Application of Acoustic Emission for Monitoring Fatigue Damage in CFRP-CFRP Adhesive Bonded Joints

Adhesive bonded joints are more and more applied in modern structures. However, production defects and particular operative conditions may cause local de-bonding and catastrophic failures. Structural Health Monitoring and Non-destructive Testing procedures are, then, needed for evaluating the integrity of adhesive bonded joints during service. In this research, an adhesive bonded single lap joint, whose adherends are manufactured using a carbon fiber reinforced polymer composite, was subjected to a constant amplitude fatigue test. During this test, the integrity and damage condition of the joint was continuously monitored by acoustic emission, while the test itself was periodically interrupted in order to carry out micro computed tomography of the specimen for investigating the real features of the damage. Results show that monitoring by acoustic emission, after suitable elaboration and filtering my means of pattern recognition algorithms, allows identifying and charactering effectively the development of fatigue damage in adhesive bonded joints.