Experimental Study on the Mechanical Behavior of Flat‐Joggle‐Flat Joints Bonded With GNP/CNT Modified Adhesives

The present work focused on improving the mechanical and vibrational properties of Flat‐Joggle‐Flat (FJF) adhesive‐bonded Carbon Fiber‐Reinforced Polymer (CFRP) joints by the influence of Graphene Nanoparticles (GNPs) and Carbon Nanotubes (CNTs) as adhesives. The CFRP laminates were manufactured using the hand layup technique with vacuum assistance, with a fiber orientation of [0/45/90/45/0] s . The modified adhesives were prepared using sonication with weight ratios of 0%, 0.25%, 0.5%, 0.75%, and 1%. The experiment results revealed that the maximum shear strength is 29.23 MPa at GNP (0.75%) and 82.04 MPa at CNT (0.5%), compared to the neat epoxy and Glass Chopped Fiber (GCF). The maximum natural frequency is 863.61 Hz at CNT (0.5%), 43% higher than neat epoxy, 44% higher than GCF, and 15% higher than GNP (0.75%). The failure modes results revealed that the neat, GCF, GNP, and CNT adhesive FJF joints are cohesive failures. Meanwhile, a cohesive failure has occurred due to the strong interfacial bonding strength between the adherends and the adhesive in CFRP composite joints. Moreover, the influence of CNT‐modified adhesives on FJF joints exhibits more excellent mechanical and vibrational properties than GNP adhesives on FJF joints.