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Jominy En
Jominy test dimensioning Jominy test apparatus Used Jominy test-piece Hardenability is the depth to which a steel is hardened after putting it through a heat treatment process. It should not be confused with hardness, which is a measure of a sample's resistance to indentation or scratching. It is an important property for welding, since it is inversely proportional to weldability, that is, the ease of welding a material. Process When a hot steel work-piece is quenched, the area in contact with the water immediately cools and its temperature equilibrates with the quenching medium. The inner depths of the material however, do not cool so rapidly, and in work-pieces that are large, the cooling rate may be slow enough to allow the austenite to transform fully into a structure other than martensite or bainite. This results in a work-piece that does not have the same crystal structure throughout its entire depth; with a softer core and harder "shell". The softer core is some combi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementite
Cementite (or iron carbide) is a compound of iron and carbon, more precisely an intermediate transition metal carbide with the formula Fe3C. By weight, it is 6.67% carbon and 93.3% iron. It has an orthorhombic crystal structure. It is a hard, brittle material, normally classified as a ceramic in its pure form, and is a frequently found and important constituent in ferrous metallurgy. While cementite is present in most steels and cast irons, it is produced as a raw material in the iron carbide process, which belongs to the family of alternative ironmaking technologies. The name ''cementite'' originated from the theory of Floris Osmond and J. Werth, in which the structure of solidified steel consists of a kind of cellular tissue, with ferrite as the nucleus and Fe3C the envelope of the cells. The carbide therefore ''cemented'' the iron. Metallurgy In the iron–carbon system (i.e. plain-carbon steels and cast irons) it is a common constituent because ferrite can contain at m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASM International (society)
ASM International, formerly known as the American Society for Metals, is an association of materials-centric engineers and scientists. As the charitable arm of ASM, the ASM Materials Education Foundation also operates ASM Materials Camp in the summers for high school students and teachers. These camps are intended to educate the public about the materials field, and encourage young people to pursue careers in Materials science, materials science and engineering. History ASM has been in existence, under various names, since 1913, when it began as a local club in Detroit called the Steel Treaters Club. During World War I, the Steel Treaters Club became the Steel Treating Research Society, with groups in Detroit, Chicago, and Cleveland. After World War I, the Chicago group seceded and formed the American Steel Treaters Society. In 1920 the local chapters were reunified into the new American Society for Steel Treating (ASST). The society expanded its technical scope beyond steel d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Motors
General Motors Company (GM) is an American Multinational corporation, multinational Automotive industry, automotive manufacturing company headquartered in Detroit, Michigan, United States. The company is most known for owning and manufacturing four automobile brands: Chevrolet, Buick, GMC (marque), GMC, and Cadillac, each a separate division of GM. By total sales, it has continuously been the largest automaker in the United States, and was the List of manufacturers by motor vehicle production, largest in the world for 77 years before losing the top spot to Toyota in 2008. General Motors operates manufacturing plants in eight countries. In addition to its four core brands, GM also holds interests in Chinese brands Baojun and SAIC-GM-Wuling, Wuling via SAIC-GM-Wuling, SAIC-GM-Wuling Automobile. GM further owns GM Defense, a namesake defense vehicles division which produces military vehicles for the United States government and military, the vehicle safety, security, and information ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgy
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the science and the technology of metals, including the production of metals and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking. Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. A specialist practitioner of metallurgy is known as a metallurgist. The science of metallurgy is further subdivided into two broad categories: chemical metallurgy and physical metallurgy. Chemical metallurgy is chiefly concerned with the reduction and oxidation of metals, and the chemical performance of metals. Subjects of study in chemical metallurgy include mineral processing, the extraction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Alloys
This is a list of named alloys grouped alphabetically by the metal with the highest percentage. Within these headings, the alloys are also grouped alphabetically. Some of the main alloying elements are optionally listed after the alloy names. Alloys by base metal Aluminium * AA-8000: used for electrical building wire in the U.S. per the National Electrical Code (US), National Electrical Code, replacing AA-1350. * Al–Li (2.45% lithium): aerospace applications, including the Space Shuttle * Alnico (nickel, cobalt): used for permanent magnets * Aluminium–scandium alloys, Aluminium–Scandium (scandium) * Birmabright (magnesium, manganese): used in car bodies, mainly used by Land Rover cars. * Devarda's alloy (45% Al, 50% Cu, 5% Zn): chemical reducing agent. * Duralumin (copper) * Hiduminium or R.R. alloys (2% copper, iron, nickel): used in aircraft pistons * Hydronalium (up to 12% magnesium, 1% manganese): used in shipbuilding, resists seawater corrosion * Italma (3.5% magnesi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brine
Brine (or briny water) is a high-concentration solution of salt (typically sodium chloride or calcium chloride) in water. In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature). Brine forms naturally due to evaporation of ground saline water but it is also generated in the mining of sodium chloride. Brine is used for food processing and cooking (pickling and brining), for de-icing of roads and other structures, and in a number of technological processes. It is also a by-product of many industrial processes, such as desalination, so it requires wastewater treatment for proper disposal or further utilization (fresh water recovery). In nature Brines are produced in multiple ways in nature. Modification of seawater via evaporation results in the concentration of salts in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Heat
In thermodynamics, the specific heat capacity (symbol ) of a substance is the amount of heat that must be added to one unit of mass of the substance in order to cause an increase of one unit in temperature. It is also referred to as massic heat capacity or as the specific heat. More formally it is the heat capacity of a sample of the substance divided by the mass of the sample. The International System of Units, SI unit of specific heat capacity is joule per kelvin per kilogram, J⋅kg−1⋅K−1. For example, the heat required to raise the temperature of of water by is , so the specific heat capacity of water is . Specific heat capacity often varies with temperature, and is different for each state of matter. Liquid water has one of the highest specific heat capacities among common substances, about at 20 °C; but that of ice, just below 0 °C, is only . The specific heat capacities of iron, granite, and hydrogen gas are about 449 J⋅kg−1⋅K−1, 790 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Conductivity
The thermal conductivity of a material is a measure of its ability to heat conduction, conduct heat. It is commonly denoted by k, \lambda, or \kappa and is measured in W·m−1·K−1. Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal conductivity. For instance, metals typically have high thermal conductivity and are very efficient at conducting heat, while the opposite is true for insulating materials such as mineral wool or Styrofoam. Metals have this high thermal conductivity due to free electrons facilitating heat transfer. Correspondingly, materials of high thermal conductivity are widely used in heat sink applications, and materials of low thermal conductivity are used as thermal insulation. The reciprocal of thermal conductivity is called thermal resistivity. The defining equation for thermal conductivity is \mathbf = - k \nabla T, where \mathbf is the heat flux, k is the thermal conductivity, and \nabla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equivalent Carbon Content
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 wikt:alloyant, 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 (metalworking), casting cast iron. Steel In welding, equivalent carbon content (C.E) is used to understand how the different alloying elements affect hardness of the steel being welded. This is then directly related to hydrogen-induced cold cracking, which is the most common weld defect for steel, thus it is most commonly used to determine weldability. Higher concentrations of carbon and other alloying elements such as manganese, chromium, silicon, molybdenum, vanadium, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon
Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 electrons. It belongs to group 14 of the periodic table. Carbon makes up about 0.025 percent of Earth's crust. Three Isotopes of carbon, isotopes occur naturally, carbon-12, C and carbon-13, C being stable, while carbon-14, C is a radionuclide, decaying with a half-life of 5,700 years. Carbon is one of the timeline of chemical element discoveries#Pre-modern and early modern discoveries, few elements known since antiquity. Carbon is the 15th abundance of elements in Earth's crust, most abundant element in the Earth's crust, and the abundance of the chemical elements, fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. Carbon's abundance, its unique diversity of organic compounds, and its unusual abi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ferrous
In chemistry, iron(II) refers to the chemical element, element iron in its +2 oxidation number, oxidation state. The adjective ''ferrous'' or the prefix ''ferro-'' is often used to specify such compounds, as in ''ferrous chloride'' for iron(II) chloride (). The adjective ''ferric'' is used instead for iron(III) salts, containing the cation Fe3+. The word ''wikt:ferrous, ferrous'' is derived from the Latin word , meaning "iron". In salt (chemistry), ionic compounds (salts), such an atom may occur as a separate cation (positive ion) abbreviated as Fe2+, although more precise descriptions include other ligands such as water and halides. Iron(II) centres occur in coordination complexes, such as in the anion ferrocyanide, , where six cyanide ligands are bound the metal centre; or, in organometallic compounds, such as the ferrocene , where two cyclopentadienyl anions are bound to the FeII centre. Ferrous ions in biology All known forms of life require iron. Many proteins in living ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
