Microstructure and Mechanical Properties of Mg-Zn-Ca-Zr Alloy for Biomedical Application

The microstructure and mechanical properties of the as-cast Mg-Zn-Ca-Zr alloys were investigated in this study. The results showed that the alloy was mainly composed of α-Mg solid solution and the secondary phases of Ca2Mg6Zn3. The grain size of alloys decreased from 82 μm to 38 μm with Zr content from 0.1% to 0.5%. The addition of Zr greatly improved the ultimate tensile strength (σb) and elongation (e), while slightly improved the tensile yield strength (σ0.2). The σb, e and σ0.2 of the Mg-4Zn-0.5Ca-0.5Zr were 196MPa, 85MPa and 16.1% compared with the other two alloys. The reason was that grain size refinement strengthening enhanced the mechanical properties.