The micro- and macro-tribological behaviors of a novel hierarchical TaN/Ta coating deposited on Ti6Al4V biomedical alloy by direct current magnetron sputtering were analyzed in the present work. This analysis was associated with the morphological, structural, and mechanical properties, as well as the roughness changes during and after the tribological tests. The wear track of the coating after the macro-tribology tests was evaluated by Raman spectroscopy in order to detect the compounds formed as a result of the tribo-reactions that occurred during the tests. Micro- and macro-tribology behaviors showed a significant wear rate reduction of the hierarchical coating in comparison to the Ti6Al4V substrate. For the case of the micro-tribology tests, this reduction was attributed to the high hardness of the coating (31.4 GPa); however, this hardness caused a considerable increment in the friction coefficient. On the other hand, the macro-tribology performance was associated with the hardness and the ability of the hierarchical architecture to prevent the propagation of cracks. Moreover, the friction coefficient increased considerably at the end of the test; this increment was associated with the tantalum oxides in the wear track detected by Raman spectroscopy.

The microstructure, elastoplastic properties, and corrosive response of induced porous Ti-TiH₂ materials reinforced with TiB₂ particles were investigated. Samples were fabricated using CP-Ti Grade1, Titanium Hydride (TiH₂), TiB₂ powders (0, 3, 10, and 30 vol.%), and ammonium bicarbonate salt (40 vol.%) as a space holder. Composites were fabricated using the Powder Metallurgy technique under high-vacuum conditions (HVS) at 1100 °C. Scanning electron microscopy, X-ray diffraction, nanoindentation tests, and electrochemical assays were used to investigate the pore formation, pore distribution, phase formation, elastoplastic properties, and electrochemical behavior of the compounds, respectively. With a mean pore diameter of 50–900 µm and Young’s modulus of less than 100 GPa, which is close to the properties of human bone, the pore structures of the compounds processed here are shown to be a potential biomaterial for osseointegration. In addition, their $H/E_r$ and $H^3/{E_r}^2$ ratios for the reinforced samples are higher than those of the unreinforced sample (1.5 and 4 times higher than the unreinforced sample, respectively), suggesting a better wear resistance of the Ti-TiH₂/xTiB₂ composites. Electrochemical experiments demonstrated that the Ti-TiH₂/xTiB₂ composites exhibited superior passivation properties compared to the Ti-TiH₂ sample. Additionally, the corrosion rates exhibited by the 3 and 10 vol.% of TiB₂ samples were found to be within an acceptable range for potential biomedical applications (29.26 and 185.82 E-3 mm·y⁻¹). The elastoplastic properties combined with the electrochemical behavior place the Ti-TiH₂/3-10TiB₂ composites as potential candidates for the biomedical application of CP-Ti.