After the surface has a soft spot mold heat treatment, heat treatment on the wear resistance of the die, reducing heat treatment less mold life.

(1) causes
1) mold surface treatment prior to oxidation, rust spots and localized heat treatment decarbonization.
2) After the mold quenching, cooling heat treatment quenching medium fire inappropriate choice of quenching medium excessive impurities or aging.

(2) preventive measures
1) Heat treatment should die before descaling, rust, properly protected when quenching the mold surface, should be adopted in a vacuum furnace, salt bath furnaces and heating furnace protective atmosphere.
2) When the mold is cooled quenching, heat treatment should choose a suitable cooling medium, long-term use of the cooling medium should always be filtered or replaced regularly.