Self-Pierce Riveting of Three Thin Sheets of Aluminum Alloy A5052 and 980 MPa Steel

Abstract

Self-pierce riveting of three thin sheets of 980 MPa steel and 5052 aluminum alloy was performed to investigate the effect of sheet configuration on the deforming behaviors of the sheets and the rivet and joint strength. When the lower sheet was aluminum alloy, the joining range was relatively wide, i.e., the interlock hooking the rivet leg tended to be large. In the sheet configuration in which the upper and lower sheets were A5052 and the middle sheet was 980 MPa steel, the rivet leg spread out moderately and the joint without defects was obtained. In the lower 980 MPa steel sheet, fracture tended to occur due to the low ductility of the lower sheet, and the joining range was narrow with the small interlock although the three sheets were joined by an appropriate die shape. In joint strength of joined three sheets, fracture occurred in the lower-strength aluminum alloy sheet if interlocks of about 300 μm and 150 μm could be formed in the lower aluminum alloy sheet and 980 MPa steel sheet, respectively.

Triple joining of different sheets with self-pierce riveting method

“…Since the aluminium alloy sheet at the bottom can be deformed more easily, the rivet was able to move more easily in the sheet and reached a higher interlocking ratio. The results of Acira et al's studies also support this situation [20]. In addition, the tensile shear forces of these two combinations (AFA and FFA) are generally higher than the results obtained in the experiments.…”

“…Achira et al joined A5052 alloy and 980 MPa steel sheets by self-piercing riveting in different triple combinations. The aluminium alloy of the bottom sheet increases the interlock ratio and provides more successful joints [20]. Song et al used the self-piercing riveting method to join the sheets as a single-lap and butt-joint type.…”