Evaluation of bonding strength and fracture criterion for aluminum alloy-woven composite adhesive joint based on cohesive zone model

In this paper, the bonding strength between aluminum alloy and woven composite joined by Araldite adhesive is evaluated. A fracture criterion for the joint subjected to mixed-mode loading is then proposed. For this work, specimens consisting of aluminum alloys adhered to woven composites by Araldite® Standard were fabricated and tested under normal and shear loadings by using the double-cantilever beam test and the shear-lap joint test, respectively. The fracture behavior of the adhesive joint was investigated by monitoring cracks formed at the adherend surfaces. The results indicate that cracks propagate into the woven composite bulk rather than into the aluminum alloy bulk. Furthermore, finite-element simulations of these tests suggest that the fracture behavior of adhesive joints is well described by the cohesive zone model. Bonding strengths under opening- and shearing-fracture modes are evaluated by comparing experimentally applied loads with simulated loads. This study reveals characteristics of the aluminum alloy-woven composite adhesive joint that differ from those of adhesive joints between similar adherends. Finally, a locus of fracture criterion for the adhesive joint based on the bonding strength of the joint is presented.