| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-strength cold-rolled steel sheet which has high stretch flange formability while securing excellent hydrogen embrittlement resistance. Ž<P>SOLUTION: Disclosed is the high-strength cold-rolled steel sheet excellent in hydrogen embrittlement resistance and workability, which has a componential composition comprising, by mass, 0.05 to 0.30% C, ≤2.0% (including 0%) Si, 0.1 to 2.8% Mn, ≤0.1% P, ≤0.005% S, ≤0.01% N, 0.01 to 1.00% Al and 0.001 to 1.00% V, and the balance iron with inevitable impurities, and has a structure comprising tempered bainite of ≥50% (including 100%) by area ratio, and the balance ferrite, wherein regarding the distribution state of precipitates in the tempered bainite, the number of precipitates with a circle equivalent diameter of 1 to 10 nm is ≥20 pieces per μm<SP>2</SP>of the tempered bainite, and the number of precipitates comprising V with a circle equivalent diameter of ≥20 nm is ≤10 pieces per μm<SP>2</SP>of the tempered bainite. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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