Branched crack growth behavior of mixed-mode fatigue for an austenitic 304L steel

Experiments on mixed-mode fatigue crack initiation and propagation in an au stenitic stainless steel 304L were carried out using a circular ring specim en containing a V-notch on the internal radius. The branched crack behavior was experimentally investigated with respect to the direction of the incli ned loading and the stress distribution near the notch root or crack tip, e specially, for the second and third branched cracks. The behavior of the cr ack initiating from the notch root under the mixed-mode condition is identi fied well by the maximum tangential stress criterion. The energy release ra te criterion can be used to simulate the path of the branched cracks initia ting from the parent crack. Optical microscope observation was performed to examine the microstructure of the material for the tested specimens and al l crack growth was typically transgranular mode. (C) 2000 Elsevier Science Ltd. All rights reserved.