Impact damage model for ceramic materials

The fracture process in ceramic materials upon impact loading is complex in nature. Most often, the brittle ceramic deforms inelastically due to microcracking under shock (compression) loading. At high‐velocity impact, the shock generated microcracks rapidly open and extend under subsequent tension (due to the release waves from the stress‐free boundaries) leading to complete pulverization of the ceramic materials. The main objective of this paper is to model the damage process in ceramics due to impact loading. A computationally oriented continuum damage‐based constitutive model is considered. Several modifications incorporating strain rate and damage effects on the compressive strength have been introduced into the model. Results are presented in terms of numerical simulations of a plate‐impact test configuration. Effects of the model parameters on the compressive strength and spall strength are described. The proposed damage model has been used successfully to match the measured stress history from a p...