Yield Behaviour of Rubber-Modified Epoxy Adhesives under Multiaxial Stress Conditions: Effect of Plastic Deformability of the Matrix Phase

Abstract

In a previous study, the yield stress in the adhesive layer of scarf and torsional butt joints with a rubber-modified adhesive was measured, and the results agreed with those calculated by a finite element method, where Gurson's constitutive equations were applied to the adhesive layer. In this study, to investigate the effect of plastic deformability of the matrix phase on the yielding behaviour of rubber-modified epoxy adhesives, the yield behaviour was investigated by using scarf and torsional butt joints, where a reactive diluent was used to vary the plastic deformability of the matrix phase. The applicability of Gurson's model was examined in terms of the yield stresses calculated by a finite element method with a variety of the model parameters. As a result, it is confirmed that the yield stresses of the rubber-modified adhesives with different matrix phases can be approximately estimated by Gurson's model, and the model parameter's agreement with the experimental data increases with increasing the plastic deformability of the matrix phase.