Influence of riveting sequence/direction on distortion of steel and aluminum sheets

As a viable alternative to resistance spot welding, self-piercing riveting has been extensively applied to joining difficult-to-weld sheet metals such as aluminum alloys and dissimilar metal combinations. This investigation focuses on one important, yet often overlooked aspect of SPR applications, i.e., dimensional stability of components joined by SPR, which is an important consideration in product design and assembly. A number of riveting sequences, in combination with riveting directions, were tested on both aluminum and steel sheets, and their interaction with specimen width were studied. The distortion of a component joined by multiple self-piercing rivets was found to be minimal when the rivets are processed through alternating directions, or when the riveting process is constrained, such as by existing riveted joints.