Ceramic thermal barrier coatings (TBC) can exhibit premature in-service failure due to spallation as a consequence of exposure to elevated temperatures, aggressive environments, and cyclic loading. Lifetime assessment for TBC-systems requires methods for characterizing damage accumulation that lead to spallation as a function of loading history. In this study controlled flaws were introduced into cylindrical TBC coated specimens by indentation. These controlled flaws were introduced to ultimately characterize the interfacial fracture toughness of thermally cycled specimens, as well as of specimens that underwent more realistic memo-mechanical cycling with a thermal gradient across the coating. Indentation flaws introduced before testing were used to investigate the topcoat spallation phenomenon and bond coat rumpling behavior as a function of thermo-mechanical cycling conditions.
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