Peridynamic modeling of elastic bimaterial interface fracture

Abstract

A general peridynamics-based framework for elastic bimaterial interface fracture analysis is established. In this frame, the formation of peridynamic interface bond force is presented for nonlocal interface modeling, and the energy release rate and mode mixity of interface cracks are computed with peridynamic model. A modified critical energy density (MCED) criterion considering both interfacial and materials fracture toughness is proposed for peridynamic bond failure analysis, and the bond failure competition strategy is considered for crack path selection of an interface crack along or kinking out of the interface. Then, four tests of a bimaterial plate under uniform tensile stress, asymmetric bimaterial cantilever beams (ABCB), bimaterial single edge notched (BSEN) and four-point shearing (FPS) tests are investigated for the model verification and application. The deformation and fracture behaviors of these specimens are predicted with the proposed peridynamic models, and compared to those from FEM, theoretical and experimental solutions. The results show that the proposed peridynamics-based method can successfully capture the characteristics of bimaterial interface fracture, including the delamination fracture, kinking nucleation and crack path selection of interface cracks.