In-situ synthesis of gadolinium niobate quasi-binary composites with balanced mechanical and thermal properties for thermal barrier coatings

Abstract Yttria-stabilized zirconia (YSZ) has been used as a thermal barrier coating (TBC) material in gas turbines for several decades. Although continuous efforts have made to develop novel TBC materials that can work at higher temperature, no single other than YSZ all the desired attributes TBCs. In this paper, we report in-situ synthesis of quasi-binary GdNbO 4 /Gd 3 NbO 7 composites based on simple Gd 2 O -Nb 5 binary phase diagram. The fracture toughness these is remarkably enhanced compared with value predicted by rule mixtures because ferroelastic domain switching more activated due residual stress composites, which triggers crack defections enlarged process zone. Additionally, provides low conductivity substantial chemical inhomogeneity, diffuses phonons. /GdNbO exhibits balanced 1.6 W/(m·K) 1073 K and 2.76 MPa·m 0.5 , values are among best comprehensive properties obtained new materials. demonstrates feasible approach designing be easily fabricated.