| 摘要 |
PURPOSE:To economically manufacture an aluminum killed cold rolled steel plate which is excellent in its deep drawing property, by continuously hot-rolling an aluminum killed steel hot casting piece of a specified composition without executing reheating, winding it, and subsequently heating and annealing at a high speed after cold rolling. CONSTITUTION:As to an aluminum killed steel hot casting piece consisting of <=0.15% C, <=0.5% Mn, 0.015-0.100% Al, 0.003-0.008% N, and Fe and inevitable impurities as remains, which has been manufactured by a continuous casting machine, continuous rolling is started at >=900 deg.C surface temperature without executing reheating, finish rolling is executed within a range of under an Ar3 point and the Ar3 point -100 deg.C, said piece is wound at <=600 deg.C, and after that, or regular cold rolling is performed as it is, and after that, annealing is executed at a heating speed of >=20 deg.C/hr, by which a heating speed in case of annealing can be increased without cooling and reheating the hot casting piece, and by precipitating fine AlN at the stage of finish rolling, and an aluminum killed cold rolled steel plate is obtained economically and with high productivity. |
