1. Hard mold
This is the steel plate used in the plastic parts of the injection mold. After buying it from the supplier, it needs to be heat-treated, for example, quenching and carburizing to meet the requirements of use. Such an injection mold is called a hard mold. For example, the inner film part usually adopts H13 steel, 420 steel, S136 steel.

2. Soft film
The steel used in the inner mold can directly meet the requirements of use without heat treatment after purchase. Such injection molding is called soft film, such as P20 steel, ace steel, 420 steel, NAK80 and so on for the inner mold.

Of course, the choice of these steels needs to be chosen by the customer, depending on whether the customer has special requirements for the life of the mold, the surface of the mold, and so on. Combining these, you can choose a steel that best suits your mold.