Microstructures and damping capacity of Mg-6Zn-2.8Er-1Cd-0.6Zr magnesium alloy as-casted

The microstructures of Mg-6Zn-2.8Er-1Cd-0.6Zr magnesium alloy as-casted was studied. The phase composition was analysed by optical microscope (OM), and the morphology of the second phase was observed by Scanning Electron Microscopy (SEM). The damping capacity of Mg-6Zn-2.8Er-1Cd-0.6Zr magnesium alloy as-casted was studied by dynamic mechanical analyser (DMA). The studies result of this paper illustrate the microstructure of Mg-6Zn-2.8Er-1Cd-0.6Zr as-casted alloy is comprised of a-Mg+Mg-Zn+Mg-Zn-Er. The average size of grains of the studied alloy is 50μm or so. Mg-6Zn-2.8Er-1Cd-0.6Zr alloy as-casted exhibits higher damping performance. At higher strain amplitude rang from 4×10⁻⁴ to 1.2×10⁻³, the damping value varies from 0.010791 to 0.012708, with an average of 0.01186. The damping capacity mechanism of Mg-6Zn-2.8Er-1Cd-0.6Zr alloy accords with Granato and Lücke (G-L) theory.