The Fatigue Limit of Spot-Welded Lap Joints

Spot welded lap joints are quite common in the body and in the chassis of cars, although their low fatigue strength is well known. Meanwhile a procedure to correlate the geometry of the joint to the design fatigue strength is not yet available in the literature. Aim of this paper is to find a correlation between fatigue strength and geometry condidering both low carbon and HSLA steel joints.

Experimental fatigue data available in the literature have been reanalyzed using an unified scatter band approach and the check has been extended to different geometries. On the basis of the obtained results suggestions are given for improving the fatigue strength of the joints.