Evaluation of the Fatemi-Socie damage parameter for the fatigue life calculation with application of the Chaboche plasticity model

This paper presents an approach to the evaluation of the Fatemi-Socie parameter applied to the lifetime calculation of specimens made of CuZn37 brass. In particular, two factors affecting the calculated fatigue lives are analysed: (i) the influence of stresses calculated by applying the Chaboche plasticity model on the computed lifetime and (ii) the influence of a variability of parameter k of material sensitivity to normal stress on the calculated lifetime. The novelty of the presented research is associated with the fatigue life calculation according to the Fatemi-Socie model with the introduced k dependence accounting for the lifetime. Underestimation of the calculated stresses results in the higher calculated fatigue lives but with acceptable scatter band. The parameter of material sensitivity to normal stress for the CuZn37 brass varies insignificantly having little impact on the calculated fatigue lives.