Wear behaviour of titanium based composites reinforced with niobium pentoxide in saline and acidic environments

The present study reports on the wet wear behaviour of spark plasma sintered commercial pure titanium (Cp Ti) and Ti-based composites containing 5, 10, and 15 wt% Nb₂O₅ in acidic and saline environments. The wear properties in wet (3.5 wt% NaCl and 0.3 M H₂SO₄ solutions) environments were assessed using a tribometer. The wear volumes and wear rates, irrespective of the environment, decreased with an increase in the Nb2O5 wt.%, which was linked to the harder Nb₂O₅ particles. Furthermore, the wear rate was relatively higher in the acidic environment than in the saline environment. This was connected to the higher chemical attack likely in the acidic environment due to the aggressive nature of the SO₄⁻ ions compared to the less aggressive 3.5 wt% NaCl solution. Abrasive wear prevalence, combined with chemical attack-induced particle scratch-off and subdued adhesive wearing, were mechanisms acknowledged to be operational for wet environments.