| 摘要 |
PROBLEM TO BE SOLVED: To produce a cold rolled steel sheet excellent in surface roughing resistance and ridging resistance as well as in deep drawability. SOLUTION: The cold rolled steel sheet has a composition consisting of, by weight, <=0.01% C, <=2.0% Si, <=3.0% Mn, <=0.15% P, 0.01-0.20% Al, <=0.01% N, and the balance Fe with inevitable impurities. Further, in this steel sheet, the cross-sectional area ratio and average diameter of the 100} orientation colony satisfy the following inequalities I and II; I: f/D>=0.0005, and II: (2.8-r)/250<=f/D<=(4.0-r)/250. In the inequalities, (f) means the cross-sectional area ratio of the 100} orientation colony, D means the average diameter (μm) of the 100} orientation colony, and (r) means average r-value (where r<=1.5 is satisfied).
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