What changes occur after heat treatment of precision castings?

Because of its good performance and accurate specifications, precision castings can be used in various fields without production or processing. The actual performance requirements of precision castings after production and processing are different. Some precision castings require heat treatment to give the product The workpiece has stronger strength and other physical properties.

There are many methods of heat treatment. Basically, the key points can be divided into two categories. One is that the structure of the mechanism is not easy to change or should not change due to heat treatment, and 2. the main organizational structure changes. In view of the prominent changes in the mechanism during the heat treatment process , can be roughly divided into 5 ways:

1. Softening and quenching: Its significance depends on dissolving cementite, reducing its strength, and improving production and processing performance. For ductile iron, its goal is to obtain more and more metallographic structures.

2. Normalizing treatment: The main goal is to obtain pearlite and sorbite structures to improve the mechanical equipment performance of stainless steel castings.

3. Heat treatment solution: The key is to obtain higher strength or wear compressive strength while achieving higher surface wear resistance.

4. Surface hardening solution: The key is to obtain a surface hardening layer and obtain high surface wear resistance at the same time.

5. Solve the problem of precipitation hardening: the key is to obtain high toughness without drastic changes in elongation.