On oxide growth fracture analysis of thermal barrier coatings based on a three-dimensional chemo-mechanical model

Abstract

The chemical mechanism is the main driven force of the thermally grown oxide (TGO) in thermal barrier coatings (TBCs), and the considerable derives of oxide growth damage are the locally additional perpetual swelling and shape deformation. A three-dimensional chemo-mechanical model is developed to explore the TGO growth based on the chemo-mechanical extended layerwise method (CM-XLWM), and the oxide growth analysis is also carried out for the TBCs with damage in this paper. The contributions of chemical reaction and ionic expansion are taken into account. The numerical simulations of the high-ambient temperature oxidation in TBCs are implemented to demonstrate the mechanism of this physical phenomenon. The chemo-mechanical coupling fracture analysis is established to delve into the principle of TGO growth and the stress states. The interface crack, transverse crack and their combination are considered, and the interactions between the TGO growth and TBC fracture are investigated as well.