Corrosion of aluminium alloy A6061-T6 members embedded in alkaline materials

Owing to the corrosive conditions in coastal areas, aluminium alloy railings and similar structures are normally used on infrastructure works such as bridges and roads located in such areas because aluminium alloys are inherently corrosion resistant. However, to achieve rigid support, aluminium alloy members are often embedded in concrete. Consequently, the embedded parts undergo corrosion caused by the alkaline content of the cement used in the concrete. This research was carried out to study the corrosion behaviour on both the embedded and unembedded sides of aluminium alloy A6061-T6 members embedded in the concrete and also to investigate the ability of a combined coating of anodic oxide and organic film to inhibit corrosion. Additionally, the influence of scratch damage on the performance of this coating material was evaluated.