Different options for various spring materials

The choice of spring material should be determined according to the nature of the spring's load, the state of stress, the size of the stress, the working temperature, the environmental medium, the service life, the required process performance for electrical conductivity, material source and price.

When determining the shape and size of the material section, the series of sizes specified in the national standards and ministerial standards should be preferred, and the selection of non-standard series of materials should be avoided as much as possible.

Medium and small springs, especially helical tension springs, should preferably use reinforced steel wire, lead bath isothermal cold drawn steel wire and oil quenched and tempered steel wire, which have high strength and good surface quality, and the fatigue performance is higher than that of ordinary quenching. Tempered steel wire, simple processing, good manufacturability and stable quality.

Carbon spring steel wire and piano wire produce large residual stress after cold drawing. After processing the spring, there is a large residual stress, and the dimensional change after tempering is large, so it is difficult to control the dimensional accuracy. The oil quenched and tempered steel wire is modulated and strengthened after the steel wire is drawn to the specified size, basically there is no residual stress. Reinforced steel wire.

For large and medium-sized springs, cold-drawn or cold-drawn polished steel should be used for those with high load accuracy and stress. For springs with lower load accuracy and stress, hot-rolled steel can be used.

Leaf springs generally use flat steels of 55Si2Mn, 60Si2MnA. 55SiMnVB, 55SiMnMoV. 60CrMn, 60CrMnB and other grades.

The material cross-section of the coil spring should preferably be a circular cross-section. Square and rectangular section materials have strong bearing capacity, good impact resistance, and can miniaturize the spring, but the material source is small. And the price is high, except for special needs, generally try not to use this material. In recent years, the development of rolling flat steel wire instead of trapezoidal steel wire has achieved good results.