| 摘要 |
PROBLEM TO BE SOLVED: To produce a cold rolled steel sheet having high formability so as to withstand complicated press forming and having less brittleness in secondary working by which brittle fracture in secondary working is not generated even after complicated press forming of high strain and suitable as a steel sheet for press forming such as an automotive steel sheet and to provide a method for producing the same. SOLUTION: This cold rold steel sheet has a composition containing, by weight, <=0.0025% C, <=0.05% Si, 0.05 to 0.25% Mn, 0.009 to 0.02% P, 0.003 to 0.02% S, 0.01 to 0.1% Sol.Al, 0.020 to 0.04% Ti, 0.021 to 0.03% Nb and 0.0025% N, and the balance substantially Fe with inevitable impurities.
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