Static and fatigue behavior of self-piercing riveted joints with two overlap areas

The tensile-shear self-piercing riveted (SPR) joints with Al-5052 with different overlap areas were prepared to conduct the static and fatigue test employing two fatigue loading frequency, for study the influence of overlap area and fatigue loading frequency on mechanical behavior of SPR joints. Test results indicated that with the increasing of overlap area, the static strength and ductility of joint could be improved, but the stability compromised. The static failure mechanism of SPR joint was that rivet was pulled out from the lower sheet. The overlap area and fatigue loading frequency had significant influence on fatigue life, and the effect of overlap area was prominent. For the all most fatigue load range, the narrow specimen with lower loading frequency showed favorable fatigue strength. Based on the lower loading frequency, the fatigue strength of wide specimens was about 1.89 times of that of the narrow specimens. The fatigue failure mechanism was the lower sheet fractured next to rivet shank almost and the upper sheet fractured around to the rivet head sporadically