| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a hot-dip galvannealed steel sheet having excellent adhesiveness and lubricity, and its manufacturing method, and zinc phosphate treatment liquid. Ž<P>SOLUTION: The manufacturing method of the hot-dip galvannealed steel sheet comprises a surface controlling step, a zinc phosphate treatment step for bringing zinc phosphate treatment liquid into contact with a surface of a surface-controlled hot-dip galvannealed steel sheet, and a drying step of drying the surface of the hot-dip galvannealed steel sheet. The zinc phosphate treatment liquid contains phosphoric acid radical of ≥20g/L and ≤70g/L in terms of PO<SB>4</SB>, fluorinated acid radical of ≥0.9g/L and ≤5g/L while the acid ratio being ≥2.5 and ≤6.5. In the hot-dip galvannealed steel sheet, a zinc phosphate film contains P of ≥10 mg/m<SP>2</SP>and ≤300 mg/m<SP>2</SP>while the soluble zinc phosphate ratio being <50%. The zinc phosphate treatment liquid contains phosphoric acid radical of ≥20g/L and ≤70g/L in terms of PO<SB>4</SB>, and fluorinated acid radical of ≥0.9g/L and ≤5g/L while the acid ratio being ≥2.5 and ≤6.5. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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