Salt spray corrosion and electrochemical corrosion properties of anodic oxide film on 7475 aluminum alloy

An anodic oxide film was prepared in the surface of 7475 aluminum alloy by anodic oxidation, and corrosion resistance of the anodic oxide film was investigated. The corrosion influence of 7475 aluminum alloy after the anodic oxidation was discussed, and the electrochemical corrosion test was researched. The results show that the corrosion in the original sample surface is severe after salt spray corrosion, while the anodic oxide film is only slight corrosion, owing to Al2O3 prevents Cl− to contact the base metal effectively. The corrosion potential increases in the positive direction to improve its corrosion resistance after anodic oxidation.