MANUFACTURE OF THIN STEEL STRIP

摘要

PROBLEM TO BE SOLVED: To simplify the structure refining process of a thin steel strip manufactured with continuous casting by rolling at a specified temp. range and draft after a molten steel is rapidly cooled and solidified to produce a thin cast strip. SOLUTION: The molten steel is poured into a thin cast strip continuous casting device such as a strip caster and rapidly cooled at the rate of >=100 deg.C/s. Since the molten steel is rapidly cooled with this rapid cooling process, the thin cast strip, the solidifying structure of which is refined, is formed. Thereafter, rolling of draft >=10% to <=80% is applied at the temp. range T1 between the temp. at a transformation point Ar3 and the temp. 200 deg.C higher than the temp. at the transformation point Ar3 . The thin steel strip is completely recrystallized with this rolling process to form the refined structure. Next, the thin steel strip is cooled under the same cooling condition as a usual hot rolling process. Since the structure of the thin steel strip coiled after the treatment like this is refined, hot rolling and heat treatment or the like by reheating are not necessitated, whereby the refining process is largely simplified.