Plasma Electrolytic Oxidation Coatings Enhanced by Cerate and Boride Compounds on Ti6Al4V Alloy

The PEO (plasma electrolytic oxidation) coatings enhanced by cerate and boride compounds on Ti6Al4V alloy are investigated in this paper. The PEO process is carried out with different current densities in borate-based and cerate-based electrolytes. The morphology, microstructure, and phase of the layers enhanced by the cerate and boride compounds are analyzed contrastively. It is indicated that the PEO coatings enhanced by the cerate and boride compounds are composed of the oxide layer, diffusion layer, and transition layer. The oxide layer mainly contains TiO, TiO2, Ce2O3 and CeO2 phase, the diffusion layer mainly contains TiB2, and the transition layer contains TiB and substrate phase. At high temperatures, the wear types of the PEO coatings enhanced by the cerate and boride compounds are mainly abrasive wear, adhesive wear, and accompanied by oxidation wear, while the PEO coatings enhanced by the boride compounds to have higher wear resistance at 300 degrees C and below 500 degrees C.