Injection mould What are the manufacturer's requirements for materials

According to different working conditions and processing methods of injection mold, the basic performance requirements of injection mold steel are summarized: sufficient surface hardness and wear resistance. The hardness of injection mold steel is generally lower than 50-60hrc, and the injection mold after heat treatment should have sufficient surface hardness to ensure sufficient hardness of the injection mold. Because the injection mold is filled under high pressure, high friction and high flow, the precision of the injection mold is required to maintain the stability of the shape and dimensional precision of the mold and ensure the service life of the injection mold. The wear resistance of injection mold depends on the chemical composition and heat treatment hardness of steel, thus increasing the hardness of injection mold. 2. Good processing performance. Except for EMD processing, most plastic molding molds need some processing and assembly. In order to prolong the service life of the die, improve the cutting performance and reduce the surface roughness, the hardness of the die must be appropriate. Figure 3 shows. Good polishing performance. High quality plastic products require less cavity surface roughness. For example, the surface roughness of the injection cavity is required to be less than 0.1~0.25 Ra, while the optical surface is required to be Ra<0.01 nm. In order to reduce the surface roughness, the cavity must be polished. The selected steel requires less impurities, uniform microstructure, no fiber orientation, and no pitting or orange peel defects during polishing. Figure 4 shows. Good thermal stability. The shape of injection mold parts is more complex and difficult to quench. Therefore, good thermal stability should be selected as far as possible. After the mold is treated with small linear expansion coefficient, the heat treatment is small, the heat treatment deformation is small, and the temperature difference caused by the change rate is small. The structure and mold size are stable and can be reduced or no longer processed to ensure the dimensional accuracy and surface roughness of the injection mold.