| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hot dip galvanized steel sheet which is satisfactory in surface properties without any stripe patterns, and has excellent press formability. Ž<P>SOLUTION: The surface of a steel sheet having a chemical composition containing, by mass%, C, Si, Mn, P, S, sol.Al, N, sol.Ti, Nb and O in prescribed amount ranges, and in which te contents of the sol.Ti and Nb satisfy the following equations (1) to (3), and the balance Fe with impurities, and in which the content of Ti oxides in oxide inclusions is ≥50.0% expressed in terms of TiO<SB>2</SB>and the content of Nb oxides is <1.0% expressed in terms of NbO is provided with a hot dip galvanizing layer: 1.0<(Ti<SP>*</SP>/48+Nb/93)/(C/12+N<SP>*</SP>/14)(1), Ti<SP>*</SP>=max[sol.Ti-(48/14)×N, O](2) and N<SP>*</SP>max[N-(14/48)×sol.Ti, O] (3), wherein, the symbols of elements in the respective equations denote the contents of the respective elements by mass%, and max[] represents the function returning the maximum value of argument in the brackets[]. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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