How to deal with the deformation of plastic mold in heat treatment
- (1) Reasonable selection of materials. For precision and complex molds, choose good-deformation mold steel (such as air-quenched steel), and mold steel with severe carbide segregation should be forged reasonably and tempered and heat-treated, and large and unforgeable mold steels can be solid solution double Refine heat treatment.
- (2) The mold structure design should be reasonable, the thickness should not be too wide, and the shape should be symmetrical. For the mold with large deformation, the deformation rule should be mastered, and the processing allowance should be reserved. For large, precise and complex molds, a combined structure can be used.
- (3) Precise and complex molds should be pre-heat-treated to eliminate the residual stress generated during the machining process.
- (4) Reasonably select the heating temperature and control the heating speed. For precision and complex molds, slow heating, preheating and other balanced heating methods can be used to reduce mold heat treatment deformation.
- (5) On the premise of ensuring the hardness of the mold, try to adopt the pre-cooling, stepped cooling quenching or warm quenching process.
- (6) For precision and complex molds, as far as conditions permit, try to use vacuum heating quenching and cryogenic treatment after quenching.
- (7) For some sophisticated molds, pre-heat treatment, aging heat treatment, tempering and nitridation heat treatment can be used to control the precision of the mold.
- (8) When repairing defects such as die blisters, blowholes, and abrasion, use cold welding machines and other repair equipment with small thermal impact to avoid deformation during the repair process. In addition, the correct heat treatment process operations (such as plugging holes, binding holes, mechanical fixing, suitable heating methods, correct selection of the cooling direction of the mold and the direction of movement in the cooling medium, etc.) and a reasonable tempering heat treatment process also reduce precision and complexity Effective measures for mold deformation.
