| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot dip galvannealed steel sheet which exhibits excellent sliding performance in press forming, and to provide its production method. SOLUTION: In the hot dip galvannealed steel sheet, the surface of iron-zinc alloy plating is provided with a flat part, and the surface layer of the flat part is provided with an oxide layer of a thickness of≥10 nm. The area ratio of the flat part in the surface of the iron-zinc alloy plating amounts to 20 to 80%. The iron-zinc alloy plating layer mainly consists of theδ<SB>1</SB>phase, and contains theζphase as well. When the hot dip galvannealed steel sheet is produced, a steel sheet is subjected to hot dip galvanizing, is further subjected to heating treatment so as to be alloyed, and is subjected to refining rolling. Thereafter, an oxide layer is formed on the surface layer of the plating. COPYRIGHT: (C)2005,JPO&NCIPI
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