Spring wire shall have high tensile strength, elastic limit, endurance and fatigue strength, and be resistant to shock and oscillation. The objectives of strength and endurance, especially the prevention of alteration cracks, are key to the consumption of spring steel wires. The inner and outer quality of wire rod directly affect the function of steel wire.
The spring steel wire is made of high carbon and high quality carbon structural steel or carbon tool steel wire rod, and its chemical composition, gas content and non-metallic inclusion must be strictly controlled according to the use of the spring. In order to reduce the appearance of shortcomings and decarbonization layer, the consumption of rod billet to stop surface grinding, if necessary, but also stop peeling.
Wire rod to stop normalizing or soxaustenitizing treatment, large specifications with spheroidizing annealing instead. In the middle, especially before the waste product drawing process of thermal disposal throughout the selection of soxaustenitizing disposal. Decarbonization should be prevented during thermal disposal. Sulfuric acid or hydrochloric acid pickling was used to remove the oxide sheet after hot treatment. Coating (see lubrication carrier) can be dipped in lime, phosphating, borax disposal or copper plating.
The drawing process of waste product drawing process has a great influence on product function. Generally, large total surface reduction rate (see area reduction rate) and small pass surface reduction rate (about ≤23%) are selected to ensure the tolerance of products. About high strength spring steel wire, the exit temperature of each pass steel wire should be controlled when drawing below 150℃, to prevent the steel wire from changing cracks due to strain aging, which is the main disadvantage of steel wire obsoletion.
Post time: 19-07-22