Morphology, microstructure and tribological properties of anodic films formed on Ti10V2Fe3Al alloy in different electrolytes

This study investigated the morphology, structure and tribological properties of the three samples produced by anodic oxidation of Ti10V2Fe3Al in a sulfuric/phosphoric acid electrolyte (SPA), a near-neutral sodium tartrate electrolyte without nanoparticles (STA) and a near-neutral sodium tartrate electrolyte with polytetrafluoroethylene (PTFE) nanoparticles (CA) in suspension. The STA film had a surface full of bulges and cracks, the SPA film was porous, and the CA film was nanoporous. The SPA film was mainly composed of anatase TiO2, whereas the STA and CA films were mainly amorphous TiO2 with little anatase. The tribological tests indicated that the SPA sample had a lower wear resistance than the titanium alloy substrate, which was attributed to the shedding of abrasive debris, leading to rapid wear. Both STA and CA samples exhibited much lower wear rates than the titanium alloy substrate, and CA sample displayed the lowest wear rate attributed to the formation of a lubricating layer by PTFE nanoparticles. The wear mechanisms are proposed.