How To Prevent Deformation During Heat Treatment Of Plastic Molds

The heat treatment process is an indispensable step in the manufacture of plastic molds, and it can achieve the desired hardness of another mold steel. However, deformation will occur during processing, so how to prevent this undesirable phenomenon? In general, the following methods can be adopted to prevent deformation problems during the heat treatment of plastic molds.

(1) Select the appropriate steel material; for precision and complex plastic molds, mold steel of good material should be selected. The mold steel used must have good cutting performance and toughness, and it is not easy to deform.

(2) The mold structure is designed reasonably, the wall thickness is uniform, and the shape is symmetrical. It is necessary to reserve machining allowance when designing. For large, precise and complex plastic molds, a combined structure can be adopted.

(3) It is necessary to perform heat treatment in advance for precision and complex plastic molds to eliminate residual stress generated during machining.

(4) Reasonably select the processing temperature and control the heating speed. For sophisticated plastic molds, slow heating, preheating, and other balanced heating methods can be used to reduce the heat treatment deformation of the mold.

(5) On the premise of ensuring the hardness of the plastic mold, try to use pre-cooling, staged cooling quenching or warm quenching as far as possible.

(6) For sophisticated plastic molds, vacuum heating quenching and cryogenic treatment after quenching are used as far as possible under the prerequisite conditions.

(7) For some precision and complicated molds, pre-heat treatment, aging heat treatment, and quenching and nitridation heat treatment can be used to control the precision of plastic molds.

(8) When repairing defects such as blow holes and abrasion of plastic molds, use repair equipment with small thermal effects to avoid the problem of deformation during the repair process.