| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable energy saving and process reduction to impart excellent workability thereto and to obtain uniform characteristics therein by subjecting electric furnace molten steel contg. specified amounts of C, Si, Mn, P, S, Al, O, tramp elements, Ti and N to continuous casting into a thin slab having a specified sheet thickness, executing hot rolling under specified conditions and thereafter coiling it at a specified temp. SOLUTION: Molten steel having a compsn. contg., by weight, <=0.005% C, <=1.5% Si, <=1.5% Mn, <=0.10% P, <=0.020% S, <=0.10% Al and <=0.01% O, furthermore inevitably contg. 0.02 to 1.5% Cu and 0.02 to 2.0% Ni as tramp elements, contg. 0.01 to 0.10% Ti, in which the content of N is controlled to 0.004 to 0.009%, moreover contg. 0.001 to 0.10% Nb or 0.0001 to 0.01% B is subjected to continuous casting into a thin slab having 10 to 80 mm sheet thickness. This thin slab is subjected to hot rolling in such a manner that the starting temp. is controlled to <=1100 deg.C, the total draft to >=50%, the draft per pass to >=35% and the finishing temp. to >=600 deg.C and is coiled at <=800 deg.C.</p> |
