The microstructure of thermally sprayed ceramic coatings ischaracterized by the existence of various pores andmicrocracks. The porous microstructure makes coatingdesirable for thermal insulation, but this uniquemicrostructural feature also gives rise to anelastic responseunder tension and compression loads. Detail investigations ofcurvature measurements of ceramic coated substrate indicatethe coatings to exhibit anelastic behavior composed ofnonlinear and hysteresis characteristics.In this paper, the mechanisms of such behaviors were studiedfrom curvature-temperature measurements and finite elementanalysis through modeling the microstructure of yttriastabilized zirconia (YSZ) coating. Computational modelscontain numerous randomly distributed pores and microcrackswith various sizes, aspect ratios, locations and orientations.The effects of such attributes of pores and microcracks oncoating anelastic behavior were studied by simulations ofcurvature change during thermal cycles.
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