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Aluminium–copper Alloys
Aluminium–copper alloys (AlCu) are Aluminium alloy, aluminium alloys that consist largely of aluminium (Al) and traces of copper (Cu) as the main Alloy, alloying elements. Important grades also contain additives of magnesium, iron, nickel and silicon (AlCu(Mg, Fe, Ni, Si)), often manganese is also included to increase strength (see aluminium–manganese alloys). The main area of application is aircraft construction. The alloys have medium to high strength and can be Precipitation hardening, age hardened. They are both . Also available as cast alloy. Their susceptibility to corrosion and their poor weldability are disadvantageous. Duralumin is the oldest variety in this group and goes back to Alfred Wilm, who discovered it in 1903. Aluminium could only be used as a widespread construction material thanks to the aluminium–copper alloys, as pure aluminium is much too soft for this and other hardenable alloys such as aluminium–magnesium–silicon alloys (AlMgSi) or the naturally h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium Alloy
An aluminium alloy ( UK/IUPAC) or aluminum alloy ( NA; see spelling differences) is an alloy in which aluminium (Al) is the predominant metal. The typical alloying elements are copper, magnesium, manganese, silicon, tin, nickel and zinc. There are two principal classifications, namely casting alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost-effective products due to their low melting points, although they generally have lower tensile strengths than wrought alloys. The most important cast aluminium alloy system is Al–Si, where the high levels of silicon (4–13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.I. J. Polmear, ''Light Alloys'', A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cubic Crystal System
In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals. There are three main varieties of these crystals: *Primitive cubic (abbreviated ''cP'' and alternatively called simple cubic) *Body-centered cubic (abbreviated ''cI'' or bcc) *Face-centered cubic (abbreviated ''cF'' or fcc) Note: the term fcc is often used in synonym for the ''cubic close-packed'' or ccp structure occurring in metals. However, fcc stands for a face-centered cubic Bravais lattice, which is not necessarily close-packed when a motif is set onto the lattice points. E.g. the diamond and the zincblende lattices are fcc but not close-packed. Each is subdivided into other variants listed below. Although the ''unit cells'' in these crystals are conventionally taken to be cubes, the primitive unit cells often are not. Bravais lattices The three Bravais latices ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intermetallic
An intermetallic (also called intermetallic compound, intermetallic alloy, ordered intermetallic alloy, long-range-ordered alloy) is a type of metallic alloy that forms an ordered solid-state compound between two or more metallic elements. Intermetallics are generally hard and brittle, with good high-temperature mechanical properties. They can be classified as stoichiometric or nonstoichiometic. The term "intermetallic compounds" applied to solid phases has long been in use. However, Hume-Rothery argued that it misleads, suggesting a fixed stoichiometry and a clear decomposition into species. Definitions Research definition In 1967 defined intermetallic compounds as ''solid phases containing two or more metallic elements, with optionally one or more non-metallic elements, whose crystal structure differs from that of the other constituents''. This definition includes: * Electron (or Hume-Rothery) compounds * Size packing phases. e.g. Laves phases, Frank–Kasper phases and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mass Percent
In chemistry, the mass fraction of a substance within a mixture is the ratio w_i (alternatively denoted Y_i) of the mass m_i of that substance to the total mass m_\text of the mixture. Expressed as a formula, the mass fraction is: : w_i = \frac . Because the individual masses of the ingredients of a mixture sum to m_\text, their mass fractions sum to unity: : \sum_^ w_i = 1. Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called ''percentage by weight'', abbreviated ''wt.%'' or ''% w/w''; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size; mole fraction (percentage by moles, mol%) and volume fraction ( percentage by volume, vol%) are others. When the prevalences of interest are those of individual chemical elements, rather than of compounds or other substances, the term ''mass fraction'' can also refer to the ratio of the mass of an element to the total ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutectic System
A eutectic system or eutectic mixture ( ) is a type of a homogeneous mixture that has a melting point lower than those of the constituents. The lowest possible melting point over all of the mixing ratios of the constituents is called the ''eutectic temperature''. On a phase diagram, the eutectic temperature is seen as the eutectic point (see plot on the right). Non-eutectic mixture ratios have different melting temperatures for their different constituents, since one component's lattice will melt at a lower temperature than the other's. Conversely, as a non-eutectic mixture cools down, each of its components solidifies into a lattice at a different temperature, until the entire mass is solid. A non-eutectic mixture thus does not have a single melting/freezing point temperature at which it changes phase, but rather a temperature at which it changes between liquid and slush (known as the liquidus) and a lower temperature at which it changes between slush and solid (the solidu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum Association
The Aluminum Association is a trade association for the aluminum production, fabrication and recycling industries, and their suppliers. The Association is a 501(c)(6) non-profit organization based in Arlington, Virginia, United States. (The Association was based in Washington, D.C. until .) Pursuant to seven ANSI H35 standards, The Aluminum Association registers and publishes specifications describing the composition, mechanical properties and nomenclature of aluminum alloys in the United States. These alloys are identified by the abbreviation "AA", for example AA 6061-T6. Before world war II In 1933, Congress passed the National Industrial Recovery Act (NIRA), a New Deal measure requesting each industry to establish codes and guidelines of fair competition. Representatives of 13 aluminum companies met in Pittsburgh, Pennsylvania to set up these codes and formed the Association of Manufacturers in the Aluminum Industry. Members of the Association included the Aluminum Company o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Science
Popular science (also called pop-science or popsci) is an interpretation of science intended for a general audience. While science journalism focuses on recent scientific developments, popular science is more broad ranging. It may be written by professional science journalists or by scientists themselves. It is presented in many forms, including books, film and television documentaries, magazine articles, and web pages. History Before the modern specialization and professionalization of science, there was often little distinction between "science" and "popular science", and works intended to share scientific knowledge with a general reader existed as far back as Greek and Roman antiquity. Without these popular works, much of the scientific knowledge of the era might have been lost. For example, none of the original works of the Greek astronomer Eudoxus (4th century BC) have survived, but his contributions were largely preserved due to the didactic poem '' Phenomena'' writte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quenching
In materials science, quenching is the rapid cooling of a workpiece in water, gas, oil, polymer, air, or other fluids to obtain certain material properties. A type of heat treating, quenching prevents undesired low-temperature processes, such as phase transformations, from occurring. It does this by reducing the window of time during which these undesired reactions are both thermodynamically favorable and kinetically accessible; for instance, quenching can reduce the crystal grain size of both metallic and plastic materials, increasing their hardness. In metallurgy, quenching is most commonly used to harden steel by inducing a martensite transformation, where the steel must be rapidly cooled through its eutectoid point, the temperature at which austenite becomes unstable. Rapid cooling prevents the formation of cementite structure, instead forcibly dissolving carbon atoms in the ferrite lattice. In steel alloyed with metals such as nickel and manganese, the eutectoid t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aktiengesellschaft
(; abbreviated AG ) is a German language, German word for a corporation limited by Share (finance), share ownership (i.e., one which is owned by its shareholders) whose shares may be traded on a stock market. The term is used in Germany, Austria, Switzerland (where it is equivalent to a ''S.A. (corporation), société anonyme'' or a ''società per azioni'') and South Tyrol for companies incorporated there. In the United Kingdom, the equivalent term is public limited company, and in the United States, while the terms "Incorporation (business), incorporated" or "corporation" are typically used, technically the more precise equivalent term is "joint-stock company". Meaning of the word The German word ''Aktiengesellschaft'' is a compound noun made up of two elements: ''Aktien'' meaning an acting part or shares, share, and ''Gesellschaft'', meaning company or society. English translations include ''share company'', or ''company limited by shares'', or joint-stock company. In German, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Düren
Düren (; Ripuarian language, Ripuarian: Düre) is a town in North Rhine-Westphalia, Germany, between Aachen and Cologne, on the river Rur (river), Rur. History Roman era The area of Düren was part of Gallia Belgica, more specifically the territory of the Eburones, a people who were described as both Belgae and Germanic peoples, Germani. It was conquered by the Roman Republic under Julius Caesar and became part of Germania inferior. Düren became a supply area for the rapidly growing Roman city of Cologne (Roman name Colonia Claudia Ara Agrippinensium). Furthermore, a few important Roman roads skirt Düren (including the road from Cologne to Jülich and Tongeren and the road from Cologne to Zülpich and Trier). By the 4th century, the area was settled by the Ripuarian Franks. The name ''villa duria'' occurred the first time in the Frankish Annals in the year 747. Frankish king Pippin the Short often visited Düren in the 8th century and held a few important conventions ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
