Processing CPU elastomer products is inseparable from the mold. For processing methods such as normal pressure casting and pressure molding, which are often used, the requirements for molds are also different. For normal pressure open casting molding, since external pressure is not required, the strength of the mold material is not a key consideration. The problem, as long as the size is stable and the heat resistance is appropriate, it can be used as a mold material. For example: silicone rubber, epoxy resin, nylon 66, phenolic resin, polytetrafluoroethylene, reinforced polypropylene, low melting point alloys, etc. can all be used as mold materials. But in industrial production, from the durability

Considering that only metal molds are most suitable. For press molding, the mold used must be made of metal. However, metal molds are relatively heavy and costly, and specific problems should be analyzed in detail in production. At present, more and more plastics such as reinforced polypropylene molds are used for atmospheric vulcanization.

The basic requirements for materials. According to the structure and use requirements of the mold, the reasonable selection of mold materials is one of the important links in the mold design work. The steel used in the mold basically has the following properties.

① Good processing performance, small heat treatment deformation, especially the latter is the most important. In order to facilitate mechanical and fitter processing, the hardness of mold parts after quenching and tempering should be 30HRC.

② Good polishing performance. The most basic requirement for plastic parts is good surface condition. The CPU elastomer and steel have a strong bonding force, so the mold cavity must be well polished, and the selected steel should not have rough impurities and pores.

③ Good abrasion resistance. The surface finish of the rubber part is directly related to the dimensional accuracy and surface wear resistance of the mold, and the wear resistance of the mold surface is directly related to the surface hardness of the mold.

④ High core strength. In addition to surface hardness, the selected steel should have sufficient core strength.

⑤Good corrosion resistance.