Fe-Ni ALLOY SHEET HAVING EXCELLENT RUST RESISTANCE AND ITS PRODUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a 30 to 45 wt.% Fe-Ni alloy having excellent rust resistance keeping a cost low in the production and further without remarkably changing the composition, and to provide its production method. SOLUTION: In this alloy sheet, the outermost surface layer part of about 3Åin a passive film deposited on the surface of an Fe-Ni alloy sheet has a compositional ratio satisfying <=0.6 by the atomic ratio of Fe/(Fe+Ni).