Evaluation of the phase stability, and mechanical and thermal properties of Ba(Sr1/3Ta2/3)O3 as a potential ceramic material for thermal barrier coatings

Ba(Sr1/3Ta2/3)O-3 (BST) ceramic was synthesized by a solid-state reaction method. The phase stability, microstructural evolution, and mechanical and thermal properties of the BST ceramic were investigated and characterized to evaluate the potential application of BST as a top coating material for thermal barrier coatings (TBCs). The results show that BST can maintain a stable hexagonal perovskite structure up to 1600 degrees C. Anisotropic growth of the grains above 1400 degrees C was observed. Its low elastic modulus and high fracture toughness suggest a high damage tolerance for the BST ceramic. In addition, the moderate coefficient of thermal expansion and superior heat insulation capability of the BST ceramic provide this ceramic the potential to serve as a top coating material of TBCs at higher temperature.