Experimental investigation and thermodynamic modeling of the Mg–Si–Zn system

The isothermal section at 327 °C for the Mg–Si–Zn system has been determined by means of X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). No ternary compound has been observed in this work. Five three-phase regions, (Zn)+(Si)+Mg2Zn11, Mg2Zn11+MgZn2+Mg2Si, Mg2Zn3+MgZn2+Mg2Si, Mg51Zn20+MgZn+Mg2Si, and Mg51Zn20+Mg2Si+(Mg), have been determined. No appreciable ternary solubility has been detected. An optimal set of thermodynamic parameters for the Mg–Si–Zn system has been obtained by considering the experimental data from both the present work and the literature. The agreement between calculation and experiment is reasonable.