| 摘要 |
PROBLEM TO BE SOLVED: To prevent the corrosion of a plating layer itself and the generation of red rust from the edge faces and worked part by incorporating an Mg2Si phase into an Al plating layer having a specified compsn. of Mg, Si, and the balance Al with inevitable impurities formed on the surface of a steel sheet. SOLUTION: An Al plating layer is composed of, by weight, 0.5 to 15% Mg, 2 to 15% Si, and the balance Al with inevitable impurities. Then, by making a structure in which Mg2Si is dispersed into the Al plating layer, this Mg2Si is dissolved in the using environment to form Mg protective films on the surface of the plating layer and the surface of ferrite and prevents corrosion both in the plating layer itself and the place to which ferrite is exposed. At the time of producing an Al plated steel sheet, an Al-Fe-Si alloy layer is formed on the boundary between the plating layer and ferrite, and its thickness is preferably controlled to <=5μm. Moreover, preferably, the hardness of the plating layer is controlled to 40 to 150, and its coating weight is controlled to 20 to 100 g/m2 per side.
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