The effect of hot working on mechanical properties and microstructure of biomedical Ti-Nb-Ta-Zr-O alloyThursday (09.11.2017) 09:35 - 09:55 Part of:
Ti-based alloy Ti–35.3Nb–7.3Zr–5.7Ta–0.7O (wt.%) meets biocompatibility and strength requirements for total joint endoprostheses material. However, pores and very coarse grain structure of as-cast material result in decreased fatigue performance. Die-forging and hot-rolling were used to determine optimal process for implant manufacturing. Microstructure was studied by scanning electron microscopy including EBSD, while mechanical properties was studied by tensile and fatigue tests at room temperature. Both hot working techniques resulted in enhancement of tensile strength and also ductility. It was found that microstructural refinement increases with increasing induced equivalent strain. Both die-forging and rolling are capable to improve fatigue performance to satisfactory values. Resulting hot-worked Ti–35.3Nb–7.3Zr–5.7Ta–0.7O alloy can be readily used for implant manufacturing. Compared to common Ti6Al4V alloy, it features improved strength, lower elastic modulus to avoid the stress-shielding effect and enhanced biocompatibility.