In fact, the structures of a die-casting mold and an injection molding mold are the same. In other words, if you can make injection molding mold, you should be able to make die-casting mold.
1. The injection pressure of die-casting mold is large, so the template should be relatively thick to prevent deformation.
2. The sprue of the die-casting mold is different from that of injection molding mold, so it is required to make a sprue spreader to decentralize the high pressure of material flow.
3. The core of die-casting mold does not need quenching, because the temperature in the die cavity exceeds 700 Celsius degrees when die-casting. Therefore, each molding is equivalent to quenching once and the molding cavity will become harder and harder. As to the general injection mold, it should be quenched to above HRC52.
4. Generally, the molding cavity of die-casting mold is nitrided to prevent the alloy from sticking to the cavity.
5. Generally, the corrosion of die-casting mold is relatively serious, so the outer surface is treated with bluing.
6. Compared with the injection molding mold, the fitting clearance of the movable fitting part (such as core-pulling slider) of the die-casting mold is larger than that of the injection molding mold, because the high temperature of the die-casting process will cause thermal expansion. If the clearance is too small, the mold will be stuck.
7. The process requirement for the die joints of die-casting molds are higher because the fluidity of alloy is much better than that of injection molding mold. The material flow with high temperature and high pressure flying out of the die joints will be very dangerous.
8. The injection molding mold can exhaust air by means of the centre and die joint. The die-casting mold must be provided with air vent and slag trap (collecting the stub bar of cold material).