Analysis of the low temperature-dependent behaviour of a ductile adhesive under monotonic tensile/compression-shear loads
Résumé
Various models exist to describe the non-linear behaviour of an adhesive in an assembly, taking into account the two stress invariants, hydrostatic stress and von Mises equivalent stress, which can be explained by the nature of the adhesive, i.e., a polymer. The identification of the material parameters of such pressure-dependent constitutive models requires a large experimental database taking into account various tensile-shear loadings. Under quasi-static loadings at low temperature, for a given strain rate range, viscous effects can be neglected, but only a few experimental results are available to model the behaviour of an adhesive in a bonded assembly accurately under realistic loadings. Moreover, edge effects often have a large influence on the mechanical response. This paper presents the possibility of combining the use of a modified Arcan device, which strongly limits the influence of the stress concentrations, with a usual thermal chamber. Experimental results, underlining the temperature-dependent non-linear responses of an adhesive, are presented in the case of various tensile/compression-shear monotonic loadings for a temperature range between 20 °C and −60 °C. The analysis of experimental results, obtained in the load-displacement diagram, focuses herein on the modelling of the initial temperature-dependent yield surface; but such results are also useful for the development of the flow rules in the case of pressure-dependent models.