Application of extreme value statistics to internal pore distribution in ceramics and prediction of size dependency of strength scatter

Abstract

To implement ceramics in high-reliability components, it is necessary to understand the strength scatter caused by the stochastic distribution of defects in ceramics. In this study, we propose a numerical simulation method to predict the strength scatter of ceramics and its size dependency using microstructural data obtained using X-ray computed tomography and scanning electron microscopy. The generalized Pareto (GP) model, a type of extreme value statistic, was applied to treat the three-dimensional distribution of the pore size. Further, we predicted the bending strengths of the four types of bending tests with different effective volumes, and the results corresponded with the experimental results. Additionally, the method was applied to specimen models with different discretization sizes to verify the advantages of the GP model. The results show the effectiveness of the proposed method for the specimen size dependence of the bending strength and specimen discretization size independence.