A SELF-PIERCING RIVET

摘要

A self -piercing rivet (10) for forming joints in stacked sheets of high or low strength, light alloy metals such as aluminium and magnesium. The rivet (10) comprises a head (11) and a substantially cylindrical shank (12) that is at least partially hollow so as to define a bore (13) that extends along at least part of its length. The outside diameter (D1) of the shank (12) is at least 6mm, the effective length of the rivet is at least 1.3 times the diameter of the shank and the bore (13) has a volume that is at least 38% of the effective solid volume of the rivet (10). The rivet geometry is such that it has enhanced column strength to withstand the high insertion forces required and a high bore volume to accommodate displaced sheet material.