Reinforcing an aluminum/GFRP co-cured single lap joint using inter-adherend fiber

Methods to increase the strength of co-cured joints are highly sought after for metal/composite hybrid structures. The present study proposes a reinforcing method for aluminum/glass fiber-reinforced polymer co-cured composites using inter-adherend (IA) fiber that penetrates into the composite and holes in the metal adherend. The IA fiber performs as a bridge and suppresses crack propagation in the lap joints. Static and fatigue tensile tests were performed, and the displacement to failure and ultimate static strength were found to be significantly increased using the IA fiber without a decrease in the fatigue performance. The optimal tension force to the IA fiber realizes higher static tensile strength with lower scatter.