Effect of alloying with a second components on the biocompatibility and mechanical properties of Ti–Mo alloys

This paper presents the results of a study on two titanium-based alloys — Ti–10wt.%Mo and Ti–15wt.%Mo — aimed at assessing their potential for use as base materials in implantable medical devices for osteosynthesis. The alloy samples were examined in three conditions: as-fabricated, after annealing at 1000 °C, and after high-pressure torsion. The microstructure of the alloys was analyzed using scanning electron microscopy and X-ray diffraction. The Young’s modulus, microhardness, and nanohardness values were measured, and the effect of the alloys on the viability and surface adhesion of human multipotent mesenchymal stromal cells during in vitro incubation was investigated. Comparative analysis of the obtained results revealed that the annealed Ti–15wt.%Mo alloy sample is the most promising candidate for orthopedic applications, as it exhibits an optimal combination of good biocompatibility, enhanced stimulation of cell adhesion, and relatively low microhardness (283 HV) and Young’s modulus (106 GPa).

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