The partial isothermal section of the Mg-Er-Si Ternary System at 500°C

Abstract

Abstract The partial isothermal section of the Mg-Er-Si ternary system in the Mg-Corner at 500°C has been studied through the equilibrated alloy method by using X-ray diffraction analyses and scanning electron microscopy assisted with energy dispersive spectroscopy of X-ray (SEM-EDS). There is convincing evidence for three compounds which have been clarified to be existing in equilibrium with the a-Mg solid solution at 500°C, i.e. Mg2Si, Er2MgSi2 and Er5Mg24. The results show that the partial isothermal section in the Mg-Corner consists of four single phase regions, five two-phase regions: α-Mg+Er5Mg24, α-Mg+Mg2Si, Mg2Si+Er2MgSi2, α-Mg+Er2MgSi2 and Er5Mg24+Er2MgSi2 and two three-phase regions: α-Mg+Er5Mg24+Er2MgSi2 and α-Mg+Mg2Si+Er2MgSi2. The homogeneity ranges of Mg solid solution as well as the solid solubilities of the intermediate phases at 500°C are reported. The phase of Er5Mg24 (cI58-Mn-type), Mg2Si (cF12-CaF2-type) and Er2MgSi2 have been mainly studied.