The influence of SiO2 and Al2O3 nanoparticles on corrosion resistance enhancement of Ni–P on magnesium

Abstract

In this study, the influence of adding SiO₂ and Al₂O₃ to Ni–P coated on magnesium substrate and the related corrosion resistance behavior were evaluated. The surface morphology of Ni–P–SiO₂–Al₂O₃ composite coating was investigated by field emission scanning electron microscopy (FESEM). The amount of Al₂O₃ and SiO₂ in the coating was measured by energy dispersive analysis of X-ray (EDX) and the corrosion behavior of coating was monitored by electrochemical impedance spectroscopy (EIS) and polarization techniques, showing the corrosion resistance of Ni–P–SiO₂–Al₂O₃ increases compare to Ni–P–SiO₂ and Ni–P–Al₂O₃. Furthermore, the microhardness of the coating was examined and the final hardness of Ni–P–SiO₂–Al₂O₃ reached 461 VH.