Investigation of Ti-Based Alloy Composites Produced by High Pressure Torsion

This study focuses on the properties of titanium-based composite produced via high-pressure torsion (HPT) of two sandwiched disks of Ti93.4Ag2.95Pd2.95N0.7 (TiAgPdN) and Ti72.18Nb20.11Ta4.46Zr3.25 (TiNbTaZr) alloys. Both alloys in as cast state although exhibit high mechanical strength and good biocompatibility relevant to production of bioimplants might appear better in composite form. After 10 rotations in a Bridgman chamber, the microhardness of the TiAgPdN and TiNbTaZr sides of the composite increased by about 6 and 20%, in comparison with not HPT-treated samples. At the same time, for both sides, the dislocation density of about 1015 m−2 was reached already after one rotation and not significantly increased further. However, only more than three rotations were sufficient to fully glue the disks together and form an intermediate zone containing elements from both alloys. Interestingly, only the TiNbTaZr side surface became porous after etching which resulted in the best cell survival rates in comparison TiAgPdN side show cell proliferation was worse than without HPT treatment. We believe that further tuning composites parameters have promising potential for application as biomedical material.