| 摘要 |
PURPOSE: To prepare a hot dip aluminum coated steel sheet which has excellent brightness holdability and corrosion resistance and is used for exhaust blanks of automobiles, household electrical appliances, etc., by providing the surfaces of the steel sheet consisting of specific components with intermetallic compd. coating layers having specific components and thickness, and further, providing the surfaces thereof with coating layers of specific components. CONSTITUTION: The steel components are composed of, by weight, <=0.1% C, <=0.1% Si, 0.0015 to 0.0060% Ni, <=0.01% Al and the balance Fe with inevitable impurities. The surfaces of such steel sheet are provided with the intermetallic compd. coating layers having an average compsn. consisting of 25 to 50% Fe, 3 to 18% Si, 0.1 to 5% Mn, 0.05 to 0.8% Cr and the balance Al and having a thickness of <=5μm. Further, the surfaces thereof are provided with coating layers consisting of 2 to 12% Si, <=1% Fe, 0.005 to 0.3% Mn, 0.002 to 0.05 Ca and the balance Al and contg. Zn and Sn in the impurities at <=1% in total. The peeling condition is evaluated by a reverse bend test. As a result, the material whose thickness is less decreased by corrosion even in severe environment is provided.
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