• 1.Introduction of mold casting process
  

Stamping die is a kind of special process equipment that processes materials (metal or non-metal) into finished products (or semi-finished products) of automobile cover parts in cold stamping process. Its main structure (die base, pressing plate, concave die, punch die, etc.) is mainly formed by casting, as shown in Figure 1. 

Stamping die has a perfect casting process from design drawings to finished castings, among which the most important parts are foam mold (FMC mold) manufacturing, process formulation manufacturing, sand filling modeling and post-casting stress management. 

Through the selection of different casting materials and the corresponding heat treatment process, it can meet the requirements of high strength, high hardness, high wear resistance and high impact toughness of different functional parts of the mold.  HT300 (gray iron) material is used for conventional structural parts with low hardness and wear resistance, such as mould base body and general pressing plate.  Icd-5 (cast steel 7CrSiMnMoV), QT600 (ductile iron) and other materials are selected for the functional parts with high requirements for hardness, wear resistance and impact resistance, such as bridge pressing plate, trimming punch, trimming/shaping/flanging insert, as shown in Table 1.