Mold is an important basic process equipment in manufacturing technology. The quality of mold products is not only related to the quality and performance of the products, but also directly affects the manufacturing cost and efficiency. In the mold products of the automobile, home appliance, communication and instrumentation, plastics, metal processing and other industries, cold-working molds occupy a considerable market.
Cold work dies mainly complete cold forming of metal or non-metal materials, including cold stamping, cold extrusion and cold heading dies. Compared with hot work dies, these molds have large working loads, dimensional accuracy, high surface quality requirements, and large processing batches, most of which are final products. In order to meet the requirements of this working condition, cold working molds are often made of high carbon or high alloy steel, and the working hardness is 58-60HRC.
The commonly used cold work die steel requires sufficient strength (including tensile, compressive and flexural strength), sufficient toughness, sufficient hardness and wear resistance (especially surface), and sufficient fatigue resistance (especially It is a multi-crush fatigue performance); for large-load cold extrusion and cold forging forming dies, heat is generated due to severe deformation (about 300 ° C), and the material is required to have higher resistance to deformation and fracture.
According to the statistics of the use and failure of cold working molds in the past, the quality of the mold depends largely on the selection of the mold and the process. According to the conditions of the mold, the correct selection of the material of the mold and the formulation of a reasonable treatment process are very important to reduce the early failure of the cold working mold.