Abstract:The influence of adipic acid on the formation and corrosion resistance of anodic oxide film fabricated on 2024 aluminum alloy was investigated. The morphology was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The corrosion resistance was evaluated by electrochemical impedance spectroscopy (EIS). The results showed that the adipic acid was absorbed at the electrolyte/anodic layer interface during anodizing. The corrosion rate of anodic film decreased and the film thickness increased. The film was uniform and compact especially at the film/substrate interface. After sealing procedure, anodic film formed with the addition of adipic acid exhibited improved dielectric property and corrosion resistance in aggressive environment.

Key words: aluminum alloy; anodic oxidation; adipic acid; adsorption; corrosion