Spot joining of aluminium intensive car, truck and recreational vehicle bodies using self-pierce riveting (SPR) technology is well established with over 10 years of commercial application in the automotive industry [1]. SPR is a promising solid state joining technique for magnesium, especially for spot joining to dissimilar metals because the formation of brittle inter- metallic phases encountered in fusion joining such as resistance spot welding is avoided. The challenge however is to prevent cracking during SPR joining, especially when magnesium is placed on the bottom in the design of the joint.
This paper deals with progress made in SPR joining of magnesium using a laser to produce crack-free joints. Results are presented on the quasi-static tensile shear strength of various joints produced at cycle times of less than 5s.