Preparation and thermophysical properties of fluorite-type samarium–dysprosium–cerium oxides

In the present study, (Sm1−xDyx)2Ce2O7 solid solutions were synthesized by solid reaction at 1600 °C for 10 h in air. The phase structure, micro-morphology and thermophysical properties of (Sm1−xDyx)2Ce2O7 oxides were examined. XRD results indicated that pure (Sm1−xDyx)2Ce2O7 oxides with fluorite structure were prepared. SEM revealed that their microstructures were very dense and there were no other phases among the particles. The thermal conductivity and thermal expansion coefficient of the ceramics remarkably decreased through Dy-doping. Their thermal expansion coefficients were higher than that of YSZ, and their thermal conductivities were much lower than that of 8YSZ. Their excellent thermophysical properties imply that these solid solutions are potential materials for the ceramics layer in thermal barrier coatings.