|MadSci Network: Engineering|
Hi, The steel goes through a phase transformation, it changes crystal structure. As an example, in austenitic stainless steel, both austenite and martensite are present. At the elevated temperature used to form the steel, the austenite is more stable and is the dominant component. At lower temperatures, the martensite phase becomes more stable, and the steel transforms from austenite to martensite. The temperature at which the martensite transforms back into austenite is typically much higher than room temperature, so the steel remains martensitic after cooling. The martensite is harder than the austenite, and so wear resistance is improved. Bob Novak Specialist - Process R&D Carpenter Technology
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