Design and preparation of a biomedical titanium alloy with low elastic modulus and high antibacterial property based on Ti-Mo-Ag system

Titanium and titanium alloys have been widely used as biomedical materials as a result of low density, high specific strength, good biological propertise, good mechanical compatibility and easy processing. However, problems such as stress shielding and bacterial infection often occur in the clinical application. In this paper, Ti-15Mo-xAg (x = 10, 12) alloys were designed and prepared to obtain low elastic modulus and excellent antibacterial ability. We studied the microstructure, mechanical properties, antibacterial properties and cytocompatibility by scanning electron microscopy, differential scanning calorimeter, X-ray diffraction, micro-hardness instrument and plate counting method. The calculated results indicated that Ti-15Mo alloys with different Ag contents could be beta-type or near beta-type alloy with potential of a low elastic modulus. Microstructure results demonstrated that the increasing Ag content from 10 wt% to 12 wt% increased the phase transformation temperature and resisted the formation of omega phase in Ti-Mo-Ag system. Both the elastic modulus and the antibacterial ability were significantly influenced by the ageing treatment and Ag content due to the phase constitution, and high Ag content and the precipitation of Ti2Ag were beneficial to the antibacterial performance but increased the elastic modulus. Cell assessment showed that Ti-Mo-Ag alloys did not have cytotoxicity to MC3T3. Ti-15Mo-10Ag alloy exhibited strong antibacterial rate of 99.5%, good cellular compatibility and low elastic modulus of 85 GPa, which suggests that this alloy might be a highly competitive medical material. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

Titanium and titanium alloys have been widely used in the biomedical field due to their excellent physical, chemical, and biological properties. In this study, Ti-15Mo-xAg alloys with low elastic modulus and excellent antibacterial ability were designed and prepared. The microstructure, mechanical properties, antibacterial properties, and cytocompatibility were investigated. The results showed that Ti-15Mo-10Ag alloy exhibited a strong antibacterial rate of 99.5%, good cellular compatibility, and a low elastic modulus of 85 GPa, suggesting that this alloy may be a highly competitive medical material.