Microstructure, mechanical behavior and biocompatibility of powder metallurgy Nb-Ti-Ta alloys as biomedical material

•Nb-25Ti-xTa (x = 10, 15, 20, 25, 35 at.%) alloys were fabricated by powder metallurgy.•The content of Ta and the sintering temperature would adjust the phase composition.•Nb-Ti-Ta alloys have the potential to induce apatite in vitro and a high biocompatibility.•Nb-Ti-Ta alloys are quite promising as a new candidate of biomedical application.

Microstructures, mechanical properties, apatite-forming ability and in vitro experiments were studied for Nb-25Ti-xTa (x = 10, 15, 20, 25, 35 at.%) alloys fabricated by powder metallurgy. It is confirmed that the alloys could achieve a relative density over 80%. Meanwhile, the increase in Ta content enhances the tensile strength, elastic modulus and hardness of the as-sintered alloys. When increasing the sintering temperatures, the microstructure became more homogeneous for β phase, resulting in a decrease in the modulus and strength. Moreover, the alloys showed a good biocompatibility due to the absence of cytotoxic elements, and were suitable for apatite formation and cell adhesion. In conclusion, Nb-25Ti-xTa alloys are potentially useful in biomedical applications with their mechanical and biological properties being evaluated in this work.