Study on the performance of ceramic coatings via micro-arc oxidation with doping CNTs

Abstract:

The composite ceramic coatings with excellent performance was prepared by micro-arc oxidation with doping CNTs. Influence of CNTs doping method on microstructure, phase composition, wear resistance, corrosion resistance, porosity and pore uniformity were investigated. The results show that the decrease of length to diameter ratio, the change from super hydrophobicity to hydrophobicity and the introduction of oxygen-containing functional groups after modified, increased the dispersion of CNTs in solvents. The addition of CNTs made the coatings smoother and more dense. The coatings were composed of rutile TiO2, anatase TiO2 and CNTs. The addition of CNTs helped to improve the wear resistance and corrosion resistance of coatings. The A-CNTs/MAO coating was not completely damaged after friction test for 20 minutes, showing the best wear resistance. The self-corrosion potential of A-CNTs/MAO coating was -67.61mV, the corrosion current density was 7.43×10-7 A?cm2, and the polarization resistance was 6.84×104 Ω?cm2, showing the best corrosion resistance.

Key words:Pure Ti; micro arc oxidation(MAO); doping method of CNTs; wear; corrsion