Bioinspired micro texturing of Ti-6Al-4V through micro ball-end milling for improved wettability, bio-tribological performance and bioactivity

Ti-6Al-4V titanium alloys are preferred in dental implantology and joint prostheses due to their high biocompatibility, high specific strength and corrosion resistance. However, the inherent bio-inertness of titanium alloys limits their widespread applications because implant failures frequently occur due to poor osseointegration with surrounding bone tissues. In this study, we focus on fabricating bionic textures to modify the surface and thereby enhance osseointegration between the material and bone tissue. Therefore, bioinspired micro-textures inspired by snake, fish and dung beetle scales have been fabricated in this study. The results showed that the snake-scale-inspired micro-texture with a 400 µm pitch exhibited the most promising performance in terms of roughness factor, wettability, surface energy, bio-tribology and bioactivity. This texture configuration exhibited the highest roughness factor (1.027), along with increases of 43.7% and 30.85% in wettability and surface energy, respectively. The wear performance also showed notable improvement, with the coefficient of friction reduced by 26.7% and both wear volume and specific wear rate decreasing by approximately 60.87% compared to the untextured surface. Bioinspired textured surfaces have dramatically increased hydroxyapatite precipitation by increasing the effective nucleation area. The Ca/P ratio of 1.75 obtained for the snake scale-inspired texture closely matches the stoichiometric ratio of hydroxyapatite in human bone, validating its potential to enhance osseointegration.