Investigation of Liquid Alloys from the Ternary Cu-Mg-Ti System: Calorimetric Study and Thermodynamic Modeling

Since there is limited information available in the literature about the thermodynamic properties of the Cu-Mg-Ti system, this work aims to determine the mixing enthalpy change for several liquid alloys from this system. To achieve the intended purpose, the applied methods were divided into two stages. The first one covered a high-temperature calorimetric measurement of the enthalpy of mixing performed at 1123–1402 K for liquid solutions in six measurement series (A–F). The obtained experimental results indicate that the liquid solutions are characterized by negative deviations from ideal solutions across the whole measured concentration range. The second stage of the study includes thermodynamic modeling. At first, based on the calorimetrically obtained experimental data and thermodynamic properties of the binary systems described by the Redlich–Kister model, a set of ternary optimized parameters for the Cu-Mg-Ti system were calculated. Then, for the calculation of the mixing enthalpy change, two models were used—the symmetrical Muggianu model and the asymmetrical Toop model. This study complements the information available in the literature and the obtained results aim to fill the gap in the current knowledge on thermodynamic properties.