a public-private partnership to construct the Versatile Test Reactor for the U.S. Department of Energy at Idaho National Laboratory.
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The firm's largest asset is its 45% share in the intellectual property of T-Steel. The basic product is a combination of highly specialized processes and alloying technologies invented over 30 years ago in Hungary. The technology is based on the modification of the metallurgical properties of steel at a molecular level. The result is a product that Astra claims is stronger, less expensive, and uses less raw materials to make than conventional steel.
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As changing designs required larger pressure vessels, the addition of nickel to this alloy by roughly 0.4-0.7 wt% was required to increase the yield strength. Other common steel alloys include SA-533 Grade B Class 1 and SA-508 Class 2. Both materials have main alloying elements of nickel, manganese, molybdenum, and silicon, but the latter also includes 0.25-0.45 wt% chromium. All alloys listed in the reference also have >0.04 wt% sulfur.
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The Auditors Court (Tribunal de Contas) is the single court of its order. It has both pure court functions (namely the supervision of the legality of the public expenses and the judging of public accounting) and also advising functions (namely to give opinion about the State accounts, alloying the Parliament to analyze them and decide). The judges of the Auditors Court are chosen through civil service examination and have the title of conselheiros (counselors).
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Annealing is the process of heating the iron-hydrogen alloy to a sufficiently high temperature to relieve local internal stresses. It does not create a general softening of the product but only locally relieves strains and stresses locked up within the material. Annealing goes through three phases: recovery, recrystallisation, and grain growth. The temperature required to anneal a particular iron hydride depends on the type of annealing to be achieved and the alloying constituents.
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Ferrouranium is used as a deoxidizer (more powerful than ferrovanadium), for denitrogenizing steel, for forming carbides, and as an alloying element. In ferrous alloys, uranium increases the elastic limit and the tensile strength. In high speed steels, it has been used to increase toughness and strength in amounts between 0.05–5%. Uranium-alloyed steels can be used at very low temperatures; nickel-uranium alloys are resistant to even very aggressive chemicals, including aqua regia.
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Nitinol biocompatibility is an important factor in biomedical applications. Nitinol (NiTi), which is formed by alloying nickel and titanium (~ 50% Ni), is a shape memory alloy with superelastic properties more similar to that of bone, when compared to stainless steel, another commonly used biomaterial. Biomedical applications that utilize Nitinol include stents, heart valve tools, bone anchors, staples, septal defect devices and implants. It is a commonly used biomaterial especially in the development of stent technology.
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Carl von Sickingen researched platinum extensively in 1772. He succeeded in making malleable platinum by alloying it with gold, dissolving the alloy in hot aqua regia, precipitating the platinum with ammonium chloride, igniting the ammonium chloroplatinate, and hammering the resulting finely divided platinum to make it cohere. Franz Karl Achard made the first platinum crucible in 1784. He worked with the platinum by fusing it with arsenic, then later volatilizing the arsenic.
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Oxide layers can also be used to obtain blue gold from an alloy of 75% gold, 24.4% iron, and 0.6% nickel; the layer forms on heat treatment in air between 450–600 °C. A rich sapphire blue colored gold of 20–23K can also be obtained by alloying with ruthenium, rhodium and three other elements and heat-treating at 1800 °C, to form the 3–6 micrometers thick colored surface oxide layer.
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The high thermal conductivities of beryllium and beryllium oxide have led to their use in thermal management applications. When added as an alloying element to aluminium, copper (notably the alloy beryllium copper), iron or nickel beryllium improves many physical properties. Tools made of beryllium copper alloys are strong and hard and do not create sparks when they strike a steel surface. Beryllium does not form oxides until it reaches very high temperatures.
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It is used as an alloying agent in beryllium copper, which is used to make electrical components due to its high electrical and heat conductivity.Standards and properties of beryllium copper. Sheets of beryllium are used in X-ray detectors to filter out visible light and let only X-rays through. It is used as a neutron moderator in nuclear reactors because light nuclei are more effective at slowing down neutrons than heavy nuclei.
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Ferroaluminum (FeAl) is a ferroalloy, consisting of iron and aluminium. The metal usually consists of 40% to 60% aluminium and applications of ferroaluminum include the deoxidation of steel, hardfacing applications, reducing agent, thermite reactions, AlNiCo magnets, and alloying additions to welding wires and fluxes. The alloy is also known for the ability to manufacture low melting point alloys and its ability to carry out aluminothermic welding. Ferroaluminum does not currently have a CAS Registry Number.
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The addition of certain alloying elements, such as manganese and nickel, can stabilize the austenitic structure, facilitating heat-treatment of low-alloy steels. In the extreme case of austenitic stainless steel, much higher alloy content makes this structure stable even at room temperature. On the other hand, such elements as silicon, molybdenum, and chromium tend to de-stabilize austenite, raising the eutectoid temperature. Austenite is only stable above in bulk metal form.
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Iron-cementite meta-stable diagram Cast iron's properties are changed by adding various alloying elements, or alloyants. Next to carbon, silicon is the most important alloyant because it forces carbon out of solution. A low percentage of silicon allows carbon to remain in solution forming iron carbide and the production of white cast iron. A high percentage of silicon forces carbon out of solution forming graphite and the production of grey cast iron.
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Other alloying agents, manganese, chromium, molybdenum, titanium and vanadium counteracts silicon, promotes the retention of carbon, and the formation of those carbides. Nickel and copper increase strength, and machinability, but do not change the amount of graphite formed. The carbon in the form of graphite results in a softer iron, reduces shrinkage, lowers strength, and decreases density. Sulfur, largely a contaminant when present, forms iron sulfide, which prevents the formation of graphite and increases hardness.
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The use of oil quenching and air- hardening helps reduce distortion, avoiding the higher stresses caused by the quicker water quenching. More alloying elements are used in these steels, as compared to the water-hardening class. These alloys increase the steels' hardenability, and thus require a less severe quenching process and as a result are less likely to crack. They have high surface hardness and are often used to make knife blades.
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The mixing of different metal elements is known as alloying. Brass is an alloy of copper and zinc. Separating individual metals from an alloy can be difficult and may require chemical processing – making an alloy is an example of a physical change that cannot readily be undone by physical means. Alloys where mercury is one of the metals can be separated physically by melting the alloy and boiling the mercury off as a vapour.
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However, the mechanisms that lead to grain refinement in SPD are the same as those originally developed for mechanical alloying, a powder process that has been characterized as "severe plastic deformation" by authors as early as 1983. Additionally, some more recent processes such as asymmetric rolling, do result in a change in the dimensions of the workpiece, while still producing an ultrafine grain structure. The principles behind SPD have even been applied to surface treatments.
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Implantation of boron ions into metals and alloys, through ion implantation or ion beam deposition, results in a spectacular increase in surface resistance and microhardness. Laser alloying has also been successfully used for the same purpose. These borides are an alternative to diamond coated tools, and their (treated) surfaces have similar properties to those of the bulk boride. For example, rhenium diboride can be produced at ambient pressures, but is rather expensive because of rhenium.
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Although carbon remains solid at higher temperatures than tungsten, carbon sublimes at atmospheric pressure instead of melting, so it has no melting point. Tungsten has the lowest coefficient of thermal expansion of any pure metal. The low thermal expansion and high melting point and tensile strength of tungsten originate from strong covalent bonds formed between tungsten atoms by the 5d electrons. Alloying small quantities of tungsten with steel greatly increases its toughness.
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The superconductivity of amorphous metal thin films was discovered experimentally in the early 1950s by Buckel and Hilsch. For certain metallic elements the superconducting critical temperature Tc can be higher in the amorphous state (e.g. upon alloying) than in the crystalline state, and in several cases Tc increases upon increasing the structural disorder. This behavior can be understood and rationalized by considering the effect of structural disorder on the electron-phonon coupling.
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In chapter 1 of his work, Evans proposes for the first time a transitional Copper Age between the Neolithic and the Bronze Age. He adduces evidence from far- flung places such as China and the Americas to show that the smelting of copper universally preceded alloying with tin to make bronze. He does not know how to classify this fourth age. On the one hand he distinguishes it from the Bronze Age.
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Ferrosilicon Silicon ferroalloy consumption is driven by cast iron and steel production, where silicon alloys are used as deoxidizers. Some silicon metal was also used as an alloying agent with iron. On the basis of silicon content, net production of ferrosilicon and miscellaneous silicon alloys in the US was 148,000 t in 2008. China is the major supplier, which in 2008 produced more ferrosilicon (4.9 Mt) than the rest of the world combined.
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Tungsten is an important alloying element in high-speed and other tool steels, and is used to a lesser extent in some stainless and structural steels. Tungsten is often added to steel melts as ferrotungsten, which can contain up to 80% tungsten. World ferrotungsten production is dominated by China, which in 2008 exported 4,835 t (gross weight) of the alloy. Ferrotungsten is relatively expensive, with the prices around $31–44 per kilogram of contained tungsten.
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Casting bronze Common engineering metals include aluminium, chromium, copper, iron, magnesium, nickel, titanium, zinc, and silicon. These metals are most often used as alloys with the noted exception of silicon. Much effort has been placed on understanding the iron- carbon alloy system, which includes steels and cast irons. Plain carbon steels (those that contain essentially only carbon as an alloying element) are used in low-cost, high-strength applications where neither weight nor corrosion are a major concern.
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In most binary systems, alloying above a concentration given by the phase diagram will cause the formation of a second phase. A second phase can also be created by mechanical or thermal treatments. The particles that compose the second phase precipitates act as pinning points in a similar manner to solutes, though the particles are not necessarily single atoms. The dislocations in a material can interact with the precipitate atoms in one of two ways (see Figure 2).
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ZnO has a relatively large direct band gap of ~3.3 eV at room temperature. Advantages associated with a large band gap include higher breakdown voltages, ability to sustain large electric fields, lower electronic noise, and high-temperature and high- power operation. The band gap of ZnO can further be tuned to ~3–4 eV by its alloying with magnesium oxide or cadmium oxide. Most ZnO has n-type character, even in the absence of intentional doping.
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Stainless steel cutlery made from Cromargan 18/10, containing 18% chromium. The strengthening effect of forming stable metal carbides at the grain boundaries and the strong increase in corrosion resistance made chromium an important alloying material for steel. The high-speed tool steels contain between 3 and 5% chromium. Stainless steel, the primary corrosion-resistant metal alloy, is formed when chromium is introduced to iron in sufficient concentrations, usually where the chromium concentration is above 11%.
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Electrolytic-tough pitch (ETP) copper, a high-purity copper that contains oxygen as an alloying agent, represents the bulk of electrical conductor applications because of its high electrical conductivity and improved annealability. ETP copper is used for power transmission, power distribution, and telecommunications. Common applications include building wire, motor windings, electrical cables, and busbars. Oxygen-free coppers are used to resist hydrogen embrittlement when extensive amounts of cold work is needed, and for applications requiring higher ductility (e.g.
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This was stabilized at room temperature by alloying it with gallium. Two equal hemispheres of plutonium-gallium alloy were plated with silver, and designated by serial numbers HS-1 and HS-2. The radioactive core generated 15 W of heat, which warmed it up to about , and the silver plating developed blisters that had to be filed down and covered with gold foil; later cores were plated with nickel instead. The Trinity core consisted of just these two hemispheres.
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Many metals react with water to produce , but the rate of hydrogen evolution depends on the metal, the pH, and the presence alloying agents. Most commonly, hydrogen evolution is induced by acids. The alkali and alkaline earth metals, aluminium, zinc, manganese, and iron react readily with aqueous acids. This reaction is the basis of the Kipp's apparatus, which once was used as a laboratory gas source: : Zn + 2 → + In the absence of acid, the evolution of is slower.
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Copper plating and copper sheathing for ships' hulls was widespread; the ships of Christopher Columbus were among the earliest to have this feature. The Norddeutsche Affinerie in Hamburg was the first modern electroplating plant starting its production in 1876. The German scientist Gottfried Osann invented powder metallurgy in 1830 while determining the metal's atomic mass; around then it was discovered that the amount and type of alloying element (e.g., tin) to copper would affect bell tones.
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Most grades of steel are melted once and are then cast or teemed into a solid form prior to extensive forging or rolling to a metallurgically-sound form. In contrast, VIM-VAR steels go through two more highly purifying melts under vacuum. After melting in an electric arc furnace and alloying in an argon oxygen decarburization vessel, steels destined for vacuum remelting are cast into ingot molds. The solidified ingots then head for a vacuum induction melting furnace.
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Antimony forms a highly useful alloy with lead, increasing its hardness and mechanical strength. For most applications involving lead, varying amounts of antimony are used as alloying metal. In lead–acid batteries, this addition improves plate strength and charging characteristics. For sailboats, lead keels are used as counterweights, ranging from 600 lbs to over 8000 lbs; to improve hardness and tensile strength of the lead keel, antimony is mixed with lead between 2% and 5% by volume.
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His design underwent vigorous testing at the National Physical Laboratory, which yielded confirmation of the reliability of the thermometer. Callendar’s platinum thermometer could be used to measure the melting point of metals, allowing it to be used in metal alloying. The apparatus was produced commercially by the Cambridge Instrument Company. The production of modern platinum thermometers were based on Callendar’s model with the accuracy continually improved on, such as more purified platinum and making them smaller.
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Gold and silver belt ornaments were excavated at the same time as the Gold Crown. They were made with a thin band of either gold or silver and had 17 pendants in various shapes. The silver belt ornaments have a similar design as those excavated in Baekje Royal Tomb, indicating contact between Silla and Baekje in the later half of the 5th century. The vessels were made of gold and silver, gold and bronze alloying, and gold and bronze.
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The crystal structure of titanium at ambient temperature and pressure is close-packed hexagonal α phase with a c/a ratio of 1.587. At about 890 °C, the titanium undergoes an allotropic transformation to a body-centred cubic β phase which remains stable to the melting temperature. Some alloying elements, called alpha stabilizers, raise the alpha-to-beta transition temperature, while others (beta stabilizers) lower the transition temperature. Aluminium, gallium, germanium, carbon, oxygen and nitrogen are alpha stabilizers.
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Sensor types which are observing the molten pool are restricted in their applicability range by the fact that molten pool size and arc radiation are dependent on geometrical factors, e.g. material density or composition (alloying constituents). The optical observation of the molten pool region determines changes of the molten pool contour. The deflection from a contour which is defined as “ideal” is interpreted as malposition or as a change of the process behaviour and is compensated subsequently.
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In 2001, Lee Kee established Genesis Alloys (Ningbo) Ltd., the first zinc alloy manufacturing plant in China that utilizes overseas alloying skills and technologies, providing support to Lee Kee's development in Eastern China. In 2006, Lee Kee was successfully listed on the Main Board of the Hong Kong Stock Exchange (stock code: 0637). In 2007, Lee Kee introduced stainless steel in its product range and offered one-stop solution that includes cutting, slitting and shearing services.
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Tin forms several inter-metallic phases with lithium metal, making it a potentially attractive material for battery applications. Large volumetric expansion of tin upon alloying with lithium and instability of the tin-organic electrolyte interface at low electrochemical potentials are the greatest challenges to employment in commercial cells. The problem was partially solved by Sony. Tin inter-metallic compound with cobalt and carbon has been implemented by Sony in its Nexelion cells released in the late 2000s.
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Infrared sensitive semiconductor material is formed by alloying tellurium with cadmium and mercury to form mercury cadmium telluride. Organotellurium compounds such as dimethyl telluride, diethyl telluride, diisopropyl telluride, diallyl telluride and methyl allyl telluride are precursors for synthesizing metalorganic vapor phase epitaxy growth of II-VI compound semiconductors. Diisopropyl telluride (DIPTe) is the preferred precursor for low-temperature growth of CdHgTe by MOVPE. The greatest purity metalorganics of both selenium and tellurium are used in these processes.
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For the steels, the hardness and tensile strength of the steel is related to the amount of carbon present, with increasing carbon levels also leading to lower ductility and toughness. Heat treatment processes such as quenching and tempering can significantly change these properties, however. Cast Iron is defined as an iron–carbon alloy with more than 2.00% but less than 6.67% carbon. Stainless steel is defined as a regular steel alloy with greater than 10% by weight alloying content of Chromium.
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Gallium alloys have been evaluated as substitutes for mercury dental amalgams, but these materials have yet to see wide acceptance. Because gallium wets glass or porcelain, gallium can be used to create brilliant mirrors. When the wetting action of gallium-alloys is not desired (as in Galinstan glass thermometers), the glass must be protected with a transparent layer of gallium(III) oxide. The plutonium used in nuclear weapon pits is stabilized in the δ phase and made machinable by alloying with gallium.
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Mg2BIV (B14=Si, Ge, Sn) compounds and their solid solutions are good thermoelectric materials and their ZT values are comparable with those of established materials. The appropriate production methods are based on direct co-melting, but mechanical alloying has also been used. During synthesis, magnesium losses due to evaporation and segregation of components (especially for Mg2Sn) need to be taken into account. Directed crystallization methods can produce single crystals of Mg2Si, but they intrinsically have n-type conductivity, and doping, e.g.
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Alloyed with gallium arsenide it forms indium gallium arsenide - a material with band gap dependent on In/Ga ratio, a method principally similar to alloying indium nitride with gallium nitride to yield indium gallium nitride. InAs is well known for its high electron mobility and narrow energy bandgap. It is widely used as terahertz radiation source as it is a strong photo-Dember emitter. Quantum dots can be formed in a monolayer of indium arsenide on indium phosphide or gallium arsenide.
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The capital also mentions the genealogy of several Indo-Scythian satraps of Mathura. Rajuvula apparently eliminated the last of the Indo-Greek kings Strato II around 10 CE, and took his capital city, Sagala. The coinage of the period, such as that of Rajuvula, tends to become very crude and barbarized in style. It is also very much debased, the silver content becoming lower and lower, in exchange for a higher proportion of bronze, an alloying technique (billon) suggesting less than wealthy finances.
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Reston, Va.: U.S. Department of the Interior, U.S. Geological Survey. Ceria has also been used as a substitute for its radioactive congener thoria, for example in the manufacture of electrodes used in gas tungsten arc welding, where ceria as an alloying element improves arc stability and ease of starting while decreasing burn-off. Cerium(IV) sulfate is used as an oxidising agent in quantitative analysis. Cerium(IV) in methanesulfonic acid solutions is applied in industrial scale electrosynthesis as a recyclable oxidant.
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An induction furnace uses induction to heat metal to its melting point. Once molten, the high-frequency magnetic field can also be used to stir the hot metal, which is useful in ensuring that alloying additions are fully mixed into the melt. Most induction furnaces consist of a tube of water-cooled copper rings surrounding a container of refractory material. Induction furnaces are used in most modern foundries as a cleaner method of melting metals than a reverberatory furnace or a cupola.
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The difference in strain rates of the inner and outer portion of the part may cause cracks to develop in the outer portion, compelling the use of slower quenching rates to avoid this. By alloying the steel with tungsten, the carbon diffusion is slowed and the transformation to BCT allotrope occurs at lower temperatures, thereby avoiding the cracking. Such a material is said to have its hardenability increased. Tempering following quenching will transform some of the brittle martensite into tempered martensite.
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The raw material for the shop are pure aluminium purchased from smelters, alloying components and aluminium scrap. KUMZ has a number of furnaces: electric, gas, coreless-type induction, electric vacuum holding; and equipment for cutting and scalping. This allows KUMZ to supply its own workshops with high quality wrought aluminium alloy billets, ingots, slabs produced in situ. About 70 aluminium alloys per Russian standards, more than 20 per international standards EN, DIN, ASTM and own Al- Li alloys are mastered.
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904L is an austenitic stainless steel. In comparison to 316L, its molybdenum addition gives it superior resistance to localized attack (pitting and crevice corrosion) by chlorides and greater resistance reducing acids and in particular its copper addition gives it useful corrosion resistance to all concentrations of sulphuric acid. Its high alloying content also gives it greater resistance to chloride stress corrosion cracking, but it is still susceptible. Its low carbon content makes it resistant to sensitization by welding and which prevents intergranular corrosion.
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Bandgap in AgGaO2-ZnO and CdO-ZnO alloys. Similarly to CuGaO2, α-AgGaO2 and α-AgAlO2 have the delafossite crystal structure while the structure of the corresponding β phases is similar to wurtzite (space group Pna2a). β-AgGaO2 is metastable and can be synthesized by ion exchange with a β-NaGaO2 precursor. The bandgaps of β-AgGaO2 and β-AgAlO2 (2.2 and 2.8 eV respectively) are indirect; they fall into the visible range and can be tuned by alloying with ZnO.
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Soft solder filler metals are typically alloys (often containing lead) that have liquidus temperatures below . In this soldering process, heat is applied to the parts to be joined, causing the solder to melt and to bond to the workpieces in a surface alloying process called wetting. In stranded wire, the solder is drawn up into the wire between the strands by capillary action in a process called 'wicking'. Capillary action also takes place when the workpieces are very close together or touching.
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In the U.S., commercial steel production using this method stopped in 1968. It was replaced by processes such as the basic oxygen (Linz–Donawitz) process, which offered better control of final chemistry. The Bessemer process was so fast (10–20 minutes for a heat) that it allowed little time for chemical analysis or adjustment of the alloying elements in the steel. Bessemer converters did not remove phosphorus efficiently from the molten steel; as low-phosphorus ores became more expensive, conversion costs increased.
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In some applications, for example prosthetic devices such as artificial joints, it is desired to have surfaces very resistant to both chemical corrosion and wear due to friction. Ion implantation is used in such cases to engineer the surfaces of such devices for more reliable performance. As in the case of tool steels, the surface modification caused by ion implantation includes both a surface compression which prevents crack propagation and an alloying of the surface to make it more chemically resistant to corrosion.
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Magnesium is brittle, and fractures along shear bands when its thickness is reduced by only 10% by cold rolling (top). However, after alloying Mg with 1% Al and 0.1% Ca, its thickness could be reduced by 54% using the same process (bottom). As of 2013, magnesium alloys consumption was less than one million tonnes per year, compared with 50 million tonnes of aluminum alloys. Their use has been historically limited by the tendency of Mg alloys to corrode, creep at high temperatures, and combust.
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In curve B, the fatigue failure at high stress levels is retarded, and the fatigue limit is eliminated. In curve C, the whole curve is shifted to the left; this indicates a general lowering in fatigue strength, accelerated initiation at higher stresses and elimination of the fatigue limit. To meet the needs of advancing technology, higher-strength materials are developed through heat treatment or alloying. Such high-strength materials generally exhibit higher fatigue limits, and can be used at higher service stress levels even under fatigue loading.
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Alloying metal with lead became a common practice during the period and numerous hoards date to this period. In common with the continental Hallstatt culture, horse harnesses and vehicle fittings were developed and links with the late Urnfield Culture and Hallstatt early C are apparent. Recently, the Ewart Park Phase, and related Atlantic phases, have come to be seen as the probable point of origin of some developments in metalwork, that then spread widely across inland continental Europe. This reverses the previously assumed direction of travel.
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Lead tin telluride, also referred to as PbSnTe or Pb1−xSnxTe, is a ternary alloy of lead, tin and tellurium, generally made by alloying either tin into lead telluride or lead into tin telluride. It is a IV-VI narrow band gap semiconductor material. The band gap of Pb1−xSnxTe is tuned by varying the composition(x) in the material. SnTe can be alloyed with Pb (or PbTe with Sn) in order to tune the band gap from 0.29 eV (PbTe) to 0.18 eV (SnTe).
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Shooting the softest possible shot will result in more shot deformation and a wider pattern. This is often the case with cheap ammunition, as the lead used will have minimal alloying elements such as antimony and be very soft. Spreader wads are wads that have a small plastic or paper insert in the middle of the shot cup, usually a cylinder or "X" cross- section. When the shot exits the barrel, the insert helps to push the shot out from the center, opening up the pattern.
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The equivalent carbon content concept is used on ferrous materials, typically steel and cast iron, to determine various properties of the alloy when more than just carbon is used as an alloyant, which is typical. The idea is to convert the percentage of alloying elements other than carbon to the equivalent carbon percentage, because the iron-carbon phases are better understood than other iron-alloy phases. Most commonly this concept is used in welding, but it is also used when heat treating and casting cast iron.
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Alloy C-264 is a superalloy developed by VDM Metals and launched in 2018. In addition to the alloying element nickel, the alloy contains 25 percent chromium, 20 percent cobalt, about 5.5 percent molybdenum and 1.1 percent aluminum and 1.7 percent titanium. Various tests have shown that the material in the solution-annealed and hardened condition achieves higher hardness values and lower creep rates than, for example, Alloy C-263 (material number 2.4650, UNS N07263). The application temperature is up to 900 degrees Celsius.
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GaAs can be also grown in a semi-insulating form, which is suitable as a lattice-matching insulating substrate for GaAs devices. Conversely, silicon is robust, cheap, and easy to process, whereas GaAs is brittle and expensive, and insulation layers can not be created by just growing an oxide layer; GaAs is therefore used only where silicon is not sufficient.Milton Ohring Reliability and failure of electronic materials and devices Academic Press, 1998, , p. 310. By alloying multiple compounds, some semiconductor materials are tunable, e.g.
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Fine art palladium photographic portrait of Marguerite Agniel by Margaret Watkins, 1925 Prior to 2004, the principal use of palladium in jewelry was the manufacture of white gold. Palladium is one of the three most popular alloying metals in white gold (nickel and silver can also be used). Palladium-gold is more expensive than nickel-gold, but seldom causes allergic reactions (though certain cross- allergies with nickel may occur). When platinum became a strategic resource during World War II, many jewelry bands were made out of palladium.
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High-strength low-alloy steel (HSLA) is a type of alloy steel that provides better mechanical properties or greater resistance to corrosion than carbon steel. HSLA steels vary from other steels in that they are not made to meet a specific chemical composition but rather specific mechanical properties. They have a carbon content between 0.05–0.25% to retain formability and weldability. Other alloying elements include up to 2.0% manganese and small quantities of copper, nickel, niobium, nitrogen, vanadium, chromium, molybdenum, titanium, calcium, rare earth elements, or zirconium.
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They are all good carbide and nitride former , where the precipitates formed can prevent grain growth by pinning grain boundary. They are also all ferrite former, which increase the transition temperature of austenite-ferrite two phase region and reduce the non-recrystallization region . The reduction in non-recrystallization region induces the formation of deformation bands and activated grain boundaries, which are alternative ferrite nucleation site other than grain boundaries . Other alloying elements are mainly for solid solution strengthening including Silicon, Manganese, Chromium, Copper, and Nickel .
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The cell yields a reference EMF of 1.4328 volts at a temperature of 15 °C (288 K). Reference cells must be applied in such a way that no current is drawn from them. The design had two drawbacks--a rather large temperature coefficient of −1.15 mV/°C, and corrosion problems caused by the platinum wires alloying with the zinc amalgam connections where they enter the glass envelope. In 1905, Clark cells were supplanted as a voltage standard by the more temperature-independent Weston cell.
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The two most prevalent shape-memory alloys are copper-aluminium-nickel and nickel-titanium (NiTi), but SMAs can also be created by alloying zinc, copper, gold and iron. Although iron-based and copper-based SMAs, such as Fe-Mn-Si, Cu-Zn-Al and Cu-Al-Ni, are commercially available and cheaper than NiTi, NiTi- based SMAs are preferable for most applications due to their stability and practicability. and superior thermo-mechanic performance. SMAs can exist in two different phases, with three different crystal structures (i.e.
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A titanium cylinder of "grade 2" quality Titanium is used in steel as an alloying element (ferro-titanium) to reduce grain size and as a deoxidizer, and in stainless steel to reduce carbon content. Titanium is often alloyed with aluminium (to refine grain size), vanadium, copper (to harden), iron, manganese, molybdenum, and other metals. Titanium mill products (sheet, plate, bar, wire, forgings, castings) find application in industrial, aerospace, recreational, and emerging markets. Powdered titanium is used in pyrotechnics as a source of bright-burning particles.
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Molten metal is tapped into the ladle from furnaces. After undergoing any ladle treatments, such as alloying and degassing, and arriving at the correct temperature, the ladle is transported to the top of the casting machine. Usually the ladle sits in a slot on a rotating turret at the casting machine. One ladle is in the 'on-cast' position (feeding the casting machine) while the other is made ready in the 'off-cast' position, and is switched to the casting position when the first ladle is empty.
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The metallurgists figured out how to purify the plutonium, and found that heating it to 250° allowed them to work it in the malleable γ phase. It was also found that alloying it with 3 percent gallium would stabilize it in the δ phase. When plutonium at last began to arrive in quantity from the Hanford Site in February 1945, they were ready for production. In a race against the clock, the metallurgists produced plutonium spheres for the Trinity nuclear test by 23 July 1945.
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In pure Ni3Al phase atoms of aluminium are placed at the vertices of the cubic cell and form the sublattice A. Atoms of nickel are located at centers of the faces and form the sublattice B. The phase is not strictly stoichiometric. There may exist an excess of vacancies in one of the sublattices, which leads to deviations from stoichiometry. Sublattices A and B of the γ'-phase can solute a considerable proportion of other elements. The alloying elements are dissolved in the γ-phase as well.
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Bronze, or bronze-like alloys and mixtures, were used for coins over a longer period. Bronze was especially suitable for use in boat and ship fittings prior to the wide employment of stainless steel owing to its combination of toughness and resistance to salt water corrosion. Bronze is still commonly used in ship propellers and submerged bearings. In the 20th century, silicon was introduced as the primary alloying element, creating an alloy with wide application in industry and the major form used in contemporary statuary.
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Osmium–iridium is used for compass bearings and for balances. Their resistance to arc erosion makes iridium alloys ideal for electrical contacts for spark plugs, and iridium-based spark plugs are particularly used in aviation. Pure iridium is extremely brittle, to the point of being hard to weld because the heat-affected zone cracks, but it can be made more ductile by addition of small quantities of titanium and zirconium (0.2% of each apparently works well). Corrosion and heat resistance makes iridium an important alloying agent.
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Crevice corrosion of 316 stainless steel from desalination. SAE 316L grade stainless steel, sometimes referred to as A4 stainless steel or marine grade stainless steel, is the second most common austenitic stainless steel after 304/A2 stainless steel. Its primary alloying constituents after iron, are chromium (between 16–18%), nickel (10–12%) and molybdenum (2–3%), with small (<1%) quantities of silicon, phosphorus & sulfur also present. The addition of molybdenum provides greater corrosion resistance than 304, with respect to localized corrosive attack by chlorides and to general corrosion by reducing acids, such as sulfuric acid.
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The hydrogen content of chromium hydride is between zero and a few hundred parts per million in weight for plain chromium-hydrogen alloys. These values vary depending on alloying elements, such as iron, manganese, vanadium, titanium and so on. Alloys with significantly higher than a few hundred parts per million hydrogen content can be formed, but require extraordinarily high pressures to be stable. Under such conditions, the hydrogen content may contribute up to 0.96% of its weight, at which point it reaches what is called a line compound phase boundary.
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Alloying with lithium reduces structural mass by three effects: ; Displacement : A lithium atom is lighter than an aluminium atom; each lithium atom then displaces one aluminium atom from the crystal lattice while maintaining the lattice structure. Every 1% by mass of lithium added to aluminium reduces the density of the resulting alloy by 3% and increases the stiffness by 5%. This effect works up to the solubility limit of lithium in aluminium, which is 4.2%. ; Strain hardening: Introducing another type of atom into the crystal strains the lattice, which helps block dislocations.
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In Gresham's day, bad money included any coin that had been debased. Debasement was often done by the issuing body, where less than the officially specified amount of precious metal was contained in an issue of coinage, usually by alloying it with a base metal. The public could also debase coins, usually by clipping or scraping off small portions of the precious metal, also known as "stemming" (reeded edges on coins were intended to make clipping evident). Other examples of bad money include counterfeit coins made from base metal.
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Cryomilling is a variation of mechanical milling, in which metallic powders or other samples (e.g. temperature sensitive samples and samples with volatile components) are milled in a cryogen (usually liquid nitrogen or liquid argon) slurry or at a cryogenics temperature under processing parameters, so a nanostructured microstructure is attained. Cryomilling takes advantage of both the cryogenic temperatures and conventional mechanical milling.Suryanarayana C. Mechanical alloying and milling, Progress in Materials Science 46 (2001) 1–184 The extremely low milling temperature suppresses recovery and recrystallization and leads to finer grain structures and more rapid grain refinement.
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In: Studies in the history and archaeology of Jordan V. pp. 523–530. does not necessarily have to be related to two different production centers, but could as well be the result of comparing different groups of objects (i.e., more prestigious weapons of control alloying either with tin or with arsenic) at Tell El Dab’a and similar objects mixed with simpler copper-based ones (like simple daggers, knives, toggle pins, etc.) in Jericho Khalil, L. 1980. The composition and technology of ancient copper alloy artifacts from Jericho and related sites.
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Other elements and inclusions act as hardening agents that prevent the movement of dislocations. The hydrogen in typical iron hydrides may contribute up to 13 ppm in its weight. Varying the amount of hydrogen, as well as controlling its chemical and physical makeup in the final iron hydride (either as a solute element, or as a precipitated phase), hastens the movement of those dislocations that make pure iron ductile, and thus controls and undermines its qualities. Varying the other alloying elements and controlling their chemical and physical makeup also controls, but enhances its qualities.
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But when its concentration exceeds several atomic % , an alloy is formed and the interaction among the added atoms can no longer be neglected. Before giving a more mathematical outline of the RBM it is convenient to give somewhat of a visualization of what happens to a metal upon alloying it. In a pure metal, we'll take silver as an example, all lattice sites are occupied by silver atoms. When different kind of atoms are dissolved into it, for example 10% of copper, some random lattice sites become occupied by copper atoms.
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The archaeologists at Daimabad are not unanimous about the date of the bronzes discovered there. On the basis of the circumstantial evidence, M. N. Deshpande, S. R. Rao and S. A. Sali are of view that these objects belong to the Late Harappan period. Looking at the analysis of the elemental composition of these artifacts, D. P. Agarwal concluded that these objects may belong to the historical period. His conclusion is based on these objects containing more than 1% arsenic, while no arsenical alloying has been found in any other Chalcolithic artifacts.
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The corrosion protection is primarily due to the anodic potential dissolution of zinc versus iron. Zinc acts as a sacrificial anode for protecting iron (steel). While steel is close to -400 mV, depending on alloy composition, electroplated zinc is much more anodic with -980 mV. Steel is preserved from corrosion by cathodic protection. Alloying zinc with cobalt or nickel at levels less than 1% has minimal effect on the potential; but both alloys improve the capacity of the zinc layer to develop a chromate film by conversion coating.
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In the laboratory, platinum wire is used for electrodes; platinum pans and supports are used in thermogravimetric analysis because of the stringent requirements of chemical inertness upon heating to high temperatures (~1000 °C). Platinum is used as an alloying agent for various metal products, including fine wires, noncorrosive laboratory containers, medical instruments, dental prostheses, electrical contacts, and thermocouples. Platinum-cobalt, an alloy of roughly three parts platinum and one part cobalt, is used to make relatively strong permanent magnets. Platinum-based anodes are used in ships, pipelines, and steel piers.
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The West wharf was constructed and commissioned in 2000, and was built to serve the new iron and steel works being constructed by Gunawan Iron and Steel. It was designed to import lump iron ores, sinter, fluxes, coke, and alloying elements for a blast furnace based integrated iron and steel works, the first in South East Asia. It was also built to export the steel plates and slabs to the domestic and international markets. It was to accommodate two large capacity bulk ship unloaders which were bought from Bagnoli, Italy, and shipped to Kemaman.
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In the Middle East, people began alloying copper with zinc to form brass.Buchwald, pp. 39–41 Ancient civilizations took into account the mixture and the various properties it produced, such as hardness, toughness and melting point, under various conditions of temperature and work hardening, developing much of the information contained in modern alloy phase diagrams. For example, arrowheads from the Chinese Qin dynasty (around 200 BC) were often constructed with a hard bronze-head, but a softer bronze-tang, combining the alloys to prevent both dulling and breaking during use.
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Elements high on the periodic table are more likely to be wide bandgap materials. With regard to III-V compounds, nitrides are associated with the largest bandgaps, and, in the II-VI family, oxides are generally considered to be insulators. Bandgaps can often be engineered by alloying, and Vegard's Law states that there is a linear relation between lattice constant and composition of a solid solution at constant temperature. The position of the conduction band minima versus maxima in the band structure determine whether a bandgap is direct or indirect.
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In the 1950s, he constructed a crossed circle wide line NMR spectrometer which could detect deuterium and oxygen-17 isotopes in their natural abundance. Using oxygen-17 as a probe, he demonstrated chemical shifts in organic liquids due to electronic bonding. He subsequently developed an interdisciplinary group which used NMR and susceptibility measurements in metals to show that susceptibility and the hyperfine field at the nucleus were related and could be modified by alloying. The oscillatory nature of the conduction electron polarisation was established in rare earth alloys.
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Nyrstar N.V. is a global multi-metals business, with a market leading position in zinc and lead and growing positions in other base and precious metals, such as copper, gold and silver. Nyrstar has mining and smelting operations located in Europe, North America and Australia. Nyrstar was created in 2007 by combining the zinc smelting and alloying operations of Zinifex (an Australian mining company, now merged with Oxiana Limited to form OZ Minerals) and Umicore (a Belgian materials technology company). It is incorporated in Belgium and has its corporate office in Switzerland.
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The presence of carbides in their matrix plays the dominant role in the qualities of tool steel. The four major alloying elements that form carbides in tool steel are: tungsten, chromium, vanadium and molybdenum. The rate of dissolution of the different carbides into the austenite form of the iron determines the high- temperature performance of steel (slower is better, making for a heat- resistant steel). Proper heat treatment of these steels is important for adequate performance.. The manganese content is often kept low to minimize the possibility of cracking during water quenching.
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The anode material typically consists of a porous (3-6 μm, 45-70% material porosity) Ni based alloy. Ni is alloyed with either Chromium or Aluminum in the 2-10% range. These alloying elements allow for formation of LiCrO2/LiAlO2 at the grain boundaries, which increases the materials' creep resistance and prevents sintering of the anode at the high operating temperatures of the fuel cell. Recent research has looked at using nano Ni and other Ni alloys to increase the performance and decrease the operating temperature of the fuel cell.
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Zirconium is a chemical element with the symbol Zr and atomic number 40. The name zirconium is taken from the name of the mineral zircon (the word is related to Persian zargun (zircon; zar-gun, "gold-like" or "as gold")), the most important source of zirconium. It is a lustrous, grey-white, strong transition metal that closely resembles hafnium and, to a lesser extent, titanium. Zirconium is mainly used as a refractory and opacifier, although small amounts are used as an alloying agent for its strong resistance to corrosion.
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Zamak ingot Zamak (formerly trademarked as ZAMAK and also known as Zamac) is a family of alloys with a base metal of zinc and alloying elements of aluminium, magnesium, and copper. Zamak alloys are part of the zinc aluminum alloy family; they are distinguished from the other ZA alloys because of their constant 4% aluminium composition. The name zamak is an acronym of the German names for the metals of which the alloys are composed: Zink (zinc), Aluminium, Magnesium and Kupfer (copper). The New Jersey Zinc Company developed zamak alloys in 1929.
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In archaeology, the Carp's Tongue complex refers to a tradition of metal working from south eastern England to the later Bronze Age. It is part of the Ewart Park Phase that dates from the ninth century BC. Numerous distinctive metal items have been found in founder's hoards from the Thames valley and Kent that differ from items found elsewhere in Britain. Related items have been found in Ireland and in France. The period was one where experiments in alloying lead with bronze were being used to develop new artefact types some of which have an uncertain purpose.
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In the aerospace industry, Titanium alloys such as Ti–6Al–4V find extensive use in aerospace applications, not only because of their specific high temperature strength, but also because a large number of these alloys exhibit superplastic behavior. Superplastic sheet thermoforming has been identified as a standard processing route for the production of complex shapes, especially and are amenable to superplastic forming (SPF). However, in these alloys the additions of vanadium make them considerably expensive and so, there is a need for developing superplastic titanium alloys with cheaper alloying additions. The Ti-Al-Mn alloy could be such a candidate material.
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The thicker the object is, the more lead was deliberately added to the cast. The highest amounts of lead were measured in the duckbill axes, less in the flat socketed axes, and much less in thinner blades like spears and daggers, which were much more worked and annealed after being cast. This observation corresponds well with the controlled alloying of the duckbill axes and ribbed daggers (with much less lead in the latter) from the MBIIa, but does not correspond with the spears. Although they are derived mainly from MBIIa contexts, their composition is less controlled and more varied.
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Adding pinning points that inhibit the motion of dislocations, such as alloying elements, can introduce stress fields that ultimately strengthen the material by requiring a higher applied stress to overcome the pinning stress and continue dislocation motion. The effects of strain hardening by accumulation of dislocations and the grain structure formed at high strain can be removed by appropriate heat treatment (annealing) which promotes the recovery and subsequent recrystallization of the material. The combined processing techniques of work hardening and annealing allow for control over dislocation density, the degree of dislocation entanglement, and ultimately the yield strength of the material.
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Interactions between defects and alloying elements can cause a redistribution of atoms at sinks such as grain boundaries. The physical effect that can occur is that certain elements will be enriched or depleted in these areas, which often leads to embrittlement of grain boundaries or other detrimental property changes. This is because there is a flux of vacancies towards a sink and a flux of atoms away or toward the sink that may have varying diffusion coefficients. The uneven rates of diffusion cause a concentration of atoms that will not necessarily be in the correct alloy proportions.
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Ion beam mixing is the atomic intermixing and alloying that can occur at the interface separating two different materials during ion irradiation.Ion-solid interactions, Cambridge Solid-State Science series, ch11, p295 It is applied as a process for adhering two multilayers, especially a substrate and deposited surface layer. The process involves bombarding layered samples with doses of ion radiation in order to promote mixing at the interface, and generally serves as a means of preparing electrical junctions, especially between non-equilibrium or metastable alloys and intermetallic compounds. Ion implantation equipment can be used to achieve ion beam mixing.
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The Kemi Mine has approximately 400 employees every day, both employees of Outokumpu and contractors. The purpose of the Kemi Mine in the long production chain from chromite ore to stainless steel is to produce concentrates from ore as raw material for the manufacture of ferrochrome at the ferrochrome plant located in Tornio. The chrome contained in the ferrochrome generated as a product at the ferrochrome plant – used as an alloying material in the steel manufacturing process – is what makes the steel manufactured at the Tornio steel plant stainless. Operational safety, cost-effectiveness and eco-friendliness are characteristics of the Kemi Mine.
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Many steels with high concentrations of these alloying elements behave like precipitation hardening alloys, which produces the opposite effects under the conditions found in quenching and tempering, and are referred to as maraging steels. In carbon steels, tempering alters the size and distribution of carbides in the martensite, forming a microstructure called "tempered martensite". Tempering is also performed on normalized steels and cast irons, to increase ductility, machinability, and impact strength. Steel is usually tempered evenly, called "through tempering," producing a nearly uniform hardness, but it is sometimes heated unevenly, referred to as "differential tempering," producing a variation in hardness.
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Not much pure magnesium is extruded, for it has somewhat poor properties, especially as regards its proof stress. The alloying elements of chief concern at present are aluminium, zinc, cerium and zirconium; manganese is usually also present since, though it has little effect on the strength, it has a valuable function in improving corrosion resistance. One important binary alloy, containing up to 2.0% manganese, is used extensively for the manufacture of rolled sheet. It is comparatively soft and easier to extrude than other alloys, and is also one of the few that can be rolled directly without pre-extrusion.
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A metal that is normally very soft (malleable), such as aluminium, can be altered by alloying it with another soft metal, such as copper. Although both metals are very soft and ductile, the resulting aluminium alloy will have much greater strength. Adding a small amount of non-metallic carbon to iron trades its great ductility for the greater strength of an alloy called steel. Due to its very-high strength, but still substantial toughness, and its ability to be greatly altered by heat treatment, steel is one of the most useful and common alloys in modern use.
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Use of filler metals is required to introduce alloying materials that serve to form oxides that promote the nucleation of acicular ferrite. The HAZ is still a concern that must be addressed with proper preheat and weld procedures to control the cooling rates. Slow cooling rates can be as detrimental and rapid cooling rates in the HAZ. Rapid cooling will form untempered martensite; however, very slow cooling rates caused by high preheat or a combination of preheat and high heat input from the weld procedures can create a very brittle martensite due to high carbon concentrations that form in the HAZ.
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Tin is too soft to be used by itself for architectural purposes so it generally falls into two categories: the alloying of tin with other metals such as copper to form bronze, and the coating of tin on harder metals, such as tinplated iron or steel. Architectural bronzes usually contain about 90% copper and 10% tin, although the content may vary widely. The term “tin ceiling” is a misnomer and early manufacturers did not use the name. However, persons who worked with sheet metal were called tinsmiths, so the term could have sprung from this title.
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The LiMCA methodGuthrie, R. and Doutre, D.A., "On-Line Measurements of Inclusions in Liquid Metals, " Refining and Alloying of Liquid, Aluminum and Ferro Alloys, pp 145-164 (Aug 1985) measures the total concentration and size distribution of inclusions present in aluminum alloys. Its measuring principle is based on an objective and user-independent method. The LiMCA CM system can characterize the cleanliness of a melt at time intervals in the order of one minute. It can therefore monitor, in real-time, the evolution of cleanliness along a cast as a function of process parameters and melt-handling practices.
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Cast iron is a group of iron-carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its colour when fractured: white cast iron has carbide impurities which allow cracks to pass straight through, grey cast iron has graphite flakes which deflect a passing crack and initiate countless new cracks as the material breaks, and ductile cast iron has spherical graphite "nodules" which stop the crack from further progressing. Carbon (C) ranging from 1.8 to 4 wt%, and silicon (Si) 1–3 wt%, are the main alloying elements of cast iron.
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If more than this amount of manganese is added, then manganese carbide forms, which increases hardness and chilling, except in grey iron, where up to 1% of manganese increases strength and density. Nickel is one of the most common alloying elements because it refines the pearlite and graphite structure, improves toughness, and evens out hardness differences between section thicknesses. Chromium is added in small amounts to reduce free graphite, produce chill, and because it is a powerful carbide stabilizer; nickel is often added in conjunction. A small amount of tin can be added as a substitute for 0.5% chromium.
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Iron Age, manufacturer of the hot reversing mill, called this a transition from a curiosity to standard production practice; ovens on both sides of the rolls could better control the steel's temperature. When Crucible removed escape clauses from its employee contracts after the war, the company received approval from the United Steelworkers. During the 1950s, shortages of tungsten and vanadium caused by the wartime drive for cheaper alloying metals resulted in the development of AISI M2 high-speed steel. Colt Industries bought Crucible Steel Corporation of America in 1968, and the Syracuse works become Colt's Crucible Specialty Metals Division.
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The temperature required to forge weld is typically 50 to 90 percent of the melting temperature.Titanium: A Technical Guide, second edition by Matthew J. Donachie -- ASM International 2000 Page 76 Iron can be welded when it surpasses the critical temperature (the A4 temperature) where its allotrope changes from gamma iron (face-centered cubic) to delta iron (body-centered cubic). Since the critical temperatures are affected by alloying agents like carbon, steel welds at a lower temperature-range than iron. As the carbon content in the steel increases, the welding temperature-range decreases in a linear fashion.
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She heads the Surface and Microstructure Engineering research group and within her research activities particular focus is put on the development and characterization of different types of nanocrystalline and sub-microcrystalline materials for functional applications. Different kinds of coatings and energy absorbing materials typically produced by electroplating, thermal spray techniques, and mechanical alloying are studied and optimized with respect to phase formation and distribution, texture, thermal stability, adhesion, etc. However, also superalloys, titanium and advanced steels are investigated with the aim to understand the materials characteristic and to achieve robust and predictable manufacturing processes, lower energy and materials consumption, and reduced environmental impact.
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Kennedy's chemists were able to reduce uranium hydride to uranium-235 metal with 99.96% efficiency, and the metallurgists worked out how to cast and press it into the required shapes. While the chemists worked out how to purify plutonium, the metallurgists had to figure out how to cast it into a solid sphere. Eric Jette's CM-8 (Uranium and Plutonium Metallurgy) group found that they could stabilise plutonium in its malleable δ phase by alloying it with gallium. For his services, he was awarded the Medal for Merit by the President Harry S. Truman in 1946.
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A small fraction of the zircon is converted to the metal, which finds various niche applications. Because of zirconium's excellent resistance to corrosion, it is often used as an alloying agent in materials that are exposed to aggressive environments, such as surgical appliances, light filaments, and watch cases. The high reactivity of zirconium with oxygen at high temperatures is exploited in some specialised applications such as explosive primers and as getters in vacuum tubes. The same property is (probably) the purpose of including Zr nanoparticles as pyrophoric material in explosive weapons such as the BLU-97/B Combined Effects Bomb.
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Secondary alloying elements, which include cobalt, molybdenum and titanium, are added to produce intermetallic precipitates. Original development (by Bieber of Inco in the late 1950s) was carried out on 20 and 25 wt% Ni steels to which small additions of aluminium, titanium, and niobium were made; a rise in the price of cobalt in the late 1970s led to the development of cobalt-free maraging steels. The common, non-stainless grades contain 17–19 wt% nickel, 8–12 wt% cobalt, 3–5 wt% molybdenum and 0.2–1.6 wt% titanium. Addition of chromium produces stainless grades resistant to corrosion.
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Single crystal (SX) superalloys have wide application in the high-pressure turbine section of aero and industrial gas turbine engines due to the unique combination of properties and performance. Since introduction of single crystal casting technology, SX alloy development has focused on increased temperature capability, and major improvements in alloy performance have been associated with the introduction of new alloying elements, including rhenium (Re) and ruthenium (Ru). With increasing turbine entry temperature, it is important to gain a fundamental understanding of the physical phenomena occurring during creep deformation of single crystal superalloys under such extreme condition (i.e. high temperature and high stress).
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For example, whereas in the Neolithic a large chambered cairn or long barrow housed the dead, Early Bronze Age people buried their dead in individual barrows (also commonly known and marked on modern British Ordnance Survey maps as tumuli), or sometimes in cists covered with cairns. The greatest quantities of bronze objects in England were discovered in East Cambridgeshire, where the most important finds were recovered in Isleham (more than 6500 pieces).Hall and Coles, pp. 81–88. Alloying of copper with zinc or tin to make brass or bronze was practiced soon after the discovery of copper itself.
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41xx steel is a family of SAE steel grades, as specified by the Society of Automotive Engineers (SAE). Alloying elements include chromium and molybdenum, and as a result these materials are often informally referred to as chromoly steel (common variant stylings include chrome-moly, cro-moly, CrMo, CRMO, CR- MOLY, and similar). They have an excellent strength to weight ratio and are considerably stronger and harder than standard 1020 steel, but are not easily welded, requiring thermal treatment both before and after welding to avoid cold cracking. While these grades of steel do contain chromium, it is not in great enough quantities to provide the corrosion resistance found in stainless steel.
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U.S. M1917 combat helmet, a variant of Brodie helmet, made from Hadfield steel manganese alloy. Manganese is essential to iron and steel production by virtue of its sulfur- fixing, deoxidizing, and alloying properties, as first recognized by the British metallurgist Robert Forester Mushet (1811–1891) who, in 1856, introduced the element, in the form of Spiegeleisen, into steel for the specific purpose of removing excess dissolved oxygen, sulfur, and phosphorus in order to improve its malleability. Steelmaking, including its ironmaking component, has accounted for most manganese demand, presently in the range of 85% to 90% of the total demand. Manganese is a key component of low-cost stainless steel.
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In particular, when used on a silicon wafer with a < 1 1 1 > crystal orientation, excessive alloying of aluminum (from extended high temperature processing steps) with the underlying silicon can create a short circuit between the diffused FET source or drain areas under the aluminum and across the metallurgical junction into the underlying substrate causing irreparable circuit failures. These shorts are created by pyramidal-shaped spikes of silicon-aluminum alloy pointing vertically "down" into the silicon wafer. The practical high- temperature limit for annealing aluminum on silicon is on the order of 450 °C. Polysilicon is also attractive for the easy manufacturing of self-aligned gates.
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Hydrogen hardens nickel (as it does most metals), inhibiting dislocations in the nickel atom crystal lattice from sliding past one another. Varying the amount of alloying hydrogen and the form of its presence in the nickel hydride (precipitated phase) controls qualities such as the hardness, ductility, and tensile strength of the resulting nickel hydride. Nickel hydride with increased hydrogen content can be made harder and stronger than nickel, but such nickel hydride is also less ductile than nickel. Loss of ductility occurs due to cracks maintaining sharp points due to suppression of elastic deformation by the hydrogen, and voids forming under tension due to decomposition of the hydride.
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Tin and copper are relatively soft metals that will deform on striking (though tin to a lesser extent than copper), but alloying creates a metal which is harder and less ductile and also one with more elasticity than either of the two metals. This metal combination produces a tough, long-wearing material that is resistant to oxidation and subject only to an initial surface weathering. Verdigris forms a protective patina on the surface of bells which coats it against further oxidation. Specifically, it is the combination of low internal damping and low internal sound velocity that makes bell metal specially suitable for resonant percussion instruments.
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In the Middle Bronze (MB) Age (end of 3rd–middle of 2nd millennium BCE) hundreds of metal objects were found. The development of more complex weapons (longer daggers, swords, complex battle axes, etc.) was possible by alloying the copper with arsenic or with tin. All the MBII weapons that were analyzed were made of copper alloyed either with tin (14%–2% Sn) or with arsenic (4.3%–0.5% As), sometimes with a mixture of both usually in low concentrations. These changes in the metal properties of weapons are also reflected in the composition of small objects, like toggle pins that were probably made mainly from re-melting of scrap.Shalev, S. 2002.
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Incoloy refers to a range of superalloys produced by the Special Metals Corporation group of companies. They are mostly nickel-based, and designed for excellent corrosion resistance as well as strength at high temperatures; there are specific alloys for resistance to particular chemical attacks (e.g. alloy 020 is designed to be resistant to sulphuric acid, DS to be used in heat- treating furnaces with reactive atmospheres and many heat cycles) Incoloy MA956 is made by a mechanical alloying rather than a bulk-melting process; it was studied for space reactor components in the JIMO project. It is difficult to weld and needs to be heated to 200C for forming processes.
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Very few metals react to heat treatment in the same manner, or to the same extent, that carbon steel does, and carbon-steel heat-treating behavior can vary radically depending on alloying elements. Steel can be softened to a very malleable state through annealing, or it can be hardened to a state nearly as rigid and brittle as glass by quenching. However, in its hardened state, steel is usually far too brittle, lacking the fracture toughness to be useful for most applications. Tempering is a method used to decrease the hardness, thereby increasing the ductility of the quenched steel, to impart some springiness and malleability to the metal.
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An increase in alloying agents or carbon content causes an increase in retained austenite. Austenite has much higher stacking-fault energy than martensite or pearlite, lowering the wear resistance and increasing the chances of galling, although some or most of the retained austenite can be transformed into martensite by cold and cryogenic treatments prior to tempering. The martensite forms during a diffusionless transformation, in which the transformation occurs due to shear-stresses created in the crystal lattices rather than by chemical changes that occur during precipitation. The shear-stresses create many defects, or "dislocations," between the crystals, providing less-stressful areas for the carbon atoms to relocate.
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Adding cobalt or molybdenum can cause the steel to retain its hardness, even at red-hot temperatures, forming high-speed steels. Often, small amounts of many different elements are added to the steel to give the desired properties, rather than just adding one or two. Most alloying elements (solutes) have the benefit of not only increasing hardness, but also lowering both the martensite start temperature and the temperature at which austenite transforms into ferrite and cementite. During quenching, this allows a slower cooling rate, which allows items with thicker cross-sections to be hardened to greater depths than is possible in plain carbon-steel, producing more uniformity in strength.
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While the high strength of steel results when diffusion and precipitation is prevented (forming martensite), most heat- treatable alloys are precipitation hardening alloys, that depend on the diffusion of alloying elements to achieve their strength. When heated to form a solution and then cooled quickly, these alloys become much softer than normal, during the diffusionless transformation, but then harden as they age. The solutes in these alloys will precipitate over time, forming intermetallic phases, which are difficult to discern from the base metal. Unlike steel, in which the solid solution separates into different crystal phases (carbide and ferrite), precipitation hardening alloys form different phases within the same crystal.
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However, by adding wrought iron or pig iron, allowing it to dissolve into the liquid, the carbon content could be carefully regulated (in a way similar to Asian crucible-steels but without the stark inhomogeneities indicative of those steels). Another benefit was that it allowed other elements to be alloyed with the steel. Huntsman was one of the first to begin experimenting with the addition of alloying agents like manganese to help remove impurities such as oxygen from the steel. His process was later used by many others, such as Robert Hadfield and Robert Forester Mushet, to produce the first alloy steels like mangalloy, high-speed steel, and stainless steel.
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Casting and then machining plutonium is difficult not only because of its toxicity, but because plutonium has many different metallic phases, also known as allotropes. As plutonium cools, changes in phase result in distortion and cracking. This distortion is normally overcome by alloying it with 3–3.5 molar% (0.9–1.0% by weight) gallium, forming a plutonium-gallium alloy, which causes it to take up its delta phase over a wide temperature range."Restricted Data Declassification Decisions from 1946 until Present" When cooling from molten it then suffers only a single phase change, from epsilon to delta, instead of the four changes it would otherwise pass through.
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The post-alloy diffused transistor (PADT), or post-alloy diffused-base transistor, was developed by Philips (but GE and RCA filed for patent and Jacques Pankove of RCA received patent for it) as an improvement to the germanium alloy-junction transistor, it offered even higher speed. It is a type of diffused-base transistor. The Philco micro-alloy diffused transistor had a mechanical weakness that ultimately limited their speed; the thin diffused base layer would break if made too thin, but to get high speed it needed to be as thin as possible. Also it was very hard to control alloying on both sides of such a thin layer.
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Each bit was forged with a hammer, quenched, and then ground with a grindstone. The exact details of the heat treatment and tip geometry were a matter of individual experience and preference. A substantial technological advance occurred in the 1890–1910 period, when Frederick Winslow Taylor applied scientific methods to the study of tool bits and their cutting performance (including their geometry, metallurgy, and heat treatment, and the resulting speeds and feeds, depths of cut, metal-removal rates, and tool life). Along with Maunsel White and various assistants, he developed high speed steels (whose properties come from both their alloying element mixtures and their heat treatment methods).
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Other types of carbonaceous materials besides graphite have been employed as anode material for potassium-ion battery, such as expanded graphite, carbon nanotubes, carbon nanofibers and also nitrogen or phosphorus-doped carbon materials. Conversion anodes which can form compound with potassium ion with boosted storage capacity and reversibility have also been studied to fit for potassium-ion battery. To buffer the volume change of conversion anode, a carbon material matrix is always applied such as MoS2@rGO, Sb2S3-SNG, SnS2-rGO and so on. Classic alloying anodes such as Si, Sb and Sn that can form alloy with lithium ion during cycling process are also applicable for potassium-ion battery.
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Electrolysis of a mixture of beryllium fluoride and sodium fluoride was used to isolate beryllium during the 19th century. The metal's high melting point makes this process more energy-consuming than corresponding processes used for the alkali metals. Early in the 20th century, the production of beryllium by the thermal decomposition of beryllium iodide was investigated following the success of a similar process for the production of zirconium, but this process proved to be uneconomical for volume production. Pure beryllium metal did not become readily available until 1957, even though it had been used as an alloying metal to harden and toughen copper much earlier.
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Iron-carbon phase diagram, showing the conditions under which austenite (γ) is stable in carbon steel. Allotropes of iron; alpha iron and gamma iron Austenite, also known as gamma-phase iron (γ-Fe), is a metallic, non-magnetic allotrope of iron or a solid solution of iron, with an alloying element. In plain-carbon steel, austenite exists above the critical eutectoid temperature of 1000 K (727 °C); other alloys of steel have different eutectoid temperatures. The austenite allotrope is named after Sir William Chandler Roberts-Austen (1843–1902); it exists at room temperature in some stainless steels due to the presence of nickel stabilizing the austenite at lower temperatures.
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The penultimate digit generally identifies the welding positions permissible with the electrode, typically using the values 1 (normally fast-freeze electrodes, implying all position welding) and 2 (normally fast-fill electrodes, implying horizontal welding only). The welding current and type of electrode covering are specified by the last two digits together. When applicable, a suffix is used to denote the alloying element being contributed by the electrode. Common electrodes include the E6010, a fast-freeze, all-position electrode with a minimum tensile strength of which is operated using DCEP, and provides deep weld penetration with a forceful arc capable of burning through light rust or oxides on the workpiece.
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A plaque at Tintern Abbey claims that the well-known brassworks at this site began in 1568.Near this place in the year 1568 Brass was first made by alloying Copper with Zinc. To commemorate the event and on the occasion of the Diamond Jubilee of the National Brassfoundry Association, this plaque was erected in 1957 The plaque also claims though that the brass was made with copper and zinc, which is so unlikely at this date as to make the claimed date also slightly suspect. New brass works were built by Jacob Momma, a German immigrant in 1649 at Esher, probably using Swedish copper.
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The pig-iron was useless as an alloying material—for alloys used in mining equipment—for that reason. Moreover, any very limited market for 'chromic pigs' was not enough to absorb most of the entire production of a relatively large blast furnace. The chrome content of the pigs was far too low to be classed as ferrochrome, an alloy material used to make chromium steel and, in any case, the manufacture of chromium steel (stainless steel) was still in its infancy at the time. Experiments were done in England to see if the chromium could be removed by the process of 'puddling', which is used to make wrought iron.
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Iron is only rarely used for feedthroughs, but frequently gets coated with vitreous enamel, where the interface is also a glass-metal bond. The bond strength is also governed by the character of the oxide layer on its surface. A presence of cobalt in the glass leads to a chemical reaction between the metallic iron and cobalt oxide, yielding iron oxide dissolved in glass and cobalt alloying with the iron and forming dendrites, growing into the glass and improving the bond strength. Iron can not be directly sealed to lead glass, as it reacts with the lead oxide and reduces it to metallic lead.
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However, due to short duration of Bessemer process it allowed little time to adjust composition of the alloying elements in the steel. In particular, phosphorus could not be efficiently removed from molten steel, and widespread use of blowing air instead of oxygen additionally introduced nitrogen into steel. Presence of both of these elements reduced ductility of final product, resulting in material that was not able to withstand frequent compression, extension and torsion loads experienced by these type of vessels during their journeys. As of 2020 the W.H. Gilcher is the second largest unidentified shipwreck on Lake Michigan, only surpassed by the car ferry SS Pere Marquette No. 18.
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This distortion is normally overcome by alloying it with 30–35 mMol (0.9–1.0% by weight) gallium, forming a plutonium-gallium alloy, which causes it to take up its delta phase over a wide temperature range. When cooling from molten it then has only a single phase change, from epsilon to delta, instead of the four changes it would otherwise pass through. Other trivalent metals would also work, but gallium has a small neutron absorption cross section and helps protect the plutonium against corrosion. A drawback is that gallium compounds are corrosive and so if the plutonium is recovered from dismantled weapons for conversion to plutonium dioxide for power reactors, there is the difficulty of removing the gallium.
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O. Samadov has been engaged in studying the influence of external factors on phase transitions of ferroelectric and antiferroelectric and summarizing the achieved results, established the regularities for the first and second phase transitions in spontaneously polarized crystals for the first time. By injecting impurities with various ionic radius to TlİnS2 and TlGaSe2crystals, he has studied their dielectric, pyroelectric, electric properties and influence of γ-rays on these properties. He has shown that when alloying TlİnS2 crystal with Yan-Teylor atoms, the obtained compounds show the properties characteristic for relaxor ferroelectrics. Studying the dielectric and electric relaxation, impedance spectrum, the scientist has observed superionic conductivity in TlGaTe2, TlİnTe2 and TlInSe2crystalsfor the first time.
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Oxygen and carbon can be automatically measured via special probes that dip into the steel, but for all other elements, a "chill" sample — a small, solidified sample of the steel — is analysed on an arc-emission spectrometer. Once the temperature and chemistry are correct, the steel is tapped out into a preheated ladle through tilting the furnace. For plain-carbon steel furnaces, as soon as slag is detected during tapping the furnace is rapidly tilted back towards the deslagging side, minimising slag carryover into the ladle. For some special steel grades, including stainless steel, the slag is poured into the ladle as well, to be treated at the ladle furnace to recover valuable alloying elements.
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Jentz 1995, pp. 47, 82. photos of modified Panthers pp. 150–151 The rear hull top armour was only thick, and had two radiator fans and four air intake louvres over the engine compartment that were vulnerable to strafing by aircraft.Jentz 1995, pp. 55, 108, 147 As the war progressed, Germany was forced to reduce or eliminate critical alloying metals in the production of armour plate, such as nickel, tungsten and molybdenum; this resulted in lower impact resistance levels compared to earlier armour.Spielberger 1993, p. 82 In 1943, Allied bombers struck and severely damaged the Knaben mine in Norway, eliminating a key source of molybdenum; supplies from Finland and Japan were also cut off.
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Puddling in China, circa 1637. Opposite to most alloying processes, liquid pig-iron is poured from a blast furnace into a container and stirred to remove carbon, which diffuses into the air forming carbon dioxide, leaving behind a mild steel to wrought iron. The first known smelting of iron began in Anatolia, around 1800 BC. Called the bloomery process, it produced very soft but ductile wrought iron. By 800 BC, iron-making technology had spread to Europe, arriving in Japan around 700 AD. Pig iron, a very hard but brittle alloy of iron and carbon, was being produced in China as early as 1200 BC, but did not arrive in Europe until the Middle Ages.
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This gave rise to rapid changes in flow velocity and therefore rapid changes of static pressure in areas of high heat transfer. Where resulting vapor bubbles collapsed against a surface, they had the effect of first disrupting protective oxide layers (of cast aluminium materials) and then repeatedly damaging the newly formed surface, preventing the action of some types of corrosion inhibitor (such as silicate based inhibitors). A final problem was the effect that increased material temperature had on the relative electrochemical reactivity of the base metal and its alloying constituents. The result was deep pits that could form and penetrate the engine head in a matter of hours when the engine was running at high load and high speed.
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Normal microstructure of Type 304 stainless steel surface Sensitized metallic microstructure, showing wider intergranular boundaries Stainless steel can pose special corrosion challenges, since its passivating behavior relies on the presence of a major alloying component (chromium, at least 11.5%). Because of the elevated temperatures of welding and heat treatment, chromium carbides can form in the grain boundaries of stainless alloys. This chemical reaction robs the material of chromium in the zone near the grain boundary, making those areas much less resistant to corrosion. This creates a galvanic couple with the well-protected alloy nearby, which leads to "weld decay" (corrosion of the grain boundaries in the heat affected zones) in highly corrosive environments.
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Likewise, the ferromanganese melts and is combined into the pool of liquid iron in the 'well' at the bottom of the cupola. Additions to the molten iron such as ferromanganese, ferrosilicon, silicon carbide and other alloying agents are used to alter the molten iron to conform to the needs of the castings at hand. Pea-sized raw ore of metals such as iron, copper, lead, and even those containing precious metals can be melted in the cupola or blast furnace. Vannoccio Biringuccio describes how to separate metals and slag by pouring the melted ore contents from the furnace into a small pool then peeling off layers of slag or metal from the top as they cool into a solid.
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Calamine brass is brass produced by a particular alloying technique using the zinc ore calamine directly, rather than first refining it to metallic zinc. Direct zinc smelting appears to have been unknown in Europe until the mid-18th century, even though the alloyed calamine brass was in use for centuries, and metallic zinc was produced directly via reducing-atmosphere smelting in India and China from the 12th century CE onwards. Brass is an alloy of copper and zinc and, when it was first developed, methods for producing metallic zinc were unknown. Metallurgists wishing to produce brass thus used calamine (actually a mixture of the virtually indistinguishable zinc ores smithsonite and hemimorphite) as the zinc component of brass.
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After the passing of the Mines Royal Act in 1689, further works were built near Bristol, where brass production became a major industry in the 18th century. Later brass production sites in England included Cheadle and Birmingham. Calamine brass was slowly phased out as zinc smelting techniques were developed in Europe, which produced metallic zinc more suitable for brass production than calamine. However, the conversion away from calamine brass manufacture was slow; a British patent was awarded to William Champion in 1738, but the alloying of metallic zinc and copper to produce brass was not patented until 1781 (by James Emerson), and calamine brass mills persisted in South Wales until as late as 1858.
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Elektron is the registered trademark of a wide range of magnesium alloys manufactured by a British company Magnesium Elektron Limited. There are about 100 alloys in the Elektron range, containing from 0% to 9.5% of some of the following elements in varying proportions: aluminium (< 9.5%), yttrium (5.25%), neodymium (2.7%), silver (2.5%), gadolinium (1.3%), zinc (0.9%), zirconium (0.6%), manganese (0.5%) and other rare-earth metals. Varying amounts of alloying elements (up to 9.5%) added to the magnesium result in changes to mechanical properties such as increased tensile strength, creep resistance, thermal stability or corrosion resistance. Elektron is unusually light and has a specific gravity of about 1.8 compared with the 2.8 of aluminium alloy, or the 7.9 of steel.
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Grounding kits for different diameters Part of a tin-plated ripple Grounding kits / Earthing kits are composed of two main components, a clamp and a cable. The clamp will be screwed on a coaxial cable and in case of lightning strokes in the antenna installation, the voltage will be diverted over a ripple in the clamp with the combined cable and will be earthed / grounded by this way. The clamps of the grounding kits / earthing kits are composed of an ozone- and UV-resistant rubber coat with a device where the ripple can be lodged. The tin-plated ripple with a special alloying enables the bridging over big tolerances between kit and coaxial cable which is important for a best possible voltage transmission.
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7075 aluminium alloy (AA7075) is an aluminium alloy, with zinc as the primary alloying element. It has excellent mechanical properties, and exhibits good ductility, high strength, toughness and good resistance to fatigue. It is more susceptible to embrittlement than many other aluminium alloys because of microsegregation, but has significantly better corrosion resistance than the 2000 alloys. It is one of the most commonly used aluminium alloy for highly stressed structural applications, and has been extensively utilized in aircraft structural parts.ASM Handbook Volume 2: Properties and Selection: Nonferrous Alloys and Special-Purpose Materials, 1990 p. 137-38 7075 aluminium alloy's composition roughly includes 5.6–6.1% zinc, 2.1–2.5% magnesium, 1.2–1.6% copper, and less than a half percent of silicon, iron, manganese, titanium, chromium, and other metals.
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Precipitation strengthening is possible if the line of solid solubility slopes strongly toward the centre of a phase diagram. While a large volume of precipitate particles is desirable, a small enough amount of the alloying element should be added that it remains easily soluble at some reasonable annealing temperature. Elements used for precipitation strengthening in typical aluminium and titanium alloys make up about 10% of their composition. While binary alloys are more easily understood as an academic exercise, commercial alloys often use three components for precipitation strengthening, in compositions such as Al(Mg, Cu) and Ti(Al, V). A large number of other constituents may be unintentional, but benign, or may be added for other purposes such as grain refinement or corrosion resistance.
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In the body-centred cubic arrangement, there is an iron atom in the centre of each cube, and in the face-centred cubic, there is one at the center of each of the six faces of the cube. It is the interaction of the allotropes of iron with the alloying elements that gives iron-hydrogen alloy its range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In iron hydride, small amounts of hydrogen within the iron act as a softening agent that promote the movement of dislocations that are common in the crystal lattices of iron atoms.
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Cassiterite and quartz crystals Tin extraction and use can be dated to the beginning of the Bronze Age around 3000 BC, during which copper objects formed from polymetallic ores had different physical properties . The earliest bronze objects had tin or arsenic content of less than 2% and are therefore believed to be the result of unintentional alloying due to trace metal content in copper ores such as tennantite, which contains arsenic . The addition of a second metal to copper increases its hardness, lowers the melting temperature, and improves the casting process by producing a more fluid melt that cools to a denser, less spongy metal . This was an important innovation that allowed for the much more complex shapes cast in closed molds of the Bronze Age.
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The archaeological record in Egypt, Peru and the Caucasus suggests that arsenical bronze was produced for a time alongside tin bronze. At Tepe Yahya its use continued into the Iron Age for the manufacture of trinkets and decorative objects, thus demonstrating that there was not a simple succession of alloys over time, with superior new alloys replacing older ones. There are few real advantages metallurgically for the superiority of tin bronze, and early authors suggested that arsenical bronze was phased out due to its health effects. It is more likely that it was phased out in general use because alloying with tin gave castings which had similar strength to arsenical bronze but did not require further work- hardening to achieve useful strength.
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This term is often used in the field of metallurgy to refer to the extent that an alloying element will dissolve into the base metal without forming a separate phase. The solvus or solubility line (or curve) is the line (or lines) on a phase diagram that give the limits of solute addition. That is, the lines show the maximum amount of a component that can be added to another component and still be in solid solution. In the solid's crystalline structure, the 'solute' element can either take the place of the matrix within the lattice (a substitutional position; for example, chromium in iron) or take a place in a space between the lattice points (an interstitial position; for example, carbon in iron).
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Martensite is formed in carbon steels by the rapid cooling (quenching) of the austenite form of iron at such a high rate that carbon atoms do not have time to diffuse out of the crystal structure in large enough quantities to form cementite (Fe3C). Austenite is gamma-phase iron (γ-Fe), a solid solution of iron and alloying elements. As a result of the quenching, the face-centered cubic austenite transforms to a highly strained body- centered tetragonal form called martensite that is supersaturated with carbon. The shear deformations that result produce a large number of dislocations, which is a primary strengthening mechanism of steels. The highest hardness of a pearlitic steel is 400 Brinell, whereas martensite can achieve 700 Brinell.
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Intergranular corrosion is generally considered to be caused by the segregation of impurities at the grain boundaries or by enrichment or depletion of one of the alloying elements in the grain boundary areas. Thus in certain aluminium alloys, small amounts of iron have been shown to segregate in the grain boundaries and cause intergranular corrosion. Also, it has been shown that the zinc content of a brass is higher at the grain boundaries and subject to such corrosion. High-strength aluminium alloys such as the Duralumin-type alloys (Al-Cu) which depend upon precipitated phases for strengthening are susceptible to intergranular corrosion following sensitization at temperatures of about 120 °C. Nickel-rich alloys such as Inconel 600 and Incoloy 800 show similar susceptibility.
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The proportions of this mixture suggests that the candlestick was made from a hoard of old coins. The Benin Bronzes are in fact brass, and the Romanesque Baptismal font at St Bartholomew's Church, Liège is described as both bronze and brass. In the Bronze Age, two forms of bronze were commonly used: "classic bronze", about 10% tin, was used in casting; and "mild bronze", about 6% tin, was hammered from ingots to make sheets. Bladed weapons were mostly cast from classic bronze, while helmets and armor were hammered from mild bronze. Commercial bronze (90% copper and 10% zinc) and architectural bronze (57% copper, 3% lead, 40% zinc) are more properly regarded as brass alloys because they contain zinc as the main alloying ingredient.
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The first way to overcome this challenge is by using a seed material, which is properly oriented and that nucleates new lamellae during processing with the same orientation as the original material . It is placed in front of the main bulk of material so that when the melt is solidifying it has a precedent for the correct orientation to follow . If a seed is not used, the other method of achieving the high strength single lamellar phase is to have the lamellar structure oriented along the growth direction . However, this is only successful for a small window of the solidification, as its success from the columnar growth of the beta phase followed by the equiaxed growth of the alpha phase and alloying with boron is compromised by the high thermal gradient of the cooling .
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Extractive metallurgy is a branch of metallurgical engineering wherein process and methods of extraction of metals from their natural mineral deposits are studied. The field is a materials science, covering all aspects of the types of ore, washing, concentration, separation, chemical processes and extraction of pure metal and their alloying to suit various applications, sometimes for direct use as a finished product, but more often in a form that requires further working to achieve the given properties to suit the applications.Brent Hiskey "Metallurgy, Survey" in Kirk-Othmer Encyclopedia of Chemical Technology, 2000, Wiley-VCH, Weinheim. The field of ferrous and non-ferrous extractive metallurgy have specialties that are generically grouped into the categories of mineral processing, hydrometallurgy, pyrometallurgy, and electrometallurgy based on the process adopted to extract the metal.
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The process of mechanical alloying involves the production of a composite powder particles by: # Using a high energy mill to favor plastic deformation required for cold welding and reduce the process times # Using a mixture of elemental and master alloy powders (the latter to reduce the activity of the element, since it is known that the activity in an alloy or a compound could be orders of magnitude less than in a pure metal) # Eliminating the use of surface-active agents which would produce fine pyrophoric powder as well as contaminate the powder # Relying on a constant interplay between welding and fracturing to yield a powder with a refined internal structure, typical of very fine powders normally produced, but having an overall particle size which was relatively coarse, and therefore stable. Narrow particle size distribution.
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The appearance of gold or silver seems to have been important, with a high number of gilded or silvered objects as well as the appearance of Tumbaga, a alloy of copper and gold, and sometimes also silver. Arsenic bronze was also smelted from sulphidic ores, a practice either independently developed or learned from the southern tradition. The earliest known powder metallurgy, and earliest working of platinum in the world, was apparently developed by the cultures of Esmeraldas (NW Ecuador) before the Spanish Conquest Beginning with the La Tolita culture (600 bc - 200 ad), Ecuadorian cultures mastered the soldering of platinum grains through alloying with copper, gold and silver, producing platinum-surfaced rings, handles, ornaments and utensils. This technology was eventually noticed and adopted by the Spanish c.1730.
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However, in some regimes no M3C species are observed indicating a direct transfer of metal atoms into the graphite layer.On the Mechanism of Metal Dusting Corrosion (no date) C.M. Chun, J.D. Mumford and T.A. Ramanarayanan The temperatures normally associated with metal dusting are high (300–850 °C). From a general understanding of chemistry, it can be deduced that at lower temperatures, the rate of reaction to form the metastable M3C species is too low to be significant, and at much higher temperatures the graphite layer is unstable and so CO deposition does not occur (at least to any appreciable degree). Very briefly, there are several proposed methods for prevention or reduction of metal dusting; the most common seem to be aluminide coatings, alloying with copper and addition of steam.
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Harappan civilization, one of the earliest civilizations of the Bronze Age The Bronze Age is a historical period that was characterized by the use of bronze, in some areas proto-writing, and other early features of urban civilization. The Bronze Age is the second principal period of the three-age Stone-Bronze-Iron system, as proposed in modern times by Christian Jürgensen Thomsen, for classifying and studying ancient societies. An ancient civilization is defined to be in the Bronze Age either by producing bronze by smelting its own copper and alloying with tin, arsenic, or other metals, or by trading for bronze from production areas elsewhere. Bronze itself is harder and more durable than other metals available at the time, allowing Bronze Age civilizations to gain a technological advantage.
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There are four transition temperatures associated to the austenite-to-martensite and martensite-to-austenite transformations. Starting from full austenite, martensite begins to form as the alloy is cooled to the so-called martensite start temperature, or Ms, and the temperature at which the transformation is complete is called the martensite finish temperature, or Mf. When the alloy is fully martensite and is subjected to heating, austenite starts to form at the austenite start temperature, As, and finishes at the austenite finish temperature, Af. Thermal hysteresis of nitinol's phase transformationThe cooling/heating cycle shows thermal hysteresis. The hysteresis width depends on the precise nitinol composition and processing. Its typical value is a temperature range spanning about 20-50 K (20-50 °C; 36-90 °F) but it can be reduced or amplified by alloying and processing.
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Calcium compounds are widely used in many industries: in foods and pharmaceuticals for calcium supplementation, in the paper industry as bleaches, as components in cement and electrical insulators, and in the manufacture of soaps. On the other hand, the metal in pure form has few applications due to its high reactivity; still, in small quantities it is often used as an alloying component in steelmaking, and sometimes, as a calcium–lead alloy, in making automotive batteries. Calcium is the most abundant metal and the fifth-most abundant element in the human body. As electrolytes, calcium ions play a vital role in the physiological and biochemical processes of organisms and cells: in signal transduction pathways where they act as a second messenger; in neurotransmitter release from neurons; in contraction of all muscle cell types; as cofactors in many enzymes; and in fertilization.
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N. Dobrokhotov develops basic theory and practice of deoxidation and alloying of finished steel in ladle with solid ferroalloys, use of which radically improved steelmaking process. It was first tested at the Volgograd metallurgical plant "Red October", and later - at the Izhevsk metallurgical plant in the name of 50 years of the USSR, at Kuznetsk metallurgical plant in the name of Lenin and at other plants. Implementing of it made it possible to increase the productivity of smelting furnaces, reduce haze of alloy additions and deoxidants, reduce the cost of steel and improve the quality of the material. N. Dobrokhotov developed a scientific basis for steel pouring at high temperatures to improve the quality, that gave rise to a new direction in the field of steel pouring to ingots and obtaining shaped steel casts, thereby improving their quality at all indicators.
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Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use. Bronze artifacts from Sumerian cities and Egyptian artifacts of copper and bronze alloys date to 3000 BC. The Bronze Age began in Southeastern Europe around 3700 - 3300 BC, in Northwestern Europe about 2500 BC. It ended with the beginning of the Iron Age, 2000-1000 BC in the Near East, 600 BC in Northern Europe. The transition between the Neolithic period and the Bronze Age was formerly termed the Chalcolithic period (copper-stone), with copper tools being used with stone tools. This term has gradually fallen out of favor because in some parts of the world the Calcholithic and Neolithic are coterminous at both ends.
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Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use. Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloys date to 3000 BC. The Bronze Age began in Southeastern Europe around 3700–3300 BC, in Northwestern Europe about 2500 BC. It ended with the beginning of the Iron Age, 2000–1000 BC in the Near East, and 600 BC in Northern Europe. The transition between the Neolithic period and the Bronze Age was formerly termed the Chalcolithic period (copper-stone), when copper tools were used with stone tools. The term has gradually fallen out of favor because in some parts of the world, the Chalcolithic and Neolithic are coterminous at both ends.
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Ceremonial giant bronze dirk of the Plougrescant-Ommerschans type, Plougrescant, France, 1500–1300 BC. Tin extraction and use can be dated to the beginnings of the Bronze Age around 3000 BC, when it was observed that copper objects formed of polymetallic ores with different metal contents had different physical properties. The earliest bronze objects had a tin or arsenic content of less than 2% and are therefore believed to be the result of unintentional alloying due to trace metal content in the copper ore. The addition of a second metal to copper increases its hardness, lowers the melting temperature, and improves the casting process by producing a more fluid melt that cools to a denser, less spongy metal. This was an important innovation that allowed for the much more complex shapes cast in closed molds of the Bronze Age.
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Zinc deposits have been exploited for thousands of years, with the oldest zinc mine, located in Rajasthan, India established nearly 2000 years BP. Pure zinc production occurred in the 9th century AD while, earlier in antiquity zinc was primarily utilized in the alloying of copper to produce Brass. This is because the isolation of zinc metal from its ore poses a unique challenge. This is because at the temperature zinc is released from its ore it vaporizes into a gas, and if the furnace is not air tight, the gaseous zinc reacts with the air to form zinc oxide. Metallic zinc smelting occurred in 9th century BC in India, followed soon by China 300 years later, and In Europe by 1738 AD. The methods of smelting in China and India were most likely independently developed, while the method of smelting developed in Europe was likely derived by the Indian method.
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Because the other platinum-family members were not discovered yet (platinum was the first in the list), Scheffer and Sickingen made the false assumption that due to its hardness—which is slightly more than for pure iron—platinum would be a relatively non-pliable material, even brittle at times, when in fact its ductility and malleability are close to that of gold. Their assumptions could not be avoided because the platinum they experimented with was highly contaminated with minute amounts of platinum-family elements such as osmium and iridium, amongst others, which embrittled the platinum alloy. Alloying this impure platinum residue called "plyoxen" with gold was the only solution at the time to obtain a pliable compound, but nowadays, very pure platinum is available and extremely long wires can be drawn from pure platinum, very easily, due to its crystalline structure, which is similar to that of many soft metals.Platinum . mysite.du.
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Initially, bronze was made out of copper and arsenic, forming arsenic bronze, or from naturally or artificially mixed ores of copper and arsenic, with the earliest artifacts so far known coming from the Iranian plateau in the 5th millennium BC. It was only later that tin was used, becoming the major non-copper ingredient of bronze in the late 3rd millennium BC. Tin bronze was superior to arsenic bronze in that the alloying process could be more easily controlled, and the resulting alloy was stronger and easier to cast. Also, unlike arsenic, metallic tin and fumes from tin refining are not toxic. The earliest tin-alloy bronze dates to 4500 BC in a Vinča culture site in Pločnik (Serbia). Other early examples date to the late 4th millennium BC in Egypt,History of Africa#Metallurgy Susa (Iran) and some ancient sites in China, Luristan (Iran) and Mesopotamia (Iraq).
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Though the outward appearance of the engine is the same as before, new quality control techniques employ better alloying and casting, better engineering tolerances, and better paint, powder coating and stainless steel exhausts while retaining the advantage of continuity with the inherently balanced design of a horizontally-opposed flat twin engine with roller bearings in a solid frame. The motorcycles are mainly exported to Australia, the UK, France, Netherlands, Belgium, Spain, Greece, Norway, Finland, Iceland, Sweden, Germany, Egypt, Iran, South Africa, Brazil, Uruguay, Paraguay, and the US. The number sold since the factory was founded exceeds 3.2 million. IMZ-Ural is the only Russian manufacturer of large capacity motorcycles and one of few manufacturers of sidecar motorcycles in the world. Like most motorcycle manufacturers, Ural now sources pre-made components in many cases -- buying alternators from Nippon Denso, brakes from Brembo, handlebar controls from Domino, forks from Paioli, ignitions from Ducati Energia, etc.
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The alt=A colossal statue of a robed female figure who bears a torch in her raised left hand and a tablet in her other hand The strength or durability of heavy metals such as chromium, iron, nickel, copper, zinc, molybdenum, tin, tungsten, and lead, as well as their alloys, makes them useful for the manufacture of artefacts such as tools, machinery, appliances, utensils, pipes, railroad tracks, buildings and bridges, automobiles, locks,: "Here is a rugged hard metal cutter ... for cutting ... through ... padlocks, steel grilles and other heavy metals." furniture, ships, planes, coinage and jewellery. They are also used as alloying additives for enhancing the properties of other metals. Of the two dozen elements that have been used in the world's monetised coinage only two, carbon and aluminium, are not heavy metals. Gold, silver, and platinum are used in jewellery as are (for example) nickel, copper, indium, and cobalt in coloured gold.
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Various accessories for SMAW The choice of electrode for SMAW depends on a number of factors, including the weld material, welding position and the desired weld properties. The electrode is coated in a metal mixture called flux, which gives off gases as it decomposes to prevent weld contamination, introduces deoxidizers to purify the weld, causes weld-protecting slag to form, improves the arc stability, and provides alloying elements to improve the weld quality. Electrodes can be divided into three groups—those designed to melt quickly are called "fast- fill" electrodes, those designed to solidify quickly are called "fast-freeze" electrodes, and intermediate electrodes go by the name "fill-freeze" or "fast- follow" electrodes. Fast-fill electrodes are designed to melt quickly so that the welding speed can be maximized, while fast-freeze electrodes supply filler metal that solidifies quickly, making welding in a variety of positions possible by preventing the weld pool from shifting significantly before solidifying.
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The use of steels in superalloy applications is of interest because certain steel alloys have showed creep and oxidation resistance similar to that of Ni-based superalloys, while being far less expensive to produce. Gamma (γ): Like the phases found in Ni-based superalloys, Fe-based alloys feature a matrix phase of austenite iron (FCC). Alloying elements that are commonly found in these stainless steel alloys include: Al, B, C, Co, Cr, Mo, Ni, Nb, Si, Ti, W, and Y. While Al is introduced for its oxidation benefits, Al additions must be kept at low weight fractions (wt.%) because Al stabilizes a ferritic (BCC) primary phase matrix, which is an undesirable phase in superalloy microstructures, as it is inferior to the high temperature strength exhibited by an austenitic (FCC) primary phase matrix. Gamma-prime (γ’): This phase is introduced as precipitates to strengthen the alloy. Like in Ni-based alloys, γ’-Ni3Al precipitates can be introduced with the proper balance of Al, Ni, Nb, and Ti additions.
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The first coinage which was extensively used in southern Tibet was silver coins, which were supplied by the Nepalese Malla Kingdoms and the first kings of the subsequent Shah dynasty from about 1640 until 1791.Rhodes, Nicholas G., Gabrisch, Karl & Valdettaro, Carlo (1989) The Coinage of Nepal from the earliest times until 1911, Royal Numismatic Society, Special Publication, No. 21, London Tibet provided the silver for the striking of these coins and received coins at the same weight, the Nepalese reaping a handsome profit by alloying the pure silver with copper before the striking of the coins. Owing to a dispute between Nepal and Tibet regarding the fineness of the silver coins supplied by Nepal, the export of these coins was disrupted after the mid-eighteenth century.Martynov, A. S.: O pervych chekankakh monety v Tibete Kratkie Soobshcheniia Akademia Nauk SSSR, Institut Narodoz Azji, No. 69, Moscow, pp. 197–202Martynov, A.S. (July/Sept 1987) Some Aspects of the Qing Policy in Tibet at the Close of the 18th Century.
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It has been recently shown that cold wire drawing not only strengthens pearlite by refining the lamellae structure, but also simultaneously causes partial chemical decomposition of cementite, associated with an increased carbon content of the ferrite phase, deformation induced lattice defects in ferrite lamellae, and even a structural transition from crystalline to amorphous cementite. The deformation-induced decomposition and microstructural change of cementite is closely related to several other phenomena such as a strong redistribution of carbon and other alloy elements like silicon and manganese in both the cementite and the ferrite phase; a variation of the deformation accommodation at the phase interfaces due to a change in the carbon concentration gradient at the interfaces; and mechanical alloying.. Pearlite was first identified by Henry Clifton Sorby and initially named sorbite, however the similarity of microstructure to nacre and especially the optical effect caused by the scale of the structure made the alternative name more popular. Bainite is a similar structure with lamellae much smaller than the wavelength of visible light and thus lacks this pearlescent appearance. It is prepared by more rapid cooling.
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Tantalum carbide is widely used as sintering additive in ultra-high temperature ceramics (UHTCs) or as a ceramic reinforcement in high- entropy alloys (HEAs) due to its excellent physical properties in melting point, hardness, elastic modulus, thermal conductivity, thermal shock resistance, and chemical stability, which makes it a desirable material for aircraft and rockets in aerospace industries. Wang et al. have synthesized SiBCN ceramic matrix with TaC addition by mechanical alloying plus reactive hot-pressing sintering methods, in which BN, graphite and TaC powders were mixed with ball-milling and sintered at 1900 °C to obtain SiBCN-TaC composites. For the synthesis, the ball-milling process refined the TaC powders down to 5 nm without reacting with other components, allowing to form agglomerates that are composed of spherical clusters with a diameter of 100nm-200nm. TEM analysis showed that TaC is distributed either randomly in the form of nanoparticles with sizes of 10-20nm within the matrix or distributed in BN with smaller size of 3-5nm. As a result, the composite with 10 wt% addition of TaC improved the fracture toughness of the matrix, reaching 399.5MPa compared to 127.9MPa of pristine SiBCN ceramics.
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5 has an amphoteric oxide; and can form anionic aluminates. Aluminium forms Zintl phases such as LiAl, Ca3Al2Sb6, and SrAl2.Kauzlarich 2005, pp. 6009–10 A thin protective layer of oxide confers a reasonable degree of corrosion resistance.Dennis & Such 1993, p. 391 It is susceptible to attack in low pH (<4) and high (> 8.5) pH conditions,Cramer & Covino 2006, p. 25 a phenomenon that is generally more pronounced in the case of commercial purity aluminium and aluminium alloys.Russell & Lee 2005, p. 360 Given many of these properties and its proximity to the dividing line between metals and nonmetals, aluminium is occasionally classified as a metalloid. Despite its shortcomings, it has a good strength-to-weight ratio and excellent ductility; its mechanical strength can be improved considerably with the use of alloying additives; its very high thermal conductivity can be put to good use in heat sinks and heat exchangers;Clegg & Dovaston 2003, p. 5/5 and it has a high electrical conductivity. At lower temperatures, aluminium increases its deformation strength (as do most materials) whilst maintaining ductility (as do face-centred cubic metals generally).Kent 1993, pp. 13–14 Chemically, bulk aluminium is a strongly electropositive metal, with a high negative electrode potential.
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