A 3D finite element model of thermal barrier coating (TBC) system considering the interface morphology is established by using the finite element method. By calculating the change of residual stress at the interface when cooling from high temperature to room temperature

the influence of interface geometry on the residual stress of the TBC system is studied. The results show that the thickness of the TGO layer not only affects the magnitude of the residual stress

but also affects the stress state

and the thicker the TGO layer

the higher the residual stress level in the same model. The increase of the interface amplitude will increase the residual stress at the interface of the bond layer (BC) – TGO

but its influence on the residual stress at the interface of the ceramic layer (TC) – TGO is more complicated. The effect of increasing the interface wavelength will reduce the residual stress level to some extent; The 3D hybrid roughness parameter has less effect on the residual stress. Therefore

the thickness of the oxide layer

the interface amplitude and the wavelength will greatly affect the residual stress of the TBC

which in turn affects the stability of the TBC system

and the thickness of the oxide layer has a decisive significance on the failure location of the coating.