Improved mechanical and wear properties of Ti−35Nb−5Ta−7Zr− x Si alloys fabricated by selective electron beam melting for biomedical application

As the next generation biomedical titanium alloy, β -type titanium alloys are excellent candidates for biomedical applications due to the relative low elastic modulus and the contained non-toxic elements. However, the relative low strength and unsatisfactory tribological property are undesired for load-bearing implant applications. In this study, 0–5 at% Si was added to the classic Ti−35Nb−5Ta−7Zr alloy to improve its strength and wear resistance, and the (Ti−35Nb−5Ta−7Zr) 1− x −Si x ( x =0, 1 at% and 5 at%) alloy were fabricated by selective electron beam melting (SEBM) technology. The results indicated that Si addition significantly increases in compressive yield strength, which is mainly due to grain refinement strengthening. At the same time, the wear rate of the as-built TNTZ-5Si alloy in SBF solution was only ∼30% of the Ti−6Al−4V alloy. Consequently, the TNTZ-5Si alloy showed an excellent combination of compressive yield strength, elastic modulus and wear resistance for potential load-bearing implant applications.