| 摘要 |
PROBLEM TO BE SOLVED: To provide a galvannealed steel sheet excellent in sliding properties at the time of press forming, also excellent in chemical treatment characteristics and adhesiveness, and further having no press scars, and to provide a manufacturing method therefor. SOLUTION: The method for manufacturing a galvannealed steel sheet includes hot dip galvanizing a steel sheet; heating the hot dip galvanized steel sheet to alloy the coating layer; temper rolling the galvannealed steel sheet; contacting the temper-rolled steel sheet with an acidic solution, and then allowing the temper-rolled steel sheet to stand for about 1 to about 30 second(s) to form an oxide layer on the surface of the temper-rolled steel sheet, and washing the temper-rolled steel sheet, on which the oxide layer is formed, with water. The acidic solution has a pH-buffering action and contains Fe ions in which the concentration of Fe<SP>3+</SP>ions is≤2.0 g/l, and the balance Fe<SP>2+</SP>ions. The galvannealed steel sheet is manufactured by the manufacturing method. COPYRIGHT: (C)2005,JPO&NCIPI
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