Assessment of low cycle fatigue strength of notched components

In this paper, an attempt is made to assess low cycle fatigue (LCF) strength of notched components criteria, which are used in the practical design procedures for the fatigue life prediction. The Von Mises stress, as a proven in design practice parameter was used. The assessment based on both the finite element method analysis and on numerous experimental data obtained by LCF testing of two alloyed steels and two titanium alloys. Specimens of various shapes (cylinder, plate) with theoretical stress concentration factors ranging from 1.39 to 7.8 as well as smooth ones were used. The investigation shows that the stress concentration factor Kt predetermines stress or strain cycling in the concentration zone, and the cyclic life may be predicted by use of the Von Mises stress or strain, correspondingly.