Several methods to improve the service life of the spring

1) thermomechanical treatment
Thermomechanical treatment is the deformation of steel strengthening and heat treatment strengthening both together, further improve the strength and toughness of steel.Thermomechanical treatment are high, moderate in low temperatures.High temperature thermomechanical treatment is produced under the stable state of austenite deformation immediately after quenching, can also be combined with forging or hot rolled, namely thermoforming immediately after quenching.60 si2mn steel manufacturing automobile plate spring, after the high temperature thermomechanical treatment (930 ℃ + 18% hot variables, oil quenching), with 650 ℃ high temperature tempering of x 3.25 min, its strength and fatigue life have been greatly improved.
(2) spring isothermal quenching
Can be used for small diameter or hardenability enough spring isothermal quenching, which can not only reduce, but also can improve the tenacity.Best again after isothermal quenching tempering, can improve the elastic limit, tempering temperature and isothermal quenching temperature are the same.
(3) the shot blast
Shot peening treatment is currently the most widely used one method to improve the surface quality of the spring.Spring requires a higher surface quality and surface defects such as scratches, folding, oxidation decarburization tend to become spring job stress concentration and fatigue fracture source.If use small high-speed spray the surface of the spring, steel shot peening treatment, not only improve the surface quality of the spring, to improve the surface strength, make the surface in the compressive stress state, so as to improve the spring fatigue strength and life use.