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Summary:A method for manufacturing a cold rolled steel sheet to be enamel-coated and to be used as raw steel sheets for enamel-coated products such as bath tubs and components of electric appliances is disclosed. The optimum contents of the alloying elements such as S, P and N are realized, thereby satisfying the enamel layer adherence, the fishscale resistance and the formability. First, there is prepared a steel composed of, in weight %, 0.004% or less of C, 0.3% or less of Mn, 0.02-0.05% of S, 0.005-0.03% of P, 0.08-0.15% of Ti, 0.004% or less of N, 0.04% or more of an excess Ti* (being defined to be Ti*=Ti-(48/32)S-(48/14)N-(48/12)C), and a balance of Fe and other unavoidable impurities so as to form an aluminum killed steel. The aluminum killed steel is reheated, and then a hot rolling is carried out, with the finish rolling temperature being above the Ar3 transformation point. Then a coiling is carried out in the normal manner, and then, a cold rolling is carried out with a reduction rate of 50-85%. A continuous annealing is carried out above the recrystallization temperature.
Bibliography:Application Number: KR19980000267