Effect of nanostructured reinforcement of adhesive on thermal cycling performance of a single-lap joint with composite adherends

Nanostructure of adhesive increased the failure load of bonded joints. Adhesively bonded joints are often exposed to alternating warm and cold temperatures in many applications. Hence investigation of their thermal cycle performance is very important. In the present study, the tensile strength of adhesively bonded single lap composite joints (SLCJs) was experimentally investigated under ambient temperature and thermal cycling conditions. In the study, carbon fiber fabric reinforced (CFFR) composites (0/90 degrees) with Plain Weave (PW) were used as the adherend; DP460 tough and DP125 flexible adhesive types were used as the adhesive and 1 wt% Graphene-COOH, Carbon Nanotube-COOH and Fullerene C60 were used as the nanostructures. Six different thermal cycles were applied to SLCJs and their tensile failure loads and failure surfaces were investigated. As a result, when the joints obtained through nanostructure non-reinforced adhesives are exposed to thermal cycle, a significant decrease appears in the failure load of the joint. Yet, adding nanostructure to the adhesive enhances the thermal cycle performance of the joint. This enhancement in the thermal cycle resistance changes depending on the structural features of the adhesive, the type of nanostructure and thermal cycle condition.