Abstract
The fatigue properties of arc welded lap joints using joggle-shaped 980MPa-grade steel sheets were studied in a plane bending fatigue test. The fatigue strength of the joggled lap joints was superior to that of the conventional lap joints. The influences of joint geometry, residual stress, and hardness near the welds on the fatigue strength of the joints were investigated. It was found that the average values of flank angles and curvature radii at the weld toe of the joggled lap joints were greater than those of the conventional lap joints. Furthermore, histograms of flank angle and curvature radius indicated that the joggled lap joints had lower probability of crack initiation than that of the conventional lap joints in the low load stress region. Therefore, the fatigue strength of the joggled lap joints were considered to be improved.
