Influence of edge distance on quality and static behaviour of self-piercing riveted aluminium joints

Self-piercing riveting is one of the main joining methods for construction of aluminium body structures in the automotive industry. In order to optimise vehicle mass it is desirable to use minimum flange widths, which has implications with respect to the rivet to sheet edge distance and consequently joint quality and strength. The influence of the rivet to sheet edge distance, referred as edge distance, on the quality and strength of self-piercing riveted joints was evaluated using standard aluminium alloy AA5754 through two groups of samples. For Group 1; the edge distance changed by varying rivet pitch, whilst the samples’ width was kept constant. For Group 2; the different edge distances were obtained by changing sample width, whilst the rivet pitch remained the same. The results showed that the edge distance affects joint quality by altering distortion levels and tearing resistance. The increase in edge distance led to an increase in both lap-shear and coach-peel strength; whilst rivet pitch and specimen width play a minor role in the strength trend. An optimum edge distance and a minimum edge distance with considerations on joint quality and strength are recommended.