Multiple-phase-field modeling for fracture of composite materials

Abstract

Fracture behavior of composite materials is a challenge in numerical simulations due to the heterogeneity introduced by reinforcements. Based on the phase-field fracture model, a multiple-phase-field ductile fracture model is developed by using different phase field descriptors to characterize multiple cracking behaviors, involving different fracture mechanism such as brittle fracture and ductile fracture for composite materials. A novel degradation function is introduced to couple different fracture mechanism, i.e., brittle damage and ductile damage. We also extended the proposed multiple-phase-field ductile fracture model to a general formulation which can incorporate with different constitutive models. The main findings of this article are three folds: (1) accuracy and robustness of the proposed model are guaranteed by comparing the present results and previous work; (2) plastic localization and accumulation is the main reason for crack initiation and propagation; (3) enhanced load carrying ability and ductility are obtained in composite structures with hard/tough inclusions.