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Ferrous Metals
As the most abundant of all commercial metals, alloys of iron and steel continue to cover a broad range of structural applications.
Iron ore constitutes about 5% of the earth's crust and is easy to convert to a useful form. Iron is obtained by fusing the ore to drive off oxygen, sulfur, and other impurities. The ore is melted in a furnace in direct contact with the fuel using limestone as a flux. The limestone combines with impurities and forms a slag, which is easily removed.
Adding carbon in small amounts reduces the melting point (2,777°F) of iron. All commercial forms of iron and steel contain carbon, which is an integral part of the metallurgy of iron and steel. Manipulation of atom-to-atom relationships between iron, carbon, and various alloying elements establishes the specific properties of ferrous metals. As atoms transform from one specific arrangement, or crystal lattice, to another, strength, toughness, impact resistance, hardness, ductility, and other properties are altered. The metallurgy of iron and steel is a study of how these atomic rearrangements take place, how they can be controlled, and which properties are affected.
Carbon Steel, Alloy Steel, Stainless Steel, Tool Steel, HSLA Steel, Steels for strength, Iron-based superalloys.
NonFerrous Metals
Nonferrous metals offer a wide variety of mechanical properties and material characteristics.
Nonferrous metals are specified for structural applications requiring reduced weight, higher strength, nonmagnetic properties, higher melting points, or resistance to chemical and atmospheric corrosion. They are also specified for electrical and electronic applications.
Material selection for a mechanical or structural application requires some important considerations, including how easily the material can be shaped into a finished part and how its properties can be either intentionally or inadvertently altered in the process. Depending on the end use, metals can be simply cast into the finished part, or cast into an intermediate form, such as an ingot, then worked, or wrought, by rolling, forging, extruding, or other deformation process. Although the same operations are used with ferrous as well as nonferrous metals and alloys, the reaction of nonferrous metals to these forming processes is often more severe. Consequently, properties may differ considerably between the cast and wrought forms of the same metal or alloy.
To shape both nonferrous and ferrous metals, designers use processes that range from casting and sintered powder metallurgy (P/M) to hot and cold working. Each forming method imparts unique physical and mechanical characteristics to the final component.
Beryllium, Copper, Magnesium, Nickel, Refractory Metals,Titanium, Zirconium
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