Propagation Lifetime from the Surface and Internal Defects in the Ultra High Cycle Fatigue Regime
نویسنده
چکیده
Ultra High Cycle fatigue leads to a failure initiated in the bulk material of a material. Some results on the nodular cast iron are presented: initiation occurs from the defects, located at the surface or in the bulk. It has been shown that environment plays a major role that could explain the difference between fatigue lives, for the surface and internal initiation. The influence of the defect size and crack growth law is discussed and, the importance of fatigue crack initiation stage is revealed, in the ultra high cycle regime
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