众所周知,热卷弹簧必须经受淬火-回火后,获得了回火索氏体组织,才具备良好的综合机械性能。机车车辆弹簧按铁标规定,其热处理后的硬度为42.7～49.7H_(Rc)(新)。淬硬了的硅锰弹簧钢要达到此硬度,必须在400～480℃温度范围内进行回火处理。淬火组织(马氏体)是不稳定的,有转变到稳定状态的自然趋向,而且回火温度越高,越趋向稳定状态 As we all know, hot coil spring must be subjected to quenching - tempering, get tempered sorbite, have good overall mechanical properties. Rolling stock springs according to the iron standard, the hardness after heat treatment of 42.7 ~ 49.7H_ (Rc) (new). Hardened silicon manganese spring steel to achieve this hardness, must be tempered within the temperature range of 400 ~ 480 ℃. Quenched tissue (martensite) is unstable, there is a natural tendency to change to a steady state, and the higher the tempering temperature, the more stable towards the state