Effect of Tempering Temperature on Microstructure and Corrosion Resistance of Plastic Mould Steel S136 SUP

Since the 21st century, the development of automotive and home appliance industries has greatly contributed to the prosperity of the plastics industry, which has led to an increasing demand for molding molds. In the production process, the molds will be impacted, worn and corroded, especially in the production of plastic products made of PVC, fluoroplastics and flame retardant ABS, etc. The molds will be corroded by the corrosive gases generated such as hydrogen chloride, hydrogen fluoride and sulfur dioxide, which requires plastic molds to have a certain degree of corrosion resistance while ensuring strong toughness.S136 SUP is a modified martensitic stainless steel based on S136 from ASSAB, Sweden, which has fine-tuned the content ratio of some elements to ensure a certain strength and high toughness at the same time. The chemical composition, heat treatment and microstructure of the steel have a certain influence on its corrosion resistance, and the tempering temperature of the heat treatment has a greater influence on the corrosion resistance of martensitic stainless steel. Therefore, in this paper, the microstructure and corrosion resistance of S136 SUP at different tempering temperatures are explored and studied.