Structural Aspects of Soft Ferromagnetic Mg-Zn Based Intermetallics Prepared by Die Casting

Abstract

In this research, different types of Mg-Zn based intermetallics that appear in the Mg-Zn alloy system were synthesized by conventional casting route. Consequently, the structural, mechanical, electrical, and magnetic properties of these Mg-Zn intermetallics were thoroughly studied. Every casting underwent a trivial loss of Mg by oxidation which resulted in slightly higher weight percentages of Zn. X-ray Diffraction (XRD) analysis confirmed the coexistence of several intermetallics in each sample. The morphology of the samples was studied under Optical and Field Emission Scanning Electron Microscopes and the phases were identified by Energy Dispersive Spectroscopy (EDS). Differential Scanning Calorimetry (DSC) analysis further confirmed many of the available phases found. Mainly five intermetallics i.e., Mg51Zn20, MgZn, Mg4Zn7, MgZn2 and Mg2Zn11 were observed in the structures. The cast sample which is rich in Mg2Zn11 showed the highest compressive strength (122.6 MPa) and electrical conductivity of 10.47 S/m. From Vibrating Sample Magnetometry (VSM) analysis it was found that three of the samples are soft ferromagnets whereas only the samples abundant in MgZn2 content showed paramagnetic behavior with maximum magnetization of 0.66 emu/gm.