Experimental investigation of phase relations and thermodynamic properties in the ZrO2–TiO2 system

Phase relations in the ZrO2–TiO2 system were studied experimentally using X-ray diffraction (XRD), scanning electron microscopy combined with dispersive X-ray spectrometry (SEM/EDX) and differential thermal analysis (DTA). The homogeneity ranges of ZrO2 and TiO2, as well as high temperature disordered β-(ZrxTi1−x)2O4 compound were defined in the temperature range of 1700-2040 K. Temperature and composition of eutectic reaction were measured. The standard enthalpy of formation of the β-ZrTiO4 compound was obtained using high-temperature oxide-melt solution calorimetry. High temperature heat capacity measurement for the β-ZrTiO4 compound was performed in the temperature range from 250 K to 1200 K. Thermodynamic description of ZrO2–TiO2 system has been derived based on obtained experimental results and data from literature.