Determination of thermophysical and thermodynamic properties, of Ag-Mg alloys. (December 2021) - Terlicka, S.
Abstract: The main purpose of this work was pioneering dilatometric measurements of alloys and intermetallic phases of the Ag-Mg system and experimental determination of the standard enthalpy of formation of alloys and intermetallic phases of this binary system, including for the first time alloys above 60 at% Mg. The scope of the work included the preparation of two alloys containing 40 and 60 at% of Mg and intermetallic phases (Ag3 Mg, AgMg, ε- AgMg3 and AgMg4 ) from high purity Ag and Mg and their qualitative and quantitative structural analysis using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM/EDS). The produced and characterized alloys have been subjected to dilatometric studies in the temperature range from room temperature up to 833 K and measurements of change of the standard enthalpy of formation by solution calorimetric method in a liquid tin as a metallic bath. The addition of Mg to Ag generally increased the linear coefficient of thermal expansion compared to pure silver. The standard enthalpies of formation of the prepared alloys were consistent with literature data, and the observed maximum differences were c.a. 1.7 kJ/mol at. Highlights: The X-ray Diffraction analysis of selected Ag-Mg alloys. Microstructure observation and chemical composition studies of obtained Ag-Mg alloys. Thermal expansion measurements of alloys from Ag-Mg system. Standard enthalpy of formation of Ag-Mg alloys and intermetallic phases.