Corrosion protection of 2024-T3 aluminium alloy by electro-polymerized 3-amino 1,2,4-triazole in sulphate solution containing chloride

Electro-oxidation of 3-amino 1,2,4-triazole (ATA) on Al 2024-T3 alloy carried out simultaneously to the anodizing process in methanol acetate or in aqueous sulphate medium, leads to the formation of Cu^I-ATA complex upon Cu-rich particles. The anodizing film grows, in both media, according to high field-assisted migration mechanism and the potential field is in the order of 10⁶ V cm⁻¹. Significant protective effect of films towards localized corrosion was observed due to Cu^I-ATA and poly(ATA) formations on Cu-rich particles. These complex layers hinder also the oxygen reduction reaction leading to a lower corrosion rate at the open circuit conditions.