Effect of Surface Nano Structuring on Corrosion and Tribocorrosion Behavior of Ti6Al4V Alloy in Simulated Body Fluid

Effect of surface nano crystallisation of Ti6Al4V alloy obtained through ultrasonic shot peening (USP) on its degradation behavior in simulated body fluid is investigated. Optical microscopy, EBSD, micro-hardness, XRD, EIS, XPS, and tribocorrosion studies are done. Grains refined and surface hardness increased after USP that translated into improved tribocorrosion performance. Higher hardness of USP samples led to lower mass loss, lower friction coefficient, and shallower tracks in tribocorrosion tests. Larger capacitive loop in the Nyquist plots for USP samples indicate better dielectric properties of the passive film. Resistance of Ti-6Al-4V alloy to tribocorrosion is significantly enhanced after USP, which is explained based on mechanical and electrochemical properties.