Analysis of the Ag addition on the processing and microstructure of a biomedical Ti–25Ta alloy fabricated by powder metallurgy

In this work, the effect of Ag on the sintering kinetics of a Ti–25Ta (vol.%) biomedical alloy was evaluated using dilatometry. Structural and microstructural analyses revealed the β–Ti phase stabilization due to the Ta addition, leading to localized martensitic transformation of Ti around Ta-rich regions. The addition of 7 vol.% of Ag produced a 10% increase in shrinkage during sintering, generating the Ti₂Ag precipitation through Ti-Ag eutectic reactions. The limited solubility of Ag in Ti as well as its negligible solid solubility in Ta resulted in the presence of undissolved Ag particles and intermetallic precipitates which have antibacterial potentials proper for medical device fabrication. In addition, these findings suggest that the Ti–25Ta–7Ag alloy is a promising candidate for further mechanical and biological studies to assess its suitability for biomedical applications.