Experimental investigation on the cross-tensile properties of tubular rivet-reinforced joints

To decrease the exterior protrusion height and improve the tensile strength of the clinched joint, a rivet-reinforcing method was implemented on the clinched joint in this study. Solid rivets and tubular rivets with the wall thickness of 1.0 mm, 1.5 mm, and 2.0 mm were employed to conduct the rivet-reinforcing experiments on the clinched joints. Mechanical interlock structure measurements and mechanical properties tests were performed on the above-mentioned reinforced joints. The results show that the rivet-reinforcing technology can significantly increase the tensile strength and improve the mechanical behavior of the clinched joint. Compared with the NRJ joint (the reinforced joint with no rivet), the static tensile strength of TRJ-1.0 (the rivet-reinforced joint with the tubular rivet of 1 mm wall thickness), TRJ-1.5 (the rivet-reinforced joint with the tubular rivet of 1.5 mm wall thickness), TRJ-2.0 (the rivet-reinforced joint with the tubular rivet of 2 mm wall thickness), and SRJ joint (the rivet-reinforced joint with the solid rivet) is separately increased by 30.05%, 24.59%, 16.28%, and 7.19%. The TRJ-1.0 joint has the highest tensile strength (1489.57 N) among the five types of reinforced joints in the cross-lap-tensile test. The energy absorption capacity of the rivet-reinforced joints decreases as the wall thickness of the tubular rivet increases. Therefore, the TRJ-1.0 joint has the highest energy absorption that is 5.890 J, while the energy absorption of the SRJ joint is the lowest, which is 2.868 J. The TRJ-1.0 joint has the most excellent strength performance in the lightweight evaluation, which with a lightweight evaluation value of S 1.0 = 2.326 kN / g . However, the TRJ-1.5 joint has the most outstanding energy absorption performance in the aspect of lightweight evaluation, with a lightweight evaluation value of E 1.5 = 5.231 J / g . The experiment has proven that the clinched joints reinforced with 1 mm wall thickness tubular rivets have the best mechanical properties.