Microstructural Evolution and Biocompatibility of Porous and Low-Cost Ti–MO and Ti–Mo–Fe Alloys

This work investigated the enhancement of mechanical properties and anticorrosion resistance for one of the most used biomaterials, titanium-based alloy. The β-stabilizing elements Fe and Mo, which have good biocompatibility, are selected as alloying elements. The mechanical alloying method is firstly used to solve the problem of slow Mo diffusion and the formation of Ti-Mo alloy instead of solid solution. And then powder metallurgy technology is selected to prepare Ti–Mo and Ti–Mo–Fe biomaterials to tune the composition. The microstructure, phase composition, mechanical properties and anticorrosion resistance of the alloys were surveyed by optical microscope, XRD, macro- and micro-hardness tester and artificial body fluids in vitro experiment. The micrograph revealed that the Mo content plays a prominent role in the variation of microstructure of Ti–Mo and Ti–Mo–Fe alloys. And changing the β-phase will also affect the porosity and density of alloys. Artificial body fluids in vitro experiments show that Mo alloy element can enhance the corrosion resistance. But Fe element has an adverse impact on the corrosion resistance of alloys. The overall results show that the mechanical properties of the Ti–Mo and Ti–Mo–Fe alloys are greatly affected by the percentage of β-phase. By comparing the patterns of microstructure, it concludes that element of βstabilizing Mo can significantly increase the content of βTi alloy phase and the weak β-stabilizing Fe element can also promote the formation of β phase.