The first type is a material that does not require quenching and that requires only stress relief annealing after the spring is formed. These materials are mainly reinforced steel wire, carbon steel wire, piano wire, spring stainless steel wire and various oil quenched and tempered steel wire.

The second type is a material that requires only aging treatment after the spring is formed, and has a beryllium bronze wire, an alloy for a spring element, and the like.

The third type is a material that has to be quenched and tempered. These are mainly annealed and hot rolled materials, such as hot rolled spring steel wire, silicon manganese spring steel wire, chrome vanadium spring steel wire, chrome silicon spring steel wire, and the like.

With the development of the metallurgical industry and the continuous improvement of spring performance requirements, in order to reduce equipment investment, reduce production costs, shorten production cycle, improve product quality and economic benefits, it is necessary to design and manufacture only need to perform stress relief annealing after forming. The material is used to make the spring, the first type. The material to be quenched and tempered after winding and forming, that is, the third type should not be used as much as possible.

The second type of aging treatment (hardening and tempering treatment) after forming is more used for springs with special requirements, such as corrosion resistance, weak magnetic, conductive and the like.