| 摘要 |
PROBLEM TO BE SOLVED: To realize a high strength steel sheet and a galvanized steel sheet which have excellent formability, and a production method for them on an industrial scale. SOLUTION: The high strength steel sheet and the galvanized steel sheet having excellent formability have a composition containing, by mass, 0.08 to 0.3% C, <0.2% Si, 0.8 to 2.8% Mn, <=0.03% P, <=0.03% S, 0.25 to 1.8% Al, 0.05 to 0.3% Mo and <=0.010% N, and further containing one or more metals selected from <=1.0% Cu, <=1.0% Ni and <=1.0% Cr, and the balance Fe with inevitable impurities, and have each a metallic structure containing ferrite, >=5% retained austenite, and bainite. Preferably, the mass% of Al, C, Mn and Mo satisfy a specified relational equation.
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