| 摘要 |
PROBLEM TO BE SOLVED: To produce a high strength hot dip galvanized steel sheet and a hot dip galvannealed steel sheet free from the generation of nonplating at the time of hot dip galvanizing even in the case a high strength steel sheet in which strengthening elements such as Si and Mn and added is used as the stock and thus excellent in adhesion for plating and press workability. SOLUTION: A steel slab having a composition containing, by weight, 0.0001 to 0.30% C and also containing one or two or more kinds selected from <=3.0% Si, 0.1 to 3.0% Mn, <=2.0% Cr and <=0.10% P is subjected to hot rolling or moreover cold rolling, is thereafter heated to >=750 deg.C, is subsequently cooled, is next dipped into an alkaline hot dip salt bath, is thereafter pickled at need, is subsequently heated and reduced at >=650 deg.C in a reducing atmosphere and is then applied with hot dip galvanizing.
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