Biotribocorrosion of 3D-Printed silica-coated Ti6Al4V for load-bearing implants.

Laser-based 3D Printing was utilized to deposit a silica (SiO2) coating on the surface of Ti6Al4V (Ti64) alloy for implementation onto articulating surfaces of load-bearing implants. The surface laser melting (SLM) technique was implemented in 1, and 2 laser passes (1LP and 2LP) after SiO2 deposition to understand the influence of remelting on the coating's hardness and tribological performance. It was observed that compositional and microstructural features increased the cross-sectional hardness. Wear rate was observed to decrease from 2.9×10-4 in the Ti64 to 5.2 ×10-6, 3.8×10-6, and 2.1×10-7 mm3/Nm for the as-processed or zero laser-pass (0LP), 1LP, and 2LP, respectively. Coated samples displayed a positive shift in open-circuit potential (OCP) during linear wear by displaying a 368, 85, and 613 mV increase compared to Ti64 for 0LP, 1LP, and 2LP, respectively. Our results showed promising tribological performance of SiO2 coated Ti6Al4V for articulating surfaces of load-bearing implants.