Theoretical investigations on mechanical anisotropy and intrinsic thermal conductivity of YbAlO3

Abstract

YbAlO3 is a promising candidate of environmental barrier coating (EBC). However, its mechanical and thermal properties are not well understood. In this work, the structural, mechanical, and thermal properties of YbAlO3 are studied by combining density functional theory (DFT) and chemical bond theory calculations. Heterogeneous bonding nature and distortion of the structure are revealed based on the calculated equilibrium crystal structure. Full set of elastic constants, polycrystalline mechanical properties and elastic anisotropy of YbAlO3 are predicted. In addition, the temperature-dependent thermal conductivity of YbAlO3 are estimated and the minimum thermal conductivity is determined to be 1.15Wm−1K−1. The theoretical results highlight the potential application of YbAlO3 as a thermal and environmental barrier coating (T/EBC).