The heat treatment of stainless steel balls must first […]
The heat treatment of stainless steel balls must first understand why heat treatment. In terms of metallographic structure, stainless steel balls are divided into austenitic stainless steel balls, martensitic stainless steel balls, ferritic stainless steel balls, and heat treatment of balls of different materials. There are different ways:
1. The purpose of heat treatment of austenitic stainless steel beads is to remove the magnetic force, because the steel ball will produce working magnetism in the process of cold heading or grinding, and the metallographic structure will gradually change from austenite to martensite, which is anti-corrosion. The performance will also deteriorate, so the heat treatment can remove the magnetism on the one hand, and on the other hand, it can also be transformed into the original austenite. The correct heat treatment method, the electric furnace temperature is increased to 850 degrees, and the stainless steel ball insulation is usually 1- 2 hours, then pour it into cold water to cool quickly, so that the magnetism can usually be removed.
2. The purpose of heat treatment of martensitic stainless steel balls is to increase the hardness, thereby enhancing the wear resistance of the stainless steel balls and prolonging the life of the workpiece: because this type of stainless steel balls are high-carbon and high-chromium, these two elements are a pair of contradictions. , Due to the high carbon content and chromium content, it is easy to cause uneven distribution of chromium elements, thereby affecting the rust-proof performance of stainless steel.
420 stainless steel ball heat treatment temperature, 2-5MM 1050 degrees
5-50MM around 1080 degrees
Then pour into oil, the hardness after quenching is usually HRC48-55
440C stainless steel bead heat treatment temperature: about 2-5MM 1100 degrees
5-50MM around 1150 degrees
Then pour it into the oil. The hardness after quenching is usually HRC57-62
3. Ferritic stainless steel beads do not require heat treatment.More about:304 STAINLESS STEEL BEARING BALLS