On Modelling the Non-linear Behaviour of Thin Adhesive Films in Bonded Assemblies With Interface Elements

This paper presents the development of a numerical model for an adhesive in an assembly, and compares results with experiments obtained from a modified Arcan fixture. The use of joint type elements ( or interface elements) allows reducing the numerical cost of simulating adhesively-bonded assemblies. Under an elastic load, a non-uniform stress field is observed in the adhesive for the Arcan test and an inverse technique using simplified strategies has been developed to characterize the adhesive behaviour with a low-numerical cost. The study of monotonic radial loadings for a given displacement rate allows obtaining the elastic yield envelope in the normal stress-shear stress plane and pointing out the higher strength under a compressionshear mixed loading, compared to a tension-shear one. Moreover, the analysis of the adhesive deformations for tension-shear loadings shows larger displacements in shear than in peel. These effects must be considered in the numerical models. Besides, modelling of the viscoplastic behaviour of the adhesive in an assembly is proposed for a wide range of deformation rates under pure shear loadings. Numerical simulations show the usefulness of joint type elements, compared to traditional continuum elements in order to model the non-linear behaviour of the adhesive in bonded assemblies. (C) Koninklijke Brill NV, Leiden, 2008