Plastic molds are tools that are matched with plastic molding machines in the plastic processing industry to give plastic products a complete configuration and precise dimensions. So what are the requirements of plastic molds for material selection?
Precision plastic mold manufacturer
1. Sufficient surface hardness and wear resistance
The hardness of the plastic mold is usually below 50-60 HRC. The heat-treated mold should have sufficient surface hardness to ensure that the mold has sufficient rigidity. When the mold is working, due to the filling and flow of plastic, it has to withstand greater compressive stress and friction. It is required that the mold maintain the accuracy of the shape and the stability of the dimensional accuracy to ensure that the mold has sufficient service life. The wear resistance of the mold depends on the chemical composition and heat treatment hardness of the steel, so increasing the hardness of the mold is beneficial to improve its wear resistance.
2, excellent machinability
Most plastic molding molds require certain cutting processing and fitter repairs in addition to EMD processing. In order to extend the service life of cutting tools, improve cutting performance, and reduce surface roughness, the hardness of the steel used for plastic molds must be appropriate.
3, good polishing performance
High-quality plastic products require small roughness on the surface of the cavity. For example, the surface roughness value of the injection mold cavity is required to be less than Ra0.1～0.25, and the optical surface requires Ra<0.01 nm. The cavity must be polished to reduce the surface roughness value. For this reason, the selected steel requires less material impurities, fine and uniform structure, no fiber directionality, and no pitting or orange peel defects during polishing.
4, good thermal stability
The shape of the parts of the plastic injection mold is often complicated and difficult to process after quenching. Therefore, it should be selected with good thermal stability as much as possible. When the mold is formed by heat treatment, the linear expansion coefficient is small, the heat treatment deformation is small, and the dimensional change caused by the temperature difference The rate is small, the metallographic structure and the mold size are stable, and the processing can be reduced or no longer needed to ensure the mold size accuracy and surface roughness requirements.
The above is some introduction about the main material selection requirements of Dongguan Sen Entropy Plastic Mold, I hope it will be helpful to everyone.
skype