Intensity of singular stress field for three-dimensional butt joint to evaluate the adhesive strength

Abstract

Adhesive joints are extensively used in various manufacturing processes in different industrial sectors because of its high fatigue resistance. Different materials properties cause the singular stress field, whose intensity is depending on the adhesive joint geometry. Our previous studies show that debonding strength can be expressed as a constant value of the critical intensity of singular stress field (ISSF) by using two-dimensional butt joint models. By considering real specimen geometry, in this paper, the ISSFs on the interface outer edges of three-dimensional butt joints are analysed by varying the adhesive thicknesses. A mesh-independent technique combined with three-dimensional finite element method (FEM) is shown to evaluate the ISSF. The ISSF distributions on the interface outer edges are analysed in comparison with the previous two-dimensional results. It is found that the critical ISSF considered 3D geometry is almost constant independent of the adhesive thickness.