Influence of crack and pore structure characteristics on the thermal protective performance of thermal barrier coatings based on LBM.

AbstractThe architecture of porous skeletons and large crack defects in thermal barrier coatings significantly influence the thermal protective performance of the coatings. In this study, the quartet structure generation set method was applied to fabricate coatings with wedge-shaped pore structures. A temperature field prediction model was developed through the lattice Boltzmann method. The results indicate that lengthening crack length and reducing the crack inclination angle or depth elevate the peak temperature gradient and surface temperature. Specifically, the temperature gradient near a 933-μm-long crack was 1.3 times greater than that near a 248-μm-long crack, with the surface temperature reaching 1221°C. Similarly, the temperature gradient near a 50-μm-deep crack was twice that near a 200-μm-deep crack, and the surface temperature reached 1191°C. Conversely, the temperature gradient near a crack with a 30° inclination angle was 0.6 times that of a 10° crack, accompanied by a decrease in the coating surface temperature. [ABSTRACT FROM AUTHOR]