Corrosion inhibitors for anodised aluminium

•Corrosion inhibitors are used to impart anti corrosion activity to anodised aluminium.•Inhibitors chelate copper in anodic oxide increasing the corrosion resistance.•Corrosion resistance increased with the inclusion of tetrazine molecules.•Inhibitor soaked with hydrothermal seal significantly increases corrosion resistance.

A novel sealing process for anodised aluminium has been developed based on inclusion of environmentally compliant corrosion inhibitors. Nanoporous oxide films formed by sulphuric acid anodising on aerospace grade AA2024-T3 have been sealed with a combination of corrosion inhibitors and surface hydration. The corrosion resistance was evaluated using electrochemical impedance spectroscopy and accelerated corrosion testing in a neutral salt spray environment. The synergistic anti-corrosion mechanism of the inhibitors within the oxide film on the corrosion prone alloy was determined. The technique described offers numerous opportunities for industrial applications.