| 摘要 |
PROBLEM TO BE SOLVED: To provide galvannealed steel sheets having excellent sliding characteristics at press forming. SOLUTION: The galvannealed steel sheets are: a galvannealed steel sheet which has a layer of the oxides of Fe, Zn and Al of 1 to 400 nm thickness on a flat part of a plating surface and also has, on this oxide layer, projections composed of the oxides and/or hydroxides of Fe and Zn and having 5 to 300 nm maximum height of projections or a projection layer having the above projections; and a galvannealed steel sheet which is the same as the above one and in which, from the cross-sectional view, the number of the projections is 20 to 1,000 pieces for a length of 10μm.
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