Analysis of the reasons for the failure of plastic molds. During the processing of the plastic mold factory, any deformation, cracks, skin oxidation, decarburization, etc. indicate that the mold has failed. The reason for the failure of the plastic mold is that the mold heat treatment process is not appropriate, such as the length of the holding time, the heating temperature, the cooling speed, and other improper setting of heat treatment parameters.
The reasons for the oxidation and decarburization of plastic molds are mainly because when the quenching of the mold is stopped at high temperature, it is not strictly controlled. Then, after the decarburization of the mold surface, due to the difference in the inner and outer layer structure, the larger tissue stress during cooling, Induces quenching cracks.
Another is about the heating speed. Because the mold steel contains many alloying elements and carbon, the thermal conductivity is poor. Therefore, the heating speed should not be too fast, and should be stopped slowly, so as to avoid deformation and cracking of the mold. When heating and quenching in an air furnace, in order to avoid oxidation and decarbonization, boxing is used to maintain the heating. At this time, the heating rate should not be too fast, and the diathermy should also be slow.
If the mold heating speed is too fast, then the heat penetration is also fast, the mold will produce a lot of thermal stress. If the control is not good, things like cracks or deformations can easily happen.
Post time: Jul-17-2020