| 摘要 |
PROBLEM TO BE SOLVED: To provide a high strength galvanized steel sheet which has excellent press formability and plating adhesion, and is useful as members for automobiles, building, electricity or the like and a production method therefor. SOLUTION: The surface of a steel sheet which has a composition containing, by mass, 0.05 to 0.2% C, 0.2 to 2.0% Si, 0.2 to 2.5% Mn and 0.01 to 1.5% Al, where Si and Al satisfy 0.4 (%)<=Si+0.8Al(%)<=2.0%, which further contains one or more metals selected from Sb, Bi, Se, Be, Mg, Ca, Zr, Sc, Y, La and Ce by 0.005 to 1.0% in total and suitably contains prescribed amounts of one or more elements selected from Ni, Cu, Sn, Co, Mo, Cr, V, Ti, Nb and B, and the balance Fe with inevitable impurities, and which has a steel structure in which the volume ratio of retained austenite satisfies 2 to 20% is provided with a galvanized layer containing >=80% Zn and <=1% Al, or a galvannealed layer containing 80 to 91% Zn, 8 to 15% Fe and <=1% Al.
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