Prediction of TBC’s Effective Thermal Conductivity Based on DFT-Derived Material Data and Experimentally Determined Microstructural Parameters

Abstract

This article presents research on predicting the effective thermal conductivity of single-phase thermal barrier coating insulating layers, based on DFT thermal conductivity simulations, experimentally determined microstructural (porosity) data, and knowledge of interface thermal resistance. Based on the analyses, the best agreement between predictions and actual results was observed for relationships that accounted for splat geometry and interfacial resistance. The results demonstrated a certain convergence in values and trends in temperature change over the range 25 to 1100°C. The research indicates that simulations based on DFT results and assumed splat porosity and geometry can be a useful method for designing the technological process for manufacturing TBC coatings by plasma spraying.