Effect of Nb content on microstructure and mechanical properties of porous Ti-Nb alloys

Porous Ti-Nb alloys with different contents of Nb elements were prepared by vacuum sintering technology. The effects of Nb element contents on pore morphologies， porosities， microstructures， elastic modulus， and wear resistances of porous Ti-Nb alloys were investigated. The results show that with the ascent of Nb element contents， the pore morphology of porous Ti-Nb alloys does not change significantly， and the porosities increase gradually. The porous Ti-Nb alloys are mainly composed of α-phase and β-phase， in which， due to the β-phase stabilizing effect of Nb elements， the volume fraction of the β-phase in the alloys increases significantly with the increase of the Nb element content， and the compressive strength and elastic modulus of the alloys decrease gradually. The wear resistance of porous Ti-Nb alloys in simulated body fluid （SBF） is mainly related to the volume ratio of β-phase to α-phase. When the volume ratio of β-phase to α-phase exceeds 61.7/38.3， the wear resistance of the alloy gradually improves.