Effect of niobium content on the microstructure and Young's modulus of Ti-xNb-7Zr alloys for medical implants.

New generation titanium alloys with low elastic moduli are promising materials for medical implants, particularly load-bearing orthopaedic implants. In this paper, the effect of niobium content on the microstructure and mechanical properties of new Ti alloys including Ti-23Nb-7Zr, Ti-28Nb-7Zr and Ti-33Nb-7Zr (wt%) is studied. Ti-23Nb-7Zr was found to mainly form α΄ and α″- phases, while both the Ti-28Nb-7Zr and Ti-33Nb-7Zr consisted of α″ and β-phases with an increased amount of β-phase in the alloy with 33 wt% of Nb.