| 摘要 |
PROBLEM TO BE SOLVED: To provide a galvannealed steel sheet having excellent sliding characteristics at press forming. SOLUTION: In the galvannealed steel sheet, an iron-zinc alloy plating phase composed essentially ofδ1-phase, being free fromζ-phase at the surface, and having a flat zone is formed at least on one side of a steel sheet and an oxide layer of >=10 nm thickness is formed on the surface of the flat zone. In this galvannealed steel sheet, the area ratio of the flat zone at the surface of the iron-zinc alloy plating is made to 20-80%. Further, the X-ray diffraction peak ratio between theζ-phase andδ1 phase, (ζ/δ), is made to <0.2 or the area ratio of theζ-phase in the surface layer is made to <10%.
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