Abstract：Experimental methods and finite element are used to study the failure mechanism of mechanical joints and adhesive-bolt hybrid joints. The load-displacement curve is analyzed by tensile-shear test, and the microstructure of the section is analyzed combining the stress distribution of the finite element simulation results. The results show that the perforated carbon fiber tow of the bolted joint structure is deformed by the bolt pressing force, which is passed to the resin matrix, so the fiber is subjected to buckle deformation, and the resin matrix is squeezed into a cluster by a short bundle of fibers that are uniformly distributed. Therefore the formed weak structure is due to uneven structure. Adhesive-bolt hybrid joints exhibits tensile fracture failure, the carbon fiber tow at the fracture is pulled out from the epoxy resin matrix under tensile-shearing and damages the fracture, and the direction of the tow is disorderly arranged. The resin matrix attached to the fiber changes to be agglomerated, and the joint structure fractures after reaching the ultimate load. And the adhesive between the sheets has a retarding effect on the destruction of the fibers after the redistribution of the load. Factors such as material strength, bolt strength, adhesive strength and bolt width to diameter ratio will be factors that affect the failure of the joint structure.
2020, 
