Multiaxial fatigue limit criterion for defective materials

The objective of this paper is to quantify the influence of defect on the fatigue limit. Elastic-plastic simulations are conducted to determine the stress distribution around defects for different geometries and different loading. It is shown that a relevant mechanical parameter governing the fatigue limit for defect material could be the gradient of the hydrostatic stress. A multiaxial fatigue criterion is identified with three parameters and validated for different metallic materials under multiaxial conditions. Results are good and show that the gradient of the hydrostatic stress is a good parameter to characterise the influence of a defect on the fatigue behaviour. (c) 2005 Elsevier Ltd. All rights reserved.