Parallel Molecular Dynamics Simulations and Immersive Visualization of Thermal Barrier Coating Components: Thermally Growing Oxide and Yttria Stabilized Zirconia

Non-equilibrium parallel molecular dynamics simulation is used to determine the thermal conductivity of Alumina in the [2 1 1 0]direction at 1200 K: When thermal expansion is not allowed it is found to be 3.45 W/mK, while with thermal expansion it is 2.95 W/mK. A short ranged empirical potential for Yttria stabilized Zirconia (YSZ) is developed by fitting to available ab initio and experimentally derived data for Zirconia. With this potential, simulations of YSZ at 2073.16 K, with 4.9–23.1 mol% of Yttria in Zirconia, shows diffusing Oxygen and non-diffusing Zirconium and Yttrium atoms as expected. However, the diffusion constant of oxygen increases with the Yttria content, inconsistent with simulations with long range interactions showing a peak around 10 mol% of Yttria and also inconsistent experiment at 923 K. Visualizing the dynamics of atoms in Alumina, when driven by a heat-current forcing perturbation, shows phonon-like modes indicating the need for smaller perturbation or an alternate method to determine thermal properties.