Phase-field modeling of fracture in strain-hardening elastomers: Variational formulation, multiaxial experiments and validation

Abstract

Elastomeric sealing and rubber-like materials find applications in a variety of industrial domains. Understanding the behavior of such materials and description of fracture in elastomeric components is therefore decisive in the choice of materials for realizing newer concepts and product designs. Over the years, phase-field modeling of fracture has proven to be a capable tool in handling arbitrary cracks and their propagation in an adequate manner. Nevertheless, a large number of associated models are based either on small-strain assumptions or focus on phenomenological hyperelastic models, both of which are seldom of interest to industrial-grade rubbers. In this work, we present a way to perform phase-field fracture simulation in conjunction with the renowned Gent model of hyperelasticity, wherein the singularity issue near the limit of chain stretch is handled adequately. An extension of an existing model is proposed to describe crack propagation in multiaxial loading cases. The salient features of the model are demonstrated by suitable numerical examples. Furthermore, we perform material characterization experiments on an industrially relevant silicone material and use the above framework to determine the model parameters of this elastomeric adhesive. Additionally, the ability of the model to predict stress–strain response and crack path in different deformation modes is demonstrated.