Abstract: Clinching is widely applied because of its high-efficiency and low-consumption. Clinch-bonded hybrid joining emerged to improve the strength of clinching joint. The specimens of 1420 aluminum-lithium alloy homogeneity clinched joints and clinch-bonded hybrid joints were prepared in this study. Static strength and bearing capacity of two kinds of joints were measured by static tensile shear test. Fatigue properties of them were measured by dynamic fatigue test and the fatigue life curve was fitted by three parameter method. The fatigue fracture were observed in scanning electron microscope to analysis fatigue failure mechanism and characterize mechanical properties of different joints. Results show the static strength of the clinch-bonded joint was increased by 108.17% and load capacity increased by 169.63% compared with the clinched joint. For fatigue properties of two kinds of joints, neck fracture was presented in the short fatigue life. However, the fatigue fracture were carried out in different location in the long fatigue life, the clinched joint in the lower plate and the clinch-bonded hybrid joint in the clinched joint, and the fatigue life of the clinch-bonded hybrid joint was better than that of the clinched joint. The SEM analysis of fatigue fracture showed that two groups joint presented the mixed characteristics of ductile fracture and brittle fracture.
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