Rapid cooling of steels

Rapid cooling will produce different microstructures from those obtained by slow cooling, only a few examples of which are described here. Rapidly cooling the homogeneous alloy austenite, with the fee structure, to room temperature (a process called 

The formation of martensite is extremely rapid and only a slight displacement of atoms takes place. In particular, the carbon atoms have no time to diffuse any great distance, and the iron atoms do not have time to shear to form cementite. Once a nucleus of a martensite crystal forms, it will 

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