Fatigue strength of austenitic butt welded joints under thermomechanical loading conditions

Butt welded joints made of austenitic steel are often a part of components for power plants or for chemical equipment constructions. Thereby, the components are subjected to cyclic mechanical and thermal loadings. Especially caused by high ranges in temperature loading, high elastic-plastic strain ranges are the result. Differences in plastic deformation behavior of base and weld material, led to a metallurgical notch, which may govern fatigue failure. During the accompanying numerical investigations, a model for the consideration of the metallurgical notch has been developed.