Energy-based damage model incorporating failure cycle and load ratio effects for very low cycle fatigue crack growth simulation

Abstract

An energy-based damage model for simulating very low cycle fatigue (VLCF) crack growth is proposed to improve the prediction accuracy of our previous model. Modifications are made to explicitly include the terms related to failure cycle and load ratio. The parameters related to these terms are determined from mean fatigue life model of the material. The proposed damage model is validated by comparing with through-wall cracked pipe test data for Type 316 stainless steel. Predicted failure cycles are very close to experimental data, improving the prediction accuracy of our previous model. Comparison of fracture surfaces also shows good agreement.