Explanation

It is suitable for structural steel used to manufacture various sabot shells or parts with similar performance requirements. spring steel needs to have high elastic limit, high yield strength, high fatigue limit, and a certain impact toughness and plasticity. At the same time, because spring parts bear the maximum surface working stress under fatigue loads such as bending, torsion, tension and compression in the process of working, they also need to have good surface quality. The final heat treatment of spring steel usually adopts quenching and medium temperature tempering to obtain tempering troostite structure and obtain relatively high elasticity limit. In order to obtain very high yield strength and maintain proper toughness, spring steel mostly uses medium and high carbon content and needs to strictly control surface decarburization. In order to improve the surface bearing capacity and fatigue strength of spring parts, the spring products usually need to be shot blasting after the final heat treatment to cause the surface compressive stress state to inhibit the surface microcrack initiation. According to the chemical composition, the spring products can be divided into non alloy spring steel, alloy spring steel (GB/T1222-2007) and special spring steel. According to the shape requirements of spring products, spring steel is mostly supplied in the form of hot rolled flat steel (for leaf spring), bar or wire (for spiral spring, torsion bar spring, etc.) and cold rolled strip (for leaf spring).

Classification