AL alloy member having excellent corrosion resistance

摘要

An Al alloy member having excellent corrosion resistance comprises an Al or Al alloy substrate having an anodic oxide film including a porous layer and a pore-free barrier layer. At least a part of a structure of the barrier layer is altered into boehmite and/or pseudo-boehmite, a dissolution rate of the film is at 100 mg/dm<2>/15 minutes or below when determined by an immersion test in phosphoric acid/chromic acid (JIS H 8683-2), and a corroded area percent is at 10% or below after allowing the film to stand in an atmosphere of 5% Cl2-Ar gas at 400° C. for 4 hours.