Contact with coupled adhesion and friction: Computational framework, applications, and new insights

Contact involving soft materials often combines dry adhesion, sliding friction, and large deformations. At the local level, these three aspects have been simultaneously captured only in the theoretical framework proposed by Mergel et al. (2019) (arXiv:1803.00046). We here develop a corresponding, nonlinear finite element framework that captures 3D finite-strain contact of two deformable bodies. This framework includes the two models by Mergel et al. (2019), and is suitable to investigate sliding friction even under tensile normal loads. First, we investigate our finite element model in test cases covering both 2D and 3D, ranging from compliant tapes to structures with high stiffness, and including deformable-rigid and deformable-deformable contact. We then provide new results on the onset of sliding of smooth elastomer-glass interfaces, which couples nonlinear material behavior, adhesion, and large frictional stresses. Our simulations not only agree well with both experimental and theoretical findings, they also provide new insights into the current debate on the shear-induced reduction of the contact area in elastomeric contact.