Tribocorrosion behaviour of porous anatase and rutile phases formed on surface of anodised Ti45Nb alloy

Titanium alloys are used across a wide range of sectors—from aerospace to health—because of their low density, high strength, and corrosion resistance properties. In recent years, the use of alloying elements such as niobium (Nb), tantalum (Ta), and zirconium (Zr) has still not eliminated existing wear problems, in spite of being preferred to conventional titanium alloys that are non-toxic and have better corrosion and mechanical properties. In order to overcome this problem of titanium alloys, various surface treatments are applied. This study was mainly aimed at investigating tribocorrosion properties of anatase, rutile, and anatase-rutile phases formed on the surface of Ti45Nb by anodising at different potential values. The structural and mechanical properties of these structures were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), nanoindentation, and a 3D profilometer. Tribocorrosion tests were carried out at open-circuit potential (OCP) and two different anodic in NaCl solutions. It was found that the wear volume was affected by mechanical action rather than chemical effects for all samples during tribocorrosion. It was concluded that while a surface structure including anatase is more sensitive to chemical effects, the rutile structures were shown to be more resistant to both mechanical and chemical attacks during tribocorrosion tests.