| 摘要 |
<P>PROBLEM TO BE SOLVED: To produce a hot dip galvanized steel sheet to which hot dip galvanizing or hot dip galvannealing is applied with a steel sheet containing a relatively large amount of Si as a base material at a low cost while improving wettability of the plating. Ž<P>SOLUTION: A steel sheet in which the coiling temperature of a steel strip in a hot rolling stage is controlled to 660 to 750°C, and, the steel sheet after cold rolling, having chemical components comprising 0.07 to 0.15% C, 0.9 to 1.7% Si, 1.0 to 2.0% Mn, 0.1 to 0.2% Al, 0.002 to 0.010% P, ≤0.0010% S and ≤0.010% N, and the balance Fe with impurities, is heated in an atmosphere where a combustion gas comprising H<SB>2</SB>and CH<SB>4</SB>by ≥50 vol.% in total is burnt at an air/fuel ratio of 1.05 to 1.3 in such a manner that the temperature of the steel sheet reaches ≥550°C upon oxidation, and is further heated in a hydrogen 1 to 20 vol.%-nitrogen atmosphere having a dew point of -50 to -10°C upon reduction annealing. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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