Heat Treatment of Precision Castings

Due to different purposes of precision castings, there are many heat treatments, which can be basically divided into two categories. The first is that the microstructure will not change or should not change through heat treatment, and the second is that the basic microstructure will change. The first heat treatment procedure is mainly used to eliminate internal stress, which is caused by different cooling conditions and conditions during stainless Steel Casting. The structure, strength and other mechanical properties will not change significantly due to heat treatment.

For the second type of heat treatment, Al Qaeda has changed significantly, which can be roughly divided into five categories:

1. Softening annealing: its purpose is mainly to decompose carbides, reduce their hardness and improve the machinability. For nodular cast iron, its purpose is to obtain more ferrite structure.

2. Normalizing treatment: the main purpose is to obtain pearlite and sorbite structure and improve the mechanical properties of stainless steel casting.

3. Quenching treatment: mainly to obtain higher hardness or wear strength and very high surface wear resistance.

4. Surface hardening treatment: mainly to obtain surface hardening layer and high surface wear resistance.

5. Precipitation hardening treatment: it is mainly to obtain high strength without drastic change in elongation.