Implementation of damage model for ceramics

Abstract

This thesis presents the development and implementation of a micromechanics-based damage model for ceramics subjected to high strain rate loading. Advanced ceramics, owing to their exceptional thermal, mechanical, and chemical properties, are widely used in critical applications such as defence, aerospace, and biomedical industries. However, their brittle nature and sensitivity to flaw-induced failure demand robust constitutive models to predict fracture behaviour under dynamic conditions. A modified framework extending the ref. [19] model has been formulated, incorporating a rate-sensitive crack growth law to account for loading-rate-dependent fracture toughness. The model captures the initiation and growth of wing cracks under compressive stress states and links microcrack evolution to macroscopic behaviour through a representative population of flaws. Implementation of this model is achieved in MATLAB for uniaxial and hydrostatic compression cases. Comparative analysis with experimental data from Dionysus-Pentelicon marble validates the model's ability to replicate the strain-rate sensitivity and damage evolution observed in brittle materials. The work highlights the model’s potential in accurately forecasting failure in ceramics under dynamic loading, and suggests improvements for capturing post-peak softening and local damage instabilities.