| 摘要 |
PROBLEM TO BE SOLVED: To inexpensively provide a surface treated steel sheet excellent in appearance, workability and weather resistance as a steel sheet excellent in the color tone of the appearance, excellent in weather resistance in an atmospheric environment and a wet-dry repeated atmosphere and capable of withstanding severe press forming. SOLUTION: The surface of a steel sheet is provided with a galvanizing layer of 20 to 500 g/m2 coating weight as a primary plating layer, the surface of the primary plating layer is provided with an Ni plating layer of 1 to 100 g/m2 coating weight as a secondary plating layer, and, moreover, a chromate treated film of 5 to 70 mg/m2 coating weight as the content of metallic Cr. Or, the eluting quantity of sexivalent chromium in the chromate layer is controlled to <=1 mg/m2 or, in the steel, B is contained by 0.0003 to 0.0040%.
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