An incremental contact model for hyperelastic solids with rough surfaces

Abstract

Abstract Hyperelastic materials like gels and rubbers have numerous applications in daily life and industrial production. However, most traditional contact models for rough solids do not include the hyperelastic deformation mechanism. This paper extends the linear-elastic incremental equivalent contact model to study the contact processes of hyperelastic rough solids. For any specific surface separation, the contact stiffness is determined by the total area and number of the contact patches, as well as the instantaneous tangent modulus. Analogous to buckle theory, we introduce the hyperelasticity of materials through employing the tangent modulus. By integrating the stiffness of contact spots, the normal contact force is then obtained. The load-area relation predicted by the present model exhibits consistency with finite element results even up to a contact area fraction of 90%. For hyperelastic solids with self-affine fractal rough surfaces, we investigate the effect of surface morphologies on contact behaviors. This research will be helpful for further studies about the lubrication, leakage, and wear of contact interfaces.