Effect of solid solution and aging treatment on the microstructure, mechanical properties, corrosion behavior and antimicrobial properties of Ti-5Mn alloys

Abstract

In this paper, Ti-5Mn alloy was subjected to different heat treatments to explore the possibility of preparing antimicrobial Ti-Mn alloys and to examine the effect of precipitate on the properties of the alloy. The microstructure, phase composition, hardness, biocorrosion properties and antimicrobial properties of Ti-5Mn alloys after different heat treatments was analyzed by metallurgical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), microhardness tests, electrochemical tests and antimicrobial tests. The results have shown that the phase composition of the solid solution treated Ti-5Mn(T4) was mainly β -Ti phase, and the aged Ti-5Mn was composed of α -Ti phase and Ti _17 Mn _3 phase, while Ti _17 Mn _3 precipitate gradually increased with the extension of the aging time. Ti-5Mn(T4) showed the highest hardness and the best corrosion resistance and the aging process reduced the hardness of Ti-5Mn(T4) alloy. With the precipitation of Ti _17 Mn _3 , the corrosion resistance of the alloy became worse and the hardness was reduced, but the corrosion resistance of Ti-5Mn alloy was still better than that of cp-Ti. It was demonstrated that Ti-5Mn(T4) exhibited no antibacterial properties against Staphylococcus aureus , but the aging treatment improved the antibacterial property of Ti-5Mn(T4) alloy, and the antibacterial rate of Ti-5Mn alloy reached 69% after 50 h aging treatment.

Keywords

• titanium alloy
• Ti-Mn alloys
• corrosion resistance
• heat treatment
• antibacterial property