431 stainless steel is a high hardness, high strength martensitic stainless steel. The corrosion resistance and mechanical strength of 431 stainless steel can be improved by adding molybdenum and chromium. This stainless steel has excellent mechanical properties, grinding and wear resistance, and has good corrosion resistance and heat treatment performance. Therefore, it is often used in the manufacture of high-strength, high wear-resistant parts, such as bearings, valves, threads, bolts and connections. In addition, 431 stainless steel is also suitable for the manufacture of high wear-resistant knives, molds and clamps. It should be noted that the welding performance of 431 stainless steel is poor, so it is necessary to handle it carefully and choose suitable welding materials when welding.