Effect of incorporation of nanoparticles with different composition on wear and corrosion behavior of ceramic coatings developed on pure titanium by micro arc oxidation

Abstract

The aim of this work is to find a simple mechanism to explain how incorporation of nanoparticles into the prepared ceramic coatings on titanium by micro arc oxidation (MAO) technique can affect the corrosion and wear behavior of MAO coatings. In order to attain this purpose, SiC, Al2O3 and TiO2 nanoparticles were added to aluminate based electrolytes and composite MAO coatings were prepared under constant voltage regime using a pulsed power supply and their corrosion and wear properties were compared with a base MAO sample. Furthermore, the effect of addition of nanoparticles on the surface morphology, thickness and chemical and phase composition of the obtained coatings were examined. The results showed that incorporation of nanoparticles (7.5gL−1) into the coatings had no effect on the current-time responses and coating thickness of the samples, despite the nanoparticles had filled the surface micropores and cracks. However, addition of nanoparticles reduced the corrosion current density, surface roughness, friction coefficient and wear rate and increased the corrosion resistance and hardness of the coatings. Consequently, it was concluded that incorporation of nanoparticles improved the anticorrosion and wear properties of the MAO coatings. In addition, the inclusion of TiO2 nanoparticles in the MAO coating showed the best anticorrosion and wear performance among all the other composite coatings under investigation.