A new technology to improve R_m-value of extra low-carbon and high strength sheet steel

摘要

Since 1980's, extra low-cargbon and high strength sheet steel has bene widely used for manufacturing outer covering pawrts of car because of its superior depe drawability and high strength. But compared with IF steel, to add phosphorus into this steel for ensuringhigh strength makes r_m-vlaue decrease, so that its applications are definitely limited. To improve r_m-value further, the authors invented a new process. R_m-value of the finished sheet steel obtained through this technology is as high as 2.85 and its {111} texture remarkably strengthens. And the research results of this paper show thata nucleus of the new technology is not only supplying a good cold rolled parent state which benefits to develop strong {111} annealing texture through the texture pretreating, but providing a favorable environment for the continuous development of the texture by the texture retreating.