Affiliation:
1. Fraunhofer-Institute
2. Technical University of Braunschweig
3. Hamburg University of Technology
Abstract
Some recently developed variants of local concepts for assessing the fatigue strength and
structural durability of welded joints are reviewed. These comprise structural stress, notch stress or
strain and fracture mechanics concepts. New variants of the structural stress concept are Dong’s
gradient stress approach and Xiao-Yamada’s ‘one millimetre stress’ approach. FE meshing rules
have been developed for welded joints in thin sheet structures. The concept of fictitious notch
rounding is now better substantiated for aluminium alloys. The small-size notch concept is
applicable to thin sheet lap joints. The new notch stress intensity factor concept is based on the
singular stresses at the sharp weld toe notch. Advanced fracture mechanics concepts combine crack
initiation at the seam weld root or nugget edge and crack propagation over the plate thickness
resulting in endurable FK values as function of cycles per unit thickness, N/t.
Publisher
Trans Tech Publications, Ltd.
Subject
Mechanical Engineering,Mechanics of Materials,General Materials Science
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