Phase equilibria of the Cu-Ni-Zr ternary systems at 800 °C and thermodynamic assessment and metallic glass region prediction for the Cu-Ni-Zr ternary system

Abstract

Cu-Zr based alloys have been used as metallic glass alloys owing to their high glass forming ability (GFA). Ni is added into these alloys to enhance their mechanical property and improve GFA. These Cu-Ni-Zr ternary alloys have a high potential to be used as metallic glass alloys. Herein, we investigated and assessed thermodynamically the phase equilibria of the Cu-Ni-Zr ternary system at 800°C using the calculation of phase diagram (CALPHAD) method based on the experimental data. Thirty-three alloys were prepared using the arc melting method. At 800°C, the isothermal section of the Cu-Ni-Zr ternary system composed of 15 single-phase regions, 20 two-phase regions, and 8 three-phase regions; no ternary intermetallic compounds were found. In addition, a continuous solid solution was formed by the Cu10Zr7 and Ni10 Zr7 phases at 800°C. Furthermore, the thermodynamic parameters were optimized using the phase equilibrium data. The calculated isothermal section and metallic glass region prediction of the Cu-Ni-Zr ternary system were reasonable and satisfactory compared with the literature data.