In this study, we clarified relationship between the interfacial average stress and the non-dimensional intensity of stress singularity for aluminum bonded joints. In experiments, delamination tests were carried out by changing thickness of the adhesive layer, and the delamination force for each thickness of the adhesive layer was obtained. In addition, the intensity of stress singularity for each bonded joints model was computed by results of stress analysis based on the FEM using Akin singular element. Consequently, the relationship between the delamination force and the intensity of stress singularity could be obtained. However, this relation can't be directly applied to evaluate the delamination force, because the value of the order of singularity is different at each target problem. Therefore, in this study, the non-dimensional intensity of stress singularity was calculated based on applied force and characteristic length, i.e., width and thickness of adhesive layer, and the relationship between the interfacial average stress in delamination and the non-dimensional intensity of stress singularity was finally derived.
