Experimental research on the compressed joints with different geometrical parameters

In recent years, mechanical clinching has been widely used to join aluminium alloy sheets to build the automotive body. The high protrusion on the joint may limit the use of the mechanical clinching in the visible places. In order to get a lower protrusion, a compressing method was investigated in this work. Clinched joints with different geometrical parameters were used to conduct the experiments. AL5052 was taken as the material of the sheets. The protrusion of the clinched joint was compressed by two flat dies. A rivet placed in the pit of the clinched joint was used to control the metal flow in the compressing process. The top die moved downward to compress the protrusion, and the bottom die was fixed. The study shows that the tension-shearing strength and cross-tensile strength can be increased by the compressing method. The compressing method can increase the tension-shearing strength and cross-tensile strength by increasing the neck thickness. The compressed joint has larger neck thickness and lower protrusion than the clinched joint. Neck fracture mode is the main failure mode of the joints. The energy absorption can also be increased after the compressing process.