Improved Generalized Strain Energy Damage Function Method for High Temperature Low Cycle Fatigue-creep

The generalized strain energy damage function(GSEDF) model for low cycle fatigue-creep(LCF-C) is investigated,and by using the inelastic strain energy as an LCF damage parameter,an improved GSEDF model is proposed for high temperature low cycle fatigue-creep life prediction of high temperature components,which modifies the energy parameter in GSEDF model and is more consistent with the actual engineering than the GSEDF model.The proposed model has the advantage of less parameters in the expression of this model,wide application and higher utilization efficiency of experimental data.Furthermore,this model not only considers the mechanism of loading waveform and hold time,but also the mean stress effects on LCF life.The predicted fatigue lives based on the proposed model are found in good agreement with reported experimental results of aircraft turbine disk alloys GH4133 at different temperatures and strain(stress) ratios.Compared with the GSEDF model,the SWT model,the plastic strain energy density method and the strain energy frequency modified approach,the proposed model is widely applicable and more precise in predicting the life of low cycle fatigue-creep interaction.