Problems of heat treatment of plastic molds

Publication date:

2024-12-17

Press mold heat treatment is an important means of increasing hardness

Problems of heat treatment of plastic molds

Heat treatment of the mold is an important means of increasing the hardness of the steel material, usually after the rough machining of the mold.

1) Strong segregation of reticular carbide in the mold material.
2) The presence of stresses from machining or cold forming in the mold.
3) Incorrect heat treatment operation of the mold (too fast heating or cooling, selection of quenching and cooling medium, too low cooling temperature, too long cooling time, etc.).
4) Complex shape of the mold, uneven thickness, sharp corners, thin threaded holes, etc., resulting in excessive thermal stress and residual stress in the material.
5) Too high heating temperature during the hardening process of the mold, which can lead to overheating or burning.
6) Tempering during hardening of the mold is not timely or the insulation time during hardening is insufficient.
7) Repair of the mold by hardening and heating, without intermediate annealing and re-hardening.
8) Heat treatment of the mold, incorrect grinding process.
9) Heat treatment of the mold after electro-erosion processing, high tensile stress and microcracks in the hardened layer.