Experimental study of the phase equilibria in the Mg-Zn-Ag ternary system at 300 °C

The phase equilibria in the Mg-Zn-Ag ternary system at 300 °C were investigated using three diffusion couples and 35 key samples. Scanning electron microscopy (SEM) equipped with energy-dispersive spectroscope (EDS) and X-ray diffraction (XRD) techniques were used for homogeneity ranges and crystal structure determination. Large solid solubility limits, due to substitution among Mg, Zn and Ag atoms in Mg3Ag and MgZn2 phases, were observed in the present work. Solid solubility limits of Ag and Zn in the hcp (Mg) phase were found to be less than 1 at.%. The extended solid solubilities of the Mg12Zn13, Mg2Zn3, MgZn2 (C14), Mg2Zn11, Ag5Zn8 and hcp (AgZn3) sub-binary compounds were also determined in the Mg-Zn-Ag ternary system. In addition, a bcc continuous ternary solid solution forms between MgAg (bcc_B2) and AgZn (bcc_A2) at 300 °C.