抄録
Understanding and thereby lowering thermal conductivity by introducing nano-meter sized structural defects is a crucial issue for the development of the thermal barrier coating. Molecular dynamics (MD) calculations using a perturbation method were conducted to evaluate the thermal conductivity of pure ZrO2 and Y2O3 doped ZrO2. It was found that the vibration of the O ions dominates the overall thermal conductivity at low temperature. The partial thermal conductivity of the O ions decreased dramatically with increasing temperature while that of the Zr ions changed only slightly, resulting in an overall decrease in the thermal conductivity. Comparison with results from MD calculations using the mean field theory showed that scattering of phonons by O vacancies is larger than that by Y ions in Y2O3 doped ZrO2.Acknowledgment: This work was performed as a part of the Nanostructure Coating Project carried out by the New Energy and Industrial Technology Development Organization.
