Study on the Effect of Applying Benzimidazole–Ethanol Solution as a Film–Forming Corrosion Inhibitor on the Surface of Aluminium Alloy 2024-T3

The Al-Cu-Mg light alloys’ storage characteristics are such that their use for building structures, marine offshore applications, and aeroplane components, with excellent strength/weight ratios, would not be possible without adherent anticorrosion preservation. Many techniques and strategies are still being used to treat the surfaces, such as cladding, anodising, and greasing. However, due to their costly and time-consuming nature, these techniques are considered complicated. Therefore, volatile organic inhibitor components are now being used effectively. Benzimidazole (BZI) and its derivatives are one of these film-forming chemicals used on copper and steel, directly or as injectables, combined with other carriers, such as fatty acids or dissolvable hydrocarbons, with highly efficient corrosion protection. Therefore, this paper will investigate the enhancement of the corrosion protection afforded by direct spraying of BZI solution on the surface of aluminium alloy AA 2024-T3 The corrosion protection performance results from the high electronegativity of BZI as a film-forming inhibitor, which will be adsorbed on the metallic surface, as it may emulate active protection. The corrosion protection properties of the BZI film-forming coating were preliminarily studied with 3.5% NaCl by using electrochemical impedance testing and simulations. The surface chemical adsorption confirmation was carried out by infrared spectroscopy (ATR-FTIR), supported by analysing the morphology of the surface before and after the immersion testing by using scanning electron microscopy (SEM) real-time imaging within one week of immersion. The benzimidazole film-forming coating exhibited good anticorrosion properties, providing an adherent protection film on AA 2024-T3 samples comparing with bare cladded AA 2024-T3, with a cost-effective and easy application process