| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot dip galvannealed steel sheet maintaining good slidability at the time of press working, in which powdering and flaking are hard to be generated and excellent in press formability. SOLUTION: This steel sheet is the one having a compsn. contg. 0.2 to 0.6% Al, 8 to 15% Fe and one or more kinds among Pb, Bi, Cd and Sn by 0.03 to 0.2% in total and having a micro-depressed part 10 in which the plating thickness is regulated to <50% of the average value H of the plating thickness, by 1 to 10% based on the cross-sectional length ratio. Furthermore, the surface roughness of the plating film is regulated to the center line average roughnes of <=1.2μm. As for the method for producing the steel sheet, hot dip galvanizing is executed by using a plating bath contg. 0.13 to 0.4% Al and one or more kinds among Pb, Bi, Cd and Sn by 0.03 to 0.2% in total, and allaying treatment is executed.
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