• Ti3Mn and Ti6Mn alloys were studied at 25 °C, 40 °C (simulating fever conditions) and pH = 1.2 (infection). • Mn addition refines microstructure and stabilizes the β phase in Ti-xMn alloys. • Lower elastic modulus than Ti6Al4V improved the compatibility with bone tissue. • Mn promotes the formation of protective Ti-Mn oxide, enhancing the passivity. Among titanium (Ti) alloys, titanium-manganese alloys (TixMn, where x = 3 and 6 wt%) are highlighted for their specific strength, deformability and cold resistance, making them promising candidates for medical applications. This study investigates their microstructural characteristics, mechanical response and electrochemical behavior under various physiological conditions, including room temperature (25 °C), fever simulations (40 °C) and highly acidic environments (pH 1.2). Metallographic and scanning electron microscopy revealed equiaxed polyhedral grains with dual phase α + β microstructure. Increasing Mn content promoted β-phase stabilization confirmed by the characteristic β-phase peaks in the XRD patterns. Microhardness and nanoindentation testing showed that hardness increased with applied load and Mn content. The elastic modulus was lower than that of Ti6Al4V, suggesting improved mechanical compatibility with bone tissue. The corrosion resistance depends on environmental conditions: Ti3Mn performs best at room temperature, whereas Ti6Mn shows enhanced passivity at 40 °C due to a protective oxide layer. Both alloys are less resistant in highly acidic environments due to Mn dissolution. The studied TixMn alloys display promising structural, mechanical and electrochemical properties for biomedical applications, particularly in bone implant design, while offering a more sustainable and cost-efficient alternative to conventional Ti alloys.
Jiménez-Marcos et al. (Sun,) studied this question.