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

Abstract

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