CONICET | Buscador de Institutos y Recursos Humanos

Undercuts affects fatigue strength of welded joints since it constitutes a notch at the weld toe. The analysis of the importance of undercuts demands accurate prediction of fatigue lifetime. Detrimental effects of undercuts are governed by stress concentration, which is characterized by its geometry (notch depth and root radius). Relationship between undercut geometry and fatigue strength of transversely stressed butt-welded joints was studied by means of a fracture mechanics approach and numerical simulations. Undercut depth proved to control fatigue behavior of sharp notches and demonstrated to be a limiting parameter that can be used conservatively in fatigue design of welded joints. Results of estimations are analyzed and compared with current recommendations, codes and standard tolerances.