The Mechanical And Corrosion Resistance Of Mg-Zn-Ca-Ag Alloys: The Influence Of Ag Content

Biomedical magnesium alloys have become an ideal material for degradable implantsbecause of their similar density and elastic modulus with human bone. In this study, Mg3Zn-0.2Ca-xAg (x = 0%, 0.1%, 0.3%, 0.5%, 0.7%, wt.%) alloys were fabricated to enhance thecomprehensive properties of the Mg-3Zn-0.2Ca (wt.%) alloys. The microstructure showsthat the alloy possesses relatively smaller grain size of 2.08 mu m when the addition of Agis 0.3 wt.%. The Mg-3Zn-0.2Ca-0.3Ag also owns the best mechanical properties whose elongation, yield strength and tensile strength are 4.57%, 5.7%, and 2.4%, respectively, higherthan that of Mg-3Zn-0.2Ca. The electrochemical experiments shows that Mg-3Zn-0.2Ca0.3Ag has lower corrosion current density (30.5 mu A/cm(2)), which indicates that its corrosionresistance has been improved. After immersed in simulated body fluids at 37. C for 15 days, the hydrogen release rate and degradation rate of the Mg-3Zn-0.2Ca-0.3Ag is significantlylower than that of Mg-3Zn-0.2Ca. In addition, the cytotoxicity test with L 929 cells showsthat Mg-3Zn-0.2Ca-0.3Ag alloy has good biocompatibility. (C) 2020 The Author(s). Published by Elsevier B.V.