Novel bioactive Ti-Zn alloys with high strength and low modulus for biomedical applications

Abstract

To address new challenges in current biomedical titanium alloys, novel binary Ti-Zn alloys with high strength, low elastic modulus, excellent corrosion resistance, and intrinsic bioactivity, were prepared via hot-press sintering. In this paper, the microstructure, mechanical properties, corrosion behaviors, and in vitro biological properties of the Ti-Zn alloys were systematically investigated. The Ti-Zn alloys mainly consist of α-Ti and Ti2Zn phases, in which the Ti2Zn phase plays a good role in precipitation strengthening, and the number gradually increases with increasing the Zn contents. All of the compressive strength, elastic modulus, and nanohardness of the Ti-Zn alloys increase first, and then decrease with increasing the Zn contents. The Ti-Zn alloys show great corrosion resistance with the polarization resistance of more than 104 Ω/cm2, and the resistance continuously increases with increasing the immersion times in SBF solution. The Ti-Zn alloys possess hydrophilic surfaces with contact angles of approximately 34° ∼60°. The concentration of Zn ions released from the Ti-20Zn alloy in 0.9% NaCl solution is much lower than that of the biosafety intake. The Ti-Zn alloys exhibit favorable cytocompatibility, which are very beneficial to the spread, proliferation, and differentiation of the MC3T3-E1 cells. The above-mentioned results suggest the Ti-Zn alloys can be promising candidates for biomedical applications.