Thermophysical and mechanical properties of YTaO4 ceramic by niobium substitution tantalum

Abstract In this paper, the Y(Ta1-XNbX)O4 ceramics synthesized via a solid-state reaction were researched as promising thermal barrier coatings (TBCs). The Y(Ta1-XNbX)O4 exhibits far less thermal conductivity (~1.5 W·m−1·K−1, 900 °C) than 8YSZ (~2.5 W·m−1·K−1, 900 °C). The thermal expansion coefficients (TECs, ~11.0 × 10−6 K−1, 1200 °C) of Y(Ta1-XNbX)O4 ceramics are higher than the TECs of 8YSZ (~10.0 × 10−6 K−1, 1200 °C), La2Zr2O7 (~9.0 × 10−6 K−1, 1200 °C) and other TBCs. Besides, Y(Ta1-XNbX)O4 exhibits outstanding mechanical properties, including low Young's modulus (115–135 GPa) and high hardness (8–10 GPa). The excellent thermophysical and mechanical properties indicate that Y(Ta1-XNbX)O4 ceramics are promising as potential TBC materials for in-depth research.