Research on the fatigue resistance of weld ends

Abstract

Abstract Modern welded structures often contain weld ends due to increasing component complexity and economic motives. Under cyclic loading, crack initiation mainly occurs at those weld ends which makes them the failure critical location. So far, no detailed approach for the assessment of the fatigue life of weld ends has been added to known international or national guidelines. A new specimen type was developed at the Materials Testing Institute University of Stuttgart with which the fatigue resistance of weld ends of different welding procedures can be evaluated and compared. Tensile tests and fatigue tests on those new specimens show that the loading capacity is dependent on the welding procedure and the weld end point considered, i. e. weld start or weld end. In a sketched assessment approach, those results can be transferred to components in order to carry out a fatigue strength assessment or to enable the selection of a welding procedure. The assessment with the notch stress concept is preferred for the further development of the assessment approach.