Analysis on tensile properties and influence factors of composite hybrid joints

Proper bolted or screw/bonded hybrid joint design can improve the structure efficiency. In order to solve the analysis and design problems that exist in screw/bonded hybrid composite joint structures, a 3D damage accumulation finite element analysis (FEA) model was established based on the software of ABAQUS. Non-linear properties of the adhesives and non-linear touch problems were included in this model. The analysis results of the tensile strength and damage propagation and failure of the joint structures agree with the test results. And the model effectiveness was proved. Then the influence factors such as the flange at the tip of the laminates, adhesive film thickness, adhesive toughness and contact surface friction coefficients on the joint tensile properties were studied. The results show that the flange at the laminate tip can reinforce the hybrid joint structures and improve their tensile strength. Adhesive with high toughness can improve the joint tensile strength and the film thickness almost has no effect on the strength. Higher friction coefficient between the screw pin and the hole surface can give greater joint tensile strength.