A combined phase-field and cohesive zone model approach for crack propagation in layered structures made of nonlinear rubber-like materials

The development of new high-tech products often requires the optimization of structural components having layer-based arrangements. The primary focus of the present study is the analysis of the failure mechanisms that may occur in thin layer-flexible substrate systems: crack propagation through the layers, delamination at interfaces, and mixed-mode mechanisms. The phase-field (PF) approach, formulated for hyperelastic materials, is herein exploited through a series of tests to prove its capabilities in simulating the mechanical response and the crack propagation mechanisms of these composite structures. While the PF approach already captures the competition between crack propagation and delamination at the interface for bilayer composites having properties mismatch, as in the case of metallic or ceramic layers on rubber-like substrates, the framework has been further enriched with a Cohesive Zone Model (CZM) approach to model imperfect interfaces. The benefit of the coupled method can be noticed, especially for mixed-mode failure patterns, where this combination of failure mechanisms is successfully captured.