Study of adhesive bonded joint failure in composite-metal joining

Currently, composites play an important role in the automotive industry where the weight reduction is a key of success due to its high strength to weight ratio. However, the replacement of metals with composites cannot be entirely archived, the joining between composite-metal is required. Bonding with adhesive is one of the most important methods in composite-metal joining. However, the accurate failure prediction of adhesive layers is still lacking due to the complicated state of stress at free-edges of specimens. The aim of this work is to investigate the failure behavior and analysis of acrylic adhesive which is particularly designed to provide superior bonding between composites and metals. Since an adhesive is generally a polymer, its failure depends on the hydro-static pressure. The chosen criterion needs to take into account this dependency. In this study, the Drucker-Prager failure criterion has been used. The parameters were characterized by tensile, compression and double lap shear tests. Then the FEM simulation was performed to predict a failure of single lap shear tests as a validation of model.