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Abstract: The effects of Mn substitution for Mg on the microstructure, mechanical properties, and corrosion behavior of Mg69−xZn27Ca4Mnx (x=0, 0.5 and 1at.%) alloys were investigated using X-ray diffraction, compressive tests, electrochemical treatments, and immersion tests, respectively. Microstructural observations showed that the Mg69Zn27Ca4 alloy was mainly amorphous. The addition of Mn decreases the glass-forming ability, which results in a decreased strength from 545MPa to 364MPa. However, this strength is still suitable for implant application. Polarization and immersion tests in the simulated body fluid at 37°C revealed that the Mn-doped Mg–Zn–Ca alloys have significantly higher corrosion resistance than traditional ZK60 and pure Mg alloys. Cytotoxicity test showed that cell viabilities of osteoblasts cultured with Mn-doped Mg–Zn–Ca alloys extracts were higher than that of pure Mg. Mg68.5Zn27Ca4Mn0.5 exhibits the highest bio-corrosion resistance, biocompatibility and has desirable mechanical properties, which could suggest to be used as biomedical materials in the future. [Copyright &y& Elsevier]

Abstract: Mg69Zn27Ca4 with a spot of Fe particle-reinforced alloys was synthesized by Cu-mold injection casting using industrial raw materials. The microstructure, mechanical properties and corrosion resistance of these Mg-based alloys were studied by X-ray diffraction, differential scanning calorimeter, compressive testing and electrochemical measurements, respectively. The Mg69Zn27Ca4 alloy can be controlled to become fully amorphous using the industrial raw materials. With Fe particle addition, ductile α-Mg and Mg–Zn dendrites were embedded in the amorphous matrix, which enhanced the compressive strength and fracture strain. The Mg69Zn27Ca4 glassy alloy and Mg69Zn27Ca4/Fe alloy remarkably improved the corrosion resistance in 3.5wt% NaCl solution compared with AZ31 and pure Mg. Therefore, Mg69Zn27Ca4 and Mg69Zn27Ca4/Fe alloys have high potential as engineering materials. [Copyright &y& Elsevier]