A study on corrosion behavior of micro-arc oxidation coatings doped with 2-aminobenzimidazole loaded halloysite nanotubes on AZ31 magnesium alloys

Abstract Micro-Arc oxidation (MAO) coatings with actively protective functionality by incorporating 2-aminobenzimidazole (2-ABi) loaded halloysite nanotubes (HNTs) was presented. The coatings were characterized by SEM, EDX and XRD. Corrosion behavior was evaluated by EIS, PDP and salt spray test. With the SEM and EDX analysis, the existence of HNT or 2ABi-loaded HNT was confirmed. The OCP evolution, EIS complex spectra and the result of salt spray test showed the enhanced corrosion resistance of 2-ABi-HNT MAO coating owing to the self-healing effect, suggesting 2-ABi has good potential as corrosion inhibitor for Mg alloys.