| 摘要 |
PURPOSE:To obtain a cold-rolled steel sheet having deep drawability with high production efficiency by limiting the component ratio in steel compsn. and the cubic crystal ratio of a continuous casting slab and subjecting the slab to continuous annealing after rolling. CONSTITUTION:A molten steel consisting of <=0.015wt% C, <=1.0% Si, <=1.0% Mn, <=0.100% P, 0.005-0.150% Al, <=0.010% N, <=0.100% total of 0.002-0.100% Nb, Cr, Ti respectively and 0.0005-0.0080% B according to need, and the balance Fe and unavoidable impurities is continuously cast so as to attain >=30% cubic crystal grain ratio. The cubic crystal grain ratio is controlled by using an electromagnetic stirrer, etc. Such slab is cooled to a room temp. and is hot- rolled after reheating or directly as cast. The steel plate is further cold rolled and is continuously annealed. A cold-rolled steel sheet for deep drawing ideal for application such as the outside plate, etc. of an automobile, etc. is obtd. with good productivity by the above-mentioned method. |
