Chapter 15 - Phase field–based peridynamics damage model: Applications to delamination of composite structures and inelastic response of ceramics

Abstract

The phase field–based peridynamics (PD) damage model is applied to study the delamination of composite structures and inelastic response in ceramic materials. Degradation functions are used to model interfacial cohesive damage involved in the delamination process and the critical energy release rate for fracture. Our model treats delamination under different modes of loading as problems that differ only in their boundary conditions and thus offers a relatively more unified approach for delamination growth. Delamination under mixed mode loading conditions can be handled naturally compared to the popular cohesive zone model (CZM) which makes use of an empirical interaction criterion. We present numerical simulations on mode I, mode II, and mixed-mode delamination cases and validate these results against experimental evidence. We also develop a phase field–based PD approach for the Deshpande and Evans (DE) constitutive model for ceramics, which considers elasticity, plasticity, and damage. Replacing the damage evolution equation in the DE model by a phase field–based equation, we eliminate a few limitations of the former. Using the present approach, a spherically cavity expansion problem is solved through dimensional reduction and compared with the DE model.