Spring steel heat treatment method, the bearings of knowledge
Heat treatment characteristics of spring steel heat treatment depends on the spring processing forming method, generally can be divided into hot forming spring and cold forming spring two broad categories: 1)
Hot forming spring of section size > 10 mm all kinds of large and complex shape spring adopt hot forming (
Such as hot rolling, hot roll)
, such as cars, tractors, train plate spring and spring.
Its simple processing route is: heating, bending or flat or round steel cutting winding to quenching medium temperature tempering, surface peening treatment, using the state organization for tempering austenite.
Shot peening strengthening surface and improve the quality of the surface of the spring, significantly improve the fatigue performance.
Spring cold forming sectional dimension of < 10 mm small spring can use cold forming (
Such as cold rolled, cold rolled)
, such as the instrument of the spiral spring, spring and spring leaf, etc.
This kind of spring for cold drawn before forming (
Isothermal quenching, quenching medium temperature tempering or lead bath after cold drawing (
Then using the cold forming process, this process will further strengthen the metal, but also produce a large internal stress and brittleness, so should be done after low temperature annealing (
Generally 200 ~ 400 ℃)