Bio-corrosion behaviour of oxygen diffusion layer on Ti-6Al-4V during tribocorrosion

Oxygen diffusion layers (ODL) on Ti-6Al-4V were produced by thermal oxidation at a temperature of 850 °C for three and six hours. ODL formation resulted in a β-Ti to α-Ti transformation, causing an increase in hardness. Polarization and EIS studies in stagnant and tribocorrosion conditions were performed under normal loads of 3–30 N in a phosphate buffered saline solution. In a stagnant condition, a passive bilayer film was formed on samples, which led to a low icorr. During tribocorrosion, the formation of a protective tribofilm resulted in a higher Ecorr and a lower icorr in ODLs compared with Ti-6Al-4V.