Numerical simulation of damage and fracture on typical interfaces of plasma sprayed thermal barrier coatings

Based on the idea of interface damage mechanics, a new type of interface elements with three nodes was proposed. Compared with traditional interface elements, these elements have the quality of indicating the normal direction of interface with arbitrary shape. The modified model was implemented into ABAQUS by user subroutine UEL. The numerical simulation of the damage and fracture for cosine shape interface were achieved considering the rough interface of the plasma sprayed thermal barrier coatings. The calculating results show that, under thermal cycle loadings, the displacement between nodes of the interface elements is not continuous which represents the opening process of the interface crack, the damage increases with the number of thermal cycle loadings and the max damage is caused during the first cycle, the top of the interface is the critical position and the normal separation dominants, under uni-axial tension loadings, the wavy interfaces have better capability of load bearing than the linear interfaces for PS-TBC. Simulation of damage and fracture for different materials with arbitrary interface using the modified interface elements is available, and the results are reasonable.