Influence of seawater depth and electrode potential on the tribocorrosion of Ti6Al4V alloy under the simulated deep-sea environment by in-situ electrochemical technique

Abstract

Tribocorrosion of Ti6Al4 V alloy has been investigated in 3.5 wt.% NaCl solution under simulated deep-sea environment. The results demonstrate tribocorrosion rate increases with hydrostatic pressure (i. e. seawater depth) at an accelerated speed of 5.9×10-6 mm3·N-1·m-1·MPa-1. Wear volume under potentiostatic tribocorrosion depends on potential and experiences a maximum at -0.2 VAg/AgCl where the volume at 20 MPa is almost tripled that at 0.1 MPa. Therefore, both hydrostatic pressure and potential have significant effect on tribocorrosion behaviour. At higher hydrostatic pressure, tribocorrosion is dominated by delamination wear and the increment in wear volume results from mechanical wear and synergism.