As the purpose of precision casting, heat treatment is very much, the basic can be divided into two categories, the first is the structure of the organization will not change through heat treatment or should not be changed, the second is the basic organizational structure changes. The first heat treatment procedure is mainly used to eliminate the internal stress, which is caused by the cooling conditions and conditions in the stainless steel casting process. Organization, strength and other mechanical properties, not due to heat treatment and significant changes.
For the second type of heat treatment and the main base organizations have undergone significant changes can be broadly divided into five categories:
1, softening annealing: its main purpose is to break down the carbide, its hardness is reduced, and improve the processing performance, for ductile iron, its purpose is to get more ferrite.
2, normalizing treatment: the main purpose is to obtain pearlite and sorbite to improve the mechanical properties of stainless steel casting.
3, quenching: mainly in order to obtain a higher hardness or wear strength, while the very high surface wear characteristics.
4, surface hardening treatment: mainly to obtain the surface hardened layer, while the very high surface wear characteristics.
5, precipitation hardening treatment: mainly for the high strength and elongation does not occur so drastic changes.