Free-Edge Stress Singularity of Bonded Dissimilar Materials with an Interlayer

Abstract

Free-edge stress singularity usually prevails at the edge of the interface of the bonded dissimilar materials. When two materials are bonded by using an adhesive, an interlayer develops between two materials. An interlayer may inserted between two materials to defuse the residual stress due to the difference in the coefficients of thermal expansion. In this study, to investigate the effect of the interlayer on the free-edge stress singularity of the bonded dissimilar materials with an interlayer, the stress distributions on the interface were examined numerically and theoretically. Relation between the free-edge stress singularity of the bonded dissimilar materials with and without an interlayer was investigated by using the boundary element method. It was found that the effect of the interlayer on the stress distribution was limited within a small area of the order of the interlayer thickness. Stress distributions near the edge of the interface were controlled by the free-edge stress singularity of the bonded dissimilar materials without an interlayer.