The Influence of Sn addition on the microstructure and mechanical properties of the new -type Ti-Mo-Nb based alloys for implant material

Titanium alloys are very interesting for biomedical applications due to excellent biocompatibility, corrosion resistance, lower density, and lower young modulus compared to cobalt and stainless steel alloys. However, compared to bone, young modulus of pure titanium and Ti-6Al-4V are still relatively high and the mechanical properties are still insufficient to meet the needs of biomaterials replacing the hard tissues. In this paper, a newly Ti-Mo-Nb based alloys were designed and the effect of Sn content in Ti-6Mo-6Nb-xSn alloys (x=0,4,8 and 12 wt%) after homogenized on microstructure, hardness, and young modulus were investigated. The alloys were produced by electric vacuum arc furnace with non-consumable tungsten electrode then homogenized at 1 100 °C for 7 under controlled argon atmosphere. Optical microscope, scanning electron microscopy, x-ray diffraction hardness test and ultrasonic test were used for alloys characterization. The results showed that Ti-6Mo-6Nb-xSn has equiaxed structure and Sn addition could promote the formation of β phase. The elasticity modulus of Ti-6Mo-6Nb-xSn alloy with the addition of 12% Sn was 88 GPa, this is better since it is below the elastic modulus of Ti6Al4V implant material.