What heat treatment should be used to produce a uniform grai

What heat treatment should be used to produce a uniform grain size? What heat treatment should be used to produce the hardest steel? What heat treatment should be used to produce the hardest surface on a metal?

Solution

1) Normalizing is the heat treatment process which produce uniform grain size and composition throughout the alloy , in this process heating the steel above critical temperature , holding for a period of time long enough for transformation to occur ,and air cooling . Normalized heat treatment establishes a more uniform carbide size and distribution which facilitates later heat treatment operations and produce final product

2) Carburizing is the heat tretment process which produce hardest steel , in this process metal is heated in presence of carbon monoxide , charcoal which leeds metal to become harder , the presence of carbon the surface become hard due to transformation from austenite to martensite .Depending on carburizing time and temperature incerase the depth of carbon diffusion

3) Induction hardening is the heat treatment process to produce the hardest surface on a metal , it is a surface hardening technique which the surace of metal is heated very quickly using no-contact method of induction heating . the alloy is then quenched ,producing a martensite transformation at the surface while leaving the underlying metal unchanged this leeds to very hard , wear resistant surface with proper toughness