Micro/nano-indentation is a very important technique to characterize the mechanical properties and elastic/plastic response behavior of ceramic coatings system. A thermal barrier coating model containing randomly distributed circular pores was developed in ABAQUS using a secondary development plugin Python to investigate the effect of pores on the micro/nano-indentation response of thermal barrier coatings prepared by atmospheric plasma spraying (APS). Based on a finite element model of a thermal barrier coating containing random circular pores

the extended finite element method was used to simulate and analyze the crack propagation within the ceramic layer during the icro/nanoindentation experiments

and to further investigate the interaction between micro-cracks and pores

and the patterns of crack emergence and propagation within the coating. The results show that the distribution characteristic of the residual stress could be changed due to existence of the pores because the pores would release some stress concentration more or less during the loading and unloading processes. The presence of pores in the ceramic layer caused cracks to propagate in the direction of the pores and prevented crack further propagate to some extent. Correlating this work with the experimental results from micro/nano-indentation experiments may help us to predict the actual mechanical properties of thermal barrier coating systems.