Theoretical and numerical aspects of the volumetric approach for fatigue life prediction in notched components

Abstract

Many macro-mechanical models for fatigue life prediction have been proposed. One of these methods is the ‘volumetric approach’. This paper is a complete investigation in theoretical base, intrinsic features, assumptions and its applicability for various notched components. The macro-mechanical behavior of notch roots and special notch root characteristics in a bi-logarithmic diagram for fatigue crack opening stress corresponding to distance in notch root gives pseudo-fracture mechanics behavior for fatigue cracks in notch roots for specific regions. The effective stress, effective plastic zone and relative stress gradient are determined by means of elastic–plastic finite element analysis. The fatigue failure estimations have very good agreement with the experimental results for various kinds of notch geometry.