| 摘要 |
A method for manufacturing an iron-zinc alloy plated steel sheet having two plating layers and excellent in electropaintability and press-formability, which comprises the steps of: passing a steel sheet through a zinc dip-plating bath to form a zinc dip-plating layer on at least one surface of the steel sheet; then, heating the steel sheet, on which the zinc dip-plating layer has been formed, to alloy the zinc dip-plating layer and the surface portion of the steel sheet, so as to form, on the surface thereof, an alloying-treated iron-zinc alloy dip-plating layer as a lower layer having a plating weight of from 30 to 120 g/m2 per surface of the steel sheet; then, passing the steel sheet through an acidic plating bath for 1 to 5 seconds without electrifying same to dissolve the surface portion of the alloying-treated iron-zinc alloy dipplating layer, so as to form numerous fine jogs on the surface thereof; and then, electroplating the steel sheet in an iron alloy acidic electroplating bath to form an iron alloy electroplating layer as an upper layer, having a plating weight of 1 to 10 g/m2 per surface of the steel sheet, on the alloying-treated iron-zinc alloy dip-plating layer as the lower layer having the numerous fine jogs.
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