2020 Volume 76 Issue 2 Pages I_143-I_152
Generally, it is considered that fatigue life can be divided into two separate contributions: the crack initiation life and crack propagation life. Recent years, the authors studied on a method which predicts the fatigue crack initiation life by using local strain approach and extended to the assessment method of crack propagation life handled as continuous behavior of crack initiation life. The aim of this paper is to introduce a new method for fatigue crack initiation and propagation life prediction of a non-load carrying fillet joint using an unconventional elasto-plasticity model called the Fatigue SS Model (hereafter, FSS model). The FSS model is based on the Subloading Surface theory, which was enriched by including the elastic boundary and cyclic damage concepts for the description of strain softening behavior within macroscopically elastic stress state. The FSS model was used to investigate the inelastic response of the material under different cyclic loading conditions. In this study, finite element analysis was conducted to assess the fatigue crack initiation life and subsequently crack propagation life by extending the assessment method for fatigue crack initiation life of a non-load carrying welded fillet joint by considering a cyclic plasticity accumulation during fatigue loading.
