METHOD FOR PRODUCING COLD ROLLED STEEL SHEETS WITH LOW CARBON WHILE HAVING EXCELLENT PROCESS ABILITY

摘要

PURPOSE: A method for producing cold rolled steel sheets is provided to have excellent processability with a r-bar value of 1.1 by using low carbon steel. CONSTITUTION: A steel slab is composed of 0.03-0.05wt% of C, under 0.20wt% of Si, under 0.30wt% of Mn, under 0.02wt% of P, under 0.02wt% of S, 0.10-0.20wt% of Cu, and the remnant wt% of Fe and impurities. The steel slab is hot rolled for being wound up at a temperature of 650-710°C. Then, the steel slab is cold rolled and annealed for having excellent workability with low carbon.