Taguchi sensitivity analysis of damage parameters for predicting the damage Mechanism of 9Cr steel under low-cycle fatigue test

ABSTRACT Numerical investigations of low‐cycle fatigue damage parameters of a 9Cr steel have been studied and compared with the previous results in order to understand the effect of the damage parameters on predicting the damage development of the material. Using the nonlinear kinematic softening criterion, the Chaboche constitutive equation is combined with the hysteresis total stress–strain energy concept to implement damage initiation and evolution; the remaining life of the specimen can be predicted. In this paper, the cyclic softening model in conjunction with the progressive damage evolution model successfully predicted the failure times of the experimental tests. By using a novel sensitivity analysis of the damage parameters c1, c2, c3 and c4 based on the Taguchi method, the highest parameter effect has been determined.