Establishing TBC Random Pore Model Based on Random Media Theory

The local variety of density and elastic modulus in thermal barrier coatings (TBCs) caused by pores and cracks is described by the spatial autocorrelation function and statistical parameters in this paper firstly, based on the random media theory and statistical analysis method. A novel TBCs random pore model (TRPM) is proposed and established through rebuilding the continuous random media model (RMM) by extremum search method and parameter optimization for the characteristics of coating porosity and anisotropy orientation. The comparison is carried out between the image of TRPM and scanning electron microscope (SEM) of ZrO2 coating with porosity 1%, which shows TRMM can better describe the morphology characteristics of pores and cracks in TBCs. This work is of great significance for determining the theoretical relation of TBCs pore character and coating performance, and investigation on the calculation of coating performance.