Discoloration of Anodized AA6063 Aluminum Alloy

The effect of the anodizing process parameters and the influence of beta'(Mg2Si) phase on the appearance of the anodized AA6063 aluminum alloy have been investigated. It was found that beta'(Mg2Si) phase was preferentially oxidized at low anodizing voltages and the selective oxidation of beta'(Mg2Si) phase resulted in the development of a rough alloy/film interface and the incorporation of silicon into the porous anodic film, which led to the discoloration of the anodized alloy. (C) The Author(s) 2014. Published by ECS. All rights reserved.