Other Definitions
austenite (dict)
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AusteniteAustenite is a metallic, non-magnetic solid solution of carbon and iron that exists in steel above the critical temperature of 1333°F (about 723°C). It is named after Sir W.C. Roberts-Austen. Its face-centred cubic (FCC) structure allows it to hold a high proportion of carbon. As it cools, it either breaks down into a mixture of ferrite and cementite (often in special forms such as pearlite and bainite), or undergoes a slight lattice distortion known as martensitic transformation. The rate of cooling determines the relative proportions of these materials and therefore the mechanical properties (e.g. hardness, tensile strength) of the steel. Quenching (to induce martensitic transformation), follwed by tempering (to break down some martensite and retained austenite), is the most common heat treatment for high-performance steels. The addition of certain other metals, such as manganese, nickel and chromium, 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.
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