Effect of Zr content on the microstructure, mechanical properties, electrochemical behavior, and biocompatibility of Mg–3Zn–xZr alloy using powder metallurgy

Abstract In this study, Mg–3Zn–xZr ( x = 0, 0.5, 1, 2 and 3) alloy were produced using powder metallurgy incorporating high-energy ball milling. Scanning electron microscope (SEM), energy dispersive X-ray (EDX) analyzer and X-ray diffraction (XRD) have been used to investigate the microstructure, chemical composition and phase distribution of the samples. XRD results show that the Mg solid solution wholly formed, and the milled powders were single phase, and no secondary phase was observed. While the secondary phases were formed after sintering. Hardness of Mg–Zn–xZr sample increased from 58.8 Hv (for Zr = 0) to 87.81 Hv with addition of 3 wt.% Zr. The result shows that the corrosion potential of Mg–Zn–Zr alloy was more positive than Mg–3Zn. However, the Mg–3Zn–Zr alloy exhibited higher corrosion current than Mg–3Zn due to galvanic effect of Zr rich area. All of Mg–3Zn–Zr alloys showed better antibacterial and biocompatibility properties than Mg–3Zn alloy due to the presence of Zr as additive. According to the mechanical, corrosion, and biological evaluations in this study, it can be concluded that the Mg–3Zn–1Zr alloy can be used as a suitable biomaterial for the use of orthopedic implants.