MAGNESIUM-ALLOY SHEET EXCELLENT IN CORROSION RESISTANCE AND SURFACE TREATABILITY, AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a magnesium-alloy sheet excellent in surface property.;SOLUTION: The magnesium-alloy sheet having excellent surface treatability is obtained by suitably subjecting a magnesium-alloy molten metal having a composition comprising, by mass, 1-11% Al, 0.1-2.0% Zn, 0.15-0.5% Mn and further, as necessary, further comprising 0.05-2% one or more kinds selected from Ca, Sr, RE, and the balance Mg with inevitable impurities in which the contents of Fe, Ni, Co and Cu are regulated to 50 ppm and the content of Cl is regulated to 20 ppm, to continuous casting, and rolling into a belt-like magnesium alloy sheet metal which is used as a substrate, and making the substrate thin by plastic working such as rolling. Further, Al-Mn compound present on the surface layer part in the sheet thickness satisfies the atomic ratio Mn/Al 1.0 and the maximum size is 10 μm, and suitably, further, the occupied area of the Al-Mn compound on the surface in the sheet thickness, is 5.0%.;COPYRIGHT: (C)2010,JPO&INPIT