Effects of Dy³⁺-doping on the thermophysical properties of Ba₂Ybalo₅ ceramics

Ba₂Ba₂(Dy_xYb_1-x)AlO₅ ceramics were prepared by solid-state sintering in air for 10 h at 1560 °C.The influence of Dy³⁺ doping on the thermal physical properties of Ba₂YbAlO₅ was studied. The phase structure of these ceramics were identified by X-ray diffraction, which indicates that all of these ceramics have a perovskite structure. The thermal physical properties of these ceramics measurement show that the thermal expansion coefficient of them by Dy³⁺ doped significantly increased, and the maximum value of about 12.2 × 10^-6K^-1 was reached at x = 0.3. The thermal conductivity of Ba₂(Dy_xYb_1-x)AlO₅ decreased firstly and then increased with the increasing of x. For samples with the same compound point x = 0.2, the minimum value (0.998 W·m^-1·K^-1) was realized. The excellent thermal physical properties mean that these solid solutions are potential materials for ceramic layers in thermal barrier coatings.