抄録
The strength of microalloyed medium carbon steels is significantly affected by chemical compositions and the conditions in hot forging. The effect of chemical compositions on the hardness of medium carbon steels is first investigated and is introduced as “Hardness Equivalent Parameter”, Heq. by the authors. According to this parameter, it becomes possible to design the steel for automobile components with various strengths. The effect of hot working conditions on the hardness of the microalloyed steels is examined and the proper processing conditions for them has been obtained.
After research programs have been conducted, the running test of engine and suspension components built-in a passenger car are carried out, and the authors have certified that the microalloyed steels possess satisfactory properties as forged.
