Experimental determination and thermodynamic calculation of phase equilibria in Ag-Zr-Y system

The phase equilibria of the Ag-Zr-Y system at 800, 600 and 500 degrees C were investigated by means of X-ray diffraction (XRD) and scanning electron microscope (SEM) with energy dispersive X-ray spectrometry (EDS) techniques. The solubilities of Y in the Ag2Zr and AgZr phases and of Zr in the Ag51Y14, Ag2Y and AgY phases were measured, and no ternary compound was found in these isothermal sections. By means of the CALPHAD method, thermodynamic parameters of the Ag-Zr-Y system were assessed based on the experimental data from the present work and the literature. Substitutional solution model was used to describe the solution phases and sublattice models were used to describe binary compounds. A set of self-consistent and accurately described thermodynamic parameters of the Ag-Zr-Y system were obtained. The representative isothermal sections and liquidus projection were calculated, and the Hill reaction scheme of the Ag-Zr-Y system was constructed. The calculated results are in agreement with the experimental data.