In order to improve the wear resistance and corrosion resistance of the mold surface, it is often subjected to appropriate surface treatment.
Chromium plating is one of the most used surface treatment methods. The chromium plating layer has strong passivation ability in the atmosphere, can maintain the metallic luster for a long time, and no chemical reaction occurs in a variety of acidic media. The coating hardness of 1000HV is equivalent to HRC65, so it has excellent wear resistance. The chromium plating layer also has high heat resistance, and its appearance and hardness have not changed significantly when heated to 500 degrees in air.
Nitriding has the advantages of processing temperature (generally 550~570 degrees), very little mold deformation and high hardness of the infiltrated layer (up to 1000~1200HV, equivalent to HRC65~72), so it is also very suitable for surface treatment of molded plastic products molds . Steels containing alloy elements such as chromium, molybdenum, aluminum, vanadium, and titanium have better nitriding properties than carbon steels. Nitriding treatment when used as SMC molds can greatly improve wear resistance.