Thermal barriers made up by a ceramic top coating and a metallic bond coating are subjected to thermal cycles in service. The thermal stresses vary during the cycles and the residual stresses change as a result of plastic flow and creep. The stress state in thermal barrier coatings during a thermal cycle has been examined with a finite element method using temperature dependent material data. The calculated results were verified by measurements of the residual stresses with the layer removal technique before and after cycling of specimens heated in furnace with air environment. According to the simulation of a thermal cycle to 700 ° C, using a finite element method, the bond coat is approximately stress free after 1 hour dwell time. Thus, the residual stresses after a thermal cycle is a result of thermal expansion mismatch and temperature drop.

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