Review on Damage and Failure in Adhesively Bonded Composite Joints: A Microscopic Aspect

Adhesively bonded joints offer numerous advantages for industrial applications. However, because damage and failure in adhesively bonded joints occur within thin adhesive layers between stiff adherends, experimental characterization and numerical simulation that account for microscopic phenomena are particularly challenging. For adhesively bonded composite joints, in particular, the interaction between adhesive and adherend damage must also be carefully considered. This review article mainly discusses and reviews the microscopic aspects of damage and failure in adhesively bonded composite joints for aerospace applications. Three main topics are addressed in this article. First, the peculiar deformation and damage behaviors of polymeric materials, including their dependence on stress triaxiality, are discussed. Second, the experimental characterization of deformation and damage in adhesive layers using advanced microscale inspection techniques is reviewed. Lastly, the modeling and numerical simulation of damage and failure processes, incorporating microscopic phenomena, are explored. The article concludes with a discussion of future perspectives.