Microstructure and mechanical properties of spark plasma sintered Ti-Mo alloys for dental applications

Ti-Mo alloys with various Mo contents from 6wt% to 14wt% were processed by spark plasma sintering based on elemental powders. The influence of sintering temperature and Mo content on the microstructure and mechanical properties of the resulting alloys were investigated. For each Mo concentration, the optimum sintering temperature was determined, resulting in a fully dense and uniform microstructure of the alloy. The optimized sintering temperature gradually increases in the range of 1100-1300A degrees C with the increase in Mo content. The microstructure of the Ti-(6-12)Mo alloy consists of acicular alpha phase surrounded by equiaxed grains of beta phase, while the Ti-14Mo alloy only contains single beta phase. A small amount of fine alpha lath precipitated from beta phase contributes to the improvement in strength and hardness of the alloys. Under the sintering condition at 1250A degrees C, the Ti-12Mo alloy is found to possess superior mechanical properties with the Vickers hardness of Hv 472, the compressive yield strength of 2182 MPa, the compression rate of 32.7%, and the elastic modulus of 72.1 GPa. These results demonstrate that Ti-Mo alloys fabricated via spark plasma sintering are indeed a perspective candidate alloy for dental applications.