MULTIAXIAL LOW CYCLE FATIGUE LIFE PREDICTION MODEL BASED ON PLASTIC ENERGY

The mechanism of the multiaxial fatigue damage is analyzed and a new plastic energy-based approach for predicting multiaxial fatigue life is described. In the approach the fatigue damage parameter is defined as the plastic energy on the critical plane. Features of the critical plane are discussed and the calculation of the damage parameter is presented. Verification of the model is achieved by comparing the predictions obtained by using the new model with the experimental data of 304 stainless steel under different loading conditions. The results show that the fatigue damage parameter has definite physical meaning and the approach can be used under either proportional loading or nonproportional loading.