Growth, corrosion, and wear study of nanocomposite PEO coating in electrolyte containing nickel sulfate

Plasma electrolytic oxidation (PEO) was performed on a 1010 Aluminum alloy. To achieve the nanocomposite structure, Si3N4 nanoparticles were added into the electrolyte. In an alkaline aqueous suspension (silicate-based), the effect of adding NiSO4 on the applied voltage, microstructure, composition, wear, and corrosion resistance of PEO coatings was investigated using Scanning Electron Microscopy (SEM), elemental analysis with Energy Dispersive Spectroscopy (EDS), X-Ray Diffraction (XRD), cyclic polarization test, and pin-on-disk wear test. The results showed that adding nickel sulfate (NiSO4) and infiltration of its constituents into coatings lead to a more favored corrosion behavior. Moreover, in the case of best sample, anodic current at the highest applied potential condition during the cyclic polarization test indicated a drop within two decades. Moreover, coefficient of friction decreased almost by half.