The electrochemical and tribocorrosion behavior of hybrid ceramic film-coated Ti alloys

Abstract

In this study, anodic TiO2 ceramic coating was formed on titanium alloys produced by SLM by using the anodization method. After then, hybrid ceramic coatings are produced by combining a formation of ZrO2 nanostructures in the TiO2 coating with the SILAR technique. The microstructure, wettability, electrochemical properties, and tribocorrosion behavior of anodic TiO2 and hybrid ceramic coatings were also investigated. According to XRD results, two TiO2 peaks are observed in anodic TiO2 films. After the SILAR process, the tetragonal-ZrO2, and monoclinic-ZrO2 with TiO2 peaks were obtained in the hybrid ceramic coatings. Especially, while the intensity of the TiO2 peaks decreased, the intensity of the ZrO2 peaks increased with the increase in cycle time. The surface wettability experiments indicate that the HB-80 specimen exhibits superhydrophobic behavior, and it also has the highest contact angle value among all specimens. Corrosion tests in SBF solution confirmed that hybrid ceramic films importantly increased the anticorrosion performance of anodic TiO2 film, depending on the cycle times owing to filling the pores, and the best outcomes for corrosion resistance were obtained from the HB-80 specimen owing to its superhydrophobic properties. Moreover, the results of tribocorrosion tests revealed that all hybrid ceramic films displayed higher tribocorrosion resistance than anodic TiO2 ceramic film and uncoated Ti6Al4V substrate, and the best performance was seen from the HB-80 specimen due to its decreased porosity and the direct contact area between pin and surface.