The purpose of mold hardening and strengthening is to increase the service life of the mold. The generally adopted method is nitriding. The advantage of nitriding is that the heating temperature of the manufactured mold is low, and the mold is not easy to deform. Especially some molds that have been tested before heat treatment are particularly important. If the car mold is quenched as usual, the tried mold will not be assembled. This method is commonly used in die-casting molds. If your mold has already been formed, I am afraid that the flash will make the mold parting surface pit by pit during production. I can give you the simplest method, which is nitriding. The price is cheap and easy to use, but the premise is that your mold has been formed and is not being processed. The purpose of surface hardening and strengthening of various molds is to extend life. The most common method now is surface dip fire treatment, but the effect is limited. Secondly, the carburizing treatment can improve a lot, and then the surface coating effect is the best. At present, the widely used coating material is titanium, and the best coating for automobile molds is CVD, which can reach the hardness of diamond, which is the most Ideal coating material, but the cost is high.