from the conferences organized by TANGER Ltd.
Beta titanium alloy, Ti-35Nb-6Ta-7Zr-0.7O (wt.%), differs from most of Ti-Nb-Zr-Ta based biomedical alloys by its very high oxygen content, which provides a significant interstitial solution strengthening. However, there is a need for thermomechanical processing due to the poor fatigue resistance after casting. This is caused by a residual porosity in the ingot and large grains (size > 1 mm). Die forging was used to work the cast rod with diameter of 45 mm into rods with diameters of 35 mm and 25 mm. Resulting microstructure and mechanical properties are evaluated and discussed. Heavily deformed microstructure with deformation bands is found in the 35 mm rod without apparent grain refinement. Further forging to 25 mm leads to recrystallization and significant refinement of grain size. Porosity observed in cast condition is removed by thermomechanical processing. Yield and tensile strength are improved while the fatigue performance remains low.
Keywords: Beta titanium, biocompatibility, die-forging, tensile testing, fatigue testing© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.