Application of a new model proposal for fatigue life prediction on notchesand key-seats

The aim of this paper is to introduce a new macro-mechanical model for fati gue life prediction, taking into consideration an elastic-plastic stress di stribution and the stress gradient evolution. Mainly based on the stress fi eld intensity approach, this new model tries to better take into account th e role of the most important factors influencing the fatigue failure proces s. A very brief review of some previous models facilitates the comparison b etween these approaches and fatigue test results obtained on notched specim ens with two different radii. A description of the stress field intensity m odel is then given, followed by the new model in more detail. In order to b etter verify the fatigue life prediction given by this method on another ki nd of notch geometry, a comparison between the method and test results on t he rotating bending of specimens with key-seats, is carried out. In all cas es, the fatigue life predictions obtained by use of this method, are in ver y good agreement with the respective test results. (C) 1999 Elsevier Scienc e Ltd. All rights reserved.