ELASTIC MODULUS, MICROPLASTIC PROPERTIES AND DURABILITY OF TITANIUM ALLOYS FOR BIOMEDICAL APPLICATIONS

This research was focused on a new low-modulus beta-type titanium alloy Ti-26Nb-7Mo-12Zr (wt.%). The microstructure effects on elastic modulus (measured by the acoustic resonance method) as well as microplastic, mechanical, tribological, and corrosive properties of Ti-26Nb-7Mo-12Zr alloy after thermomechanical processing were examined. The microstructure was characterized in detail by scanning electron microscopy and electron backscatter diffraction methods. The experimental research results have shown that formation of the fully recrystallized structure in the titanium alloy leads to an increase in elastic modulus, microplastic flow stress and plasticity, as compared to the corresponding characteristics of the alloy having partially recrystallized and coarse-grained structures. The durability of beta titanium alloy was examined and compared with that of commercially pure alpha titanium (CP Ti). It was found that, in the same creep loading conditions, the low-modulus Ti-26Nb-7Mo-12Zr alloy exhibits a longer time to creep fracture, as compared to the pure alpha titanium.