Constitutive model of multiphase ceramics based on microcrack damage evolution

The damage evolution of microcracks that dispersed in eutectic composite ceramics is an important factor leading to fracture failure. We propose a meso damage model (CMMC), which uses our proposed two-scale cellular model with microcracks, and fully considers the characteristics of the microstructure on the eutectic composite ceramics, thus providing a more objective structural modeling. In addition, there are two significant features existing in CMMC: One is to use the interaction direct derivative (IDD) estimate method to calculate the additional flexibility increment caused by a single open elliptical microcrack, which considers the spatial orientation of the microcrack. The other is that the additional flexibility tensor from the microcrack system is obtained by introducing probability density function and selecting appropriate microcrack growth criteria. Experiments on the related datasets show that CMMC achieves the consistent results compared with the experimental data. Furthermore, the effects of microcrack aspect ratio and microstructure parameters on the effective properties of multiphase ceramics were analyzed by using numerical method. •Damage evolution of microcracks in composite ceramics leading to fracture failure.•A meso damage model based on microcrack damage evolution is proposed.•Microcrack aspect ratio affects effective properties of multiphase ceramics.•Microstructure parameters influences effective properties of multiphase ceramics.•The additional flexibility tensor from the microcrack system is obtained.