Effect of Thermo-Mechanical Treatment On Superelastic Behavior of Ti-19Nb-9Zr-1Mo (at. %) Alloy

The effect of thermo-mechanical treatment on superelastic behavior of arc melted Ti-19Nb-9Zr-1Mo (at. %) alloy is investigated. The cold rolled alloys are heat-treated at 600^oC for 30 minutes followed by ice water quenching. Both reverse and forward martensitic transformation peaks are identified using the differential scanning calorimetry (DSC) thermal analysis. Cyclic tensile test was used to measure the shape memory and superelastic behaviours of the alloy. The strains of the annealed alloy are almost completely recovered by heating, starting from the 2^nd cycle due to the reverse martensitic transformation. Superelastic strain of about 4% is obtained in the annealed alloy. It is suggested that this superelasticity is due to the local barrier of nano-domains. The Young’s modulus of the heat treated alloy after cyclic training is approximately of 30GPa, which is close to that of cortical bone of human beings (7-35GPa). This superelastic and low Young’s modulus Ti19Nb9Zr1Mo alloy is a potential candidate for biomedical applications.