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Hardenability
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 Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Co ..., 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 th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Weldability
The weldability, also known as joinability,. of a material refers to its ability to be welded. Many metals and thermoplastics can be welded, but some are easier to weld than others (see Rheological weldability). A material's weldability is used to determine the welding process and to compare the final weld quality to other materials. Weldability is often hard to define quantitatively, so most standards define it qualitatively. For instance the International Organization for Standardization (ISO) defines weldability in ISO standard 581-1980 as: "Metallic material is considered to be susceptible to welding to an established extent with given processes and for given purposes when welding provides metal integrity by a corresponding technological process for welded parts to meet technical requirements as to their own qualities as well as to their influence on a structure they form." Other welding organizations define it similarly. Steels For steel there are three major failure modes b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Treatment
Heat treating (or heat treatment) is a group of industrial, thermal and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass. Heat treatment involves the use of heating or chilling, normally to extreme temperatures, to achieve the desired result such as hardening or softening of a material. Heat treatment techniques include annealing, case hardening, precipitation strengthening, tempering, carburizing, normalizing and quenching. Although the term ''heat treatment'' applies only to processes where the heating and cooling are done for the specific purpose of altering properties intentionally, heating and cooling often occur incidentally during other manufacturing processes such as hot forming or welding. Physical processes Photomicrographs of steel. Top: In annealed (slowly cooled) steel, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Austenite
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. Allotrope of iron From alpha iron undergoes a phase transition from body-centered cubic (BCC) to the face-centered cubic (FCC) configuration of gamma iron, also called austenite. This is similarly soft and ductile but can dissolve considerably more carbon (as much as 2.03% by mass at ). This gamma form of iron is present in the most commonly used type of stainless steel for making hospital and food-service equipment. Material Austenitiz ... [...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] |
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] |
Steel
Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength and low raw material cost, steel is one of the most commonly manufactured materials in the world. Steel is used in structures (as concrete Rebar, reinforcing rods), in Bridge, bridges, infrastructure, Tool, tools, Ship, ships, Train, trains, Car, cars, Bicycle, bicycles, Machine, machines, Home appliance, electrical appliances, furniture, and Weapon, weapons. Iron is always the main element in steel, but other elements are used to produce various grades of steel demonstrating altered material, mechanical, and microstructural properties. Stainless steels, for example, typically contain 18% chromium and exhibit improved corrosion and Redox, oxidation resistance versus its carbon steel counterpart. Under atmospheric pressures, steels generally ... [...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] |
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] |
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] |
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] |
