Anisotropic Mechanical and Thermal Properties of Nd₂SrAl₂O₇

Abstract:

For a long time since the anisotropy basically confined to a single crystal, used as a polycrystalline ceramic materials generally considered to be isotropic. In this paper, the anisotropic mechanical, thermal expansion coefficient and thermal conductivity of a double perovskite slab-rocksalt layer Nd₂SrAl₂O₇ was studied by first principles as an example. The method is using density functional theory (DFT) and crystal parameters, which has been used to calculate the modulus of elasticity of anisotropic in a three-dimensional space. While combined with traditional thermal conductivity theory, we have obtained the tensor of thermal diffusion, thermal conductivity in 3D space for the first time in the world within no. The results are in good agreement with the experiment. The advantage of method is avoiding the difficulty of experimental measurement, reducing the time and obtaining relatively accurate results.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 975-979
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.975
• Online since: June 2012
• Authors: J. Feng, Z.C. Huang, R. Zhou, Wei Pan
• Keywords: Ceramic, Elastic Modulus, Thermal Conductivity (TC), Thermal Expansion

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