| 摘要 |
PURPOSE:To obtain a steel sheet excellent in chemical convertibility, secondary paint adhesiveness, etc., by constituting the coating layer of a multilayer coated steel sheet with the coating layers of an Fe-Zn alloy, an Fe-Ni-Zn alloy and then Zn sequentially from the surface layer. CONSTITUTION:In a multilayer coated steel sheet having three or more coating layers on at least one side, its surface layer comprising the electroplating layer of an Fe-Zn alloy containing 5-25wt% Zn is let optionally contain 3-30mg/m<2> Sn. An inner layer just under said surface layer is the electroplating layer of an Fe-Ni-Zn alloy containing 10-50wt% Fe and 8-18wt% Ni, and the layer further just thereunder is a corrosion preventive Zn or Zn alloy layer. Hence, the multilayer coated steel sheet excellent in workability, weldability and red rust resistance is obtained.
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