Strain energy based fatigue model for notched part subjected to multiaxial loading

Abstract

In this study, a new fatigue assessment model is developed for high cycle fatigue of metals under multiaxial proportional loading. The proposed model uses readily available material properties and contains no parameters depending on geometry or loading conditions. It is applicable to parts containing a notch or locally high stressed regions. The effects of loading conditions and geometry are taken into consideration via the use of equivalent strain energy density parameter introduced in this study. Its numerical value depends on the strain state within the part obtained through finite element analysis. The predictions of the proposed fatigue model are compared with the results of two experimental studies conducted on specimens with different notch geometries, fillet and hole, and on two different steel materials; one was a carbon steel, the other was a stainless steel. In the experiments, different types of multiaxial loads were applied; one was bending combined with torsion, the other was axial load combined with torsion. For these different conditions, the model predictions and the experimental results correlate quite well.