spring steel wire should be based on the load, stress, size, temperature, environment media, life, the conductive magnetic requirements, process performance, material sources, prices and other factors.
When choosing the spring steel wire's cross section shape and size, you'd better choose the size provide by the national standards.
You should choose the spring steel wire after the strengthen treatment for the medium and small springs, especially the coiled tension spring. This steel wire has high strength, good surface quality and simple processing.
Medium and large springs, which have high requirements to load precision and stress; we should use the cold drawn spring steel wire or polished steel wire after cold drawing.
We should choose spring steel wire with circular cross-section for coil spring. Square cross-section wire has a good ability to withstand, but the source of material is few and the price is high. Except in special need, we don't use this spring steel wire.
The spring steel wire working at a high temperature requires better thermal stability, the ability of resist to relaxation, creep and corrosion. However, the one working at a low temperature requires good low temperature toughness.
Stainless steel spring wires usually use for the spring working in the acid exposure environment. The alloy spring steel wires are preferred of the spring use in the instrument which requires procession is uneasy to change with enviroment.
Now you have the idea to choose the appropriate spring steel wire.