Thermomechanical processing of low carbon, IF and IF high strength steels -- A few typical cases

摘要

Steel is one of the engineering materials for automobile industries. It constitutes about 60 percent of the weight of a typical car body. During last two and a half decades, the steel industry has undertaken the development and stable mass production of high performance, high quality steel sheets as demanded by the automobile industries. The principal properties of interest in steel sheets are strength, ductility, formability, and weldability. The control of final microstructure begins during solidification and proceeds during reheating, hot rolling and final transformation. Most of the steel sheets used in the autobody are in cold rolled and annealed condition in order to induce strength and desired crystallographic structure for formability. The hot band properties greatly affect the finishing properties of cold rolled annealed temper rolled steel sheets. The paper discusses a few typical cases of Low carbon, Interstitial free and Interstitial free-high strength steels, elucidating the effect of thermomechanical processing on mechanical properties.