We are a mold manufacturer, and Plastic Pail Moulds are one of our products.
The working conditions of plastic molds are different from those of cold stamping dies. Generally, they must work at 150°C-200°C. In addition to being subjected to certain pressure, they also have to withstand temperature. According to the different use conditions and processing methods of plastic molding molds, the basic performance requirements of plastic mold steel are roughly summarized as follows:
1. Sufficient surface hardness and wear resistance
The hardness of the plastic mold is usually below 50-60HRC, and 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. Therefore, increasing the hardness of the mold is beneficial to improving its wear resistance.
2. Excellent machinability
In addition to EMD processing, most plastic molding molds require certain cutting processing and fitter repairs. 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<0.01nm. 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 far as possible. When the mold is formed by heat treatment, the linear expansion coefficient is small, the heat treatment deformation is small, and the size 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.
In addition, when selecting materials, you must also consider preventing scratches and bonding. If there is relative movement between the two surfaces, try to avoid selecting materials with the same structure. Under special conditions, one side can be plated or nitrided to make the two sides have different The surface structure.
In addition, 18L Pail Mould is also our product, welcome to consult and purchase.