1. a reasonable selection. Density of complex micro-deformation of the mold to use good quality tool steel, carbide segregation serious forged and tempered tool steel heat treating, for large or cannot be forged tool steel solution heat treatment of dual refinement. 2. mold design to be reasonable, symmetrical, of large deformation of the mold master law, reserved for machining, mold can be used for large and sophisticated structure. 4. reasonable selecting heating and temperature control temperature, slow heating, Preheat and uniform heating method to reduce deformation of heat treatment. 5. under the permit conditions, as far as possible by vacuum heating quenched and tempered after cryogenic treatment. 3. this kind of mold you want to pre-heat.