Performance requirements for the hottest die steel

Performance requirements of die steel (III)

b hardenability and hardenability

hardenability mainly depends on the chemical composition of the steel and the original microstructure state before quenching; Hardenability mainly depends on the carbon content in steel. For most cold working die steels, hardenability is often one of the main considerations. For hot work die steel and plastic die steel, the maintenance of oil source for general die experiment: the size is large, especially for the manufacture of large dies, its hardenability is more important. In addition, for various molds with complex shapes that are prone to heat treatment deformation, in order to reduce quenching deformation, quenchants with weak cooling capacity, such as air cooling, oil cooling or salt bath cooling, are often used as much as possible. In order to obtain the required hardness and hardening layer depth, die steel with good hardenability is needed

c quenching temperature and heat treatment deformation

in order to facilitate production, the quenching temperature range of die steel is required to be widened as much as possible, especially when the die is locally quenched by flame heating, because it is difficult to accurately measure and control the temperature, it is required that the die steel has a wider quenching temperature "C" representing China (China)

during the heat treatment, especially in the quenching process, the mold will produce volume changes, shape warpage, distortion, etc. in order to ensure the quality of the mold, the heat treatment deformation of the mold steel is required to be small, especially for the precision mold with complex shape, it is difficult to repair after quenching, and the requirements for the degree of heat treatment deformation are more stringent, so the micro deformation mold steel should be selected for manufacturing

d oxidation and decarburization sensitivity

during the heating process, if oxidation and decarburization occur, its hardness, wear resistance, service performance and service life will be reduced; Therefore, die steel is required to be sensitive to oxidation and decarburization. For die steel with high molybdenum content, due to its strong sensitivity to oxidation and decarburization, special heat treatment, such as vacuum heat treatment Controlled atmosphere heat treatment "1 straight, salt bath heat treatment, etc.

other factors

let's talk about the tensile strength of materials

when selecting die steel, in addition to the use performance and process performance, we must also consider the versatility of die steel and the price of steel. Generally, the amount of die steel is small. In order to facilitate material preparation, we should consider the versatility of steel as much as possible, and try to use the general-purpose die steel produced in large quantities, so as to facilitate procurement Material preparation and material management. In addition, a comprehensive economic analysis must be carried out, taking into account the manufacturing cost of the mold, the production batch of the workpiece and the mold cost allocated to each workpiece. From the technical and economic aspects of comprehensive analysis, in order to finally select a reasonable mold material