Fatigue behavior of hybrid and bonded single lap joints made of composite material

Joining of composite materials can be performed with different techniques and, in particular, trough mechanical fasteners, bonding, hybrid solutions. In last years, hybrid (bolted/bonded) joints are attracting the interest of several companies and scientific community, since the use of both techniques permit to overcome some critical aspects connected to the separate usage of adhesive and bolts, i.e., negative effects of the environmental conditions on adhesive, localized stresses at the notch. This paper aims to improve the knowledge about the fatigue behavior of hybrid CFRP (Carbon Fiber Reinforced Polymer) joints. For the purpose, experimental fatigue and static tests are performed on hybrid and bonded joints and the results herein discussed. Results are post-processed with the main goal to highlight the benefits led to the hybrid technique with respect to the bonding one.