Development of a low elastic modulus and antibacterial Ti-13Nb-13Zr-5Cu titanium alloy by microstructure controlling

In order to prepare a titanium with a low elastic modulus and good antibacterial property to meet the requirements as a biomedical material, Ti-13Nb-13Zr-5Cu (TNZ-5Cu) alloy was prepared by high vacuum consume electric arc melting furnace and then subjected to a solution treatment at 950 °C followed by a short-term aging treatment at 600 °C, for 15 min, 30 min, 1 h and 2 h, respectively. The microstructure, mechanical property, antibacterial property and biocompatibility of TNZ-5Cu were investigated in detail. The research results have shown that the solid solution treated alloy was mainly composed of β-phase and α″-phase, while the aged alloys of β-phase, α″-phase, α-phase and Ti₂Cu. Compared with Ti-13Nb-13Zr alloy (65 GPa) and Ti-6Al-4 V alloy (111 GPa), the elastic modulus of TNZ-5Cu alloy after solution treatment was about 72 GPa and increased with the aging treatment up to 85 GPa, and the hardness was maintained at a higher level than that of Ti-13Nb-13Zr alloys (288 HV). The bacteria plate count results showed that the antibacterial ability of TNZ-5Cu alloy increased with the extension of the aging duration from <60% at 15–30 min to >90% at 1–2 h. Cell experiments showed that all TNZ-5Cu alloy had good cell compatibility. The low modulus and the antibacterial property could provide potential to avoid stress shield and device-related inflection in the clinical application.