Heat treatment can be used to strengthen the technology of torsion spring
1) Protective atmosphere heat treatment. In my country, the heat treatment of torsion springs, oil-quenched and tempered steel wires and toughened steel with a wire less than 15mm use protective atmosphere heat treatment. Protective atmosphere heat treatment can eliminate surface decarburization and oxidation, and improve the surface of the material quality.
2) Induction heating or protective atmosphere induction heating heat treatment. This process is generally carried out on the wire before the spiral torsion spring is formed. Some torsion spring factories combine the heat treatment of the wire material and the production of torsion springs to reduce costs. Induction heating treatment has more advantages. Good strengthening effect and fast induction heating speed can help refine crystal grains and reduce surface decarburization, which can give full play to and improve the strength and toughness of the material.
3) Surface nitriding heat treatment technology. In recent years, high-stress valve torsion springs or other high-stress clutch torsion springs have also adopted surface nitriding technology to achieve reliable fatigue life. Now the more advanced technology is low-temperature gas nitriding technology , The general nitriding temperature is (450~470)℃, and the gas nitriding time is (5~20)h.