| 摘要 |
PURPOSE:To obtain a rust-preventive multiply-plated steel material having superior rust resistance by forming the lowest layer of Zn or a Zn-Fe alloy having a low Fe content on a steel material by a small extent of deposition and by forming a Zn-Fe alloy layer having a specified Fe content as an upper layer on the lowest layer by a large extent of deposition. CONSTITUTION:A steel material is plated to form a layer of Zn or a Zn-Fe alloy contg. <10wt% Fe or further contg. a third component as the lowest layer adhering to the steel base by <5g/m<2>. A Zn-Fe alloy layer contg. 10-30% Fe or further contg. a third component is then formed on the lowest layer as an upper layer by >=10g/m<2>. An Fe-Zn alloy layer contg. a third component, an Fe or Fe-base layer may be formed on the upper layer as a surface layer by <=5g/m<2>. Thus, a multiply plated steel material having superior adhesion at low temp., superior corrosion resistance and adhesion to paint is obtd.
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