Study of Thermodynamic Properties of Nonstoichiometric Phase with Compound Energy Model

Using compound energy model (CEM), the thermodynamic properties of and were evaluated.The evaluation was based on the optimization of ZrO2-CeO2 and ZrO2-CeO1.5 systems, as well as the miscibility gap inCeO1.5-CeO2 system. Except the cubic fluorite structure phase assessed with compound energy model, all the other solutionphases were assessed with subsitutional solution model. The model parameters were evaluated through fitting the selectedexperimental data by means of thermodynamic optimization. A set of parameters with thermodynamics self-consistency wasobtained and satisfactorily described the complex relation between y in and the partial pressure of oxygen atdifferent temperatures, also the interdependence among miscellaneous factors such as temperature, oxygen partial pressure,seem to be reasonable when put into the explanation of pressureless sintering of CeO2-stabilized ZrO2 powder compacts at acontrolled oxygen partial pressure.