Stability of benzotriazole-based films against AA2024 aluminium alloy corrosion process in neutral chloride electrolyte

The inhibitive effect brought by benzotriazole (BT) on AA2024 in neutral aerated sodium chloride solutions was evaluated using electrochemical techniques (large and micro scale polarization curves, electrochemical impedance spectroscopy) and surface analyses (ToF-SIMS and XPS) in the view of its incorporation into protective coatings to provide self-healing ability. It was found that the formation of a benzotriazole-based film concerns the entire surface, covering the aluminium matrix and the intermetallic particles. The presence of inhibitor in the electrolyte is required to preserve the inhibitive layerstability. The film formation is favoured by the presence of chloride ions in the inhibitor-containing solution.