Low cycle fatigue life prediction for GH4133 at 550° based on power-exponent function

The low cycle fatigue tests of gh4133 superalloy are carried out under total axial strain at 550°. the relationships of cyclic stress-strain and strain-life are analyzed. the low cycle fatigue test data of gh4133 superalloy are processed by using the manson-coffin method. when experimental data is processed,the relationship between plastic strain and failure reverse number presents nonlinearity in the double logarithmic coordinates. therefore,there must be some prediction error,when using the manson-coffin method. in order to solve the problem,a new method based on the power-exponent function is developed. the results of life prediction are given by using a new method at the same time. the results showed that the two methods chosen were able to provide a reasonable life prediction result for the gh4133 superalloy with prediction accuracy within ± 1.5 times the scatter band. in order to verify the applicability of the new method,the low cycle fatigue life of the seven materials is predicted. the results of life prediction showed new method gave better results with the smaller scatter band and standard deviation than manson-coffin method. thus the life prediction capability of the proposed method proves to be more effective and accurate than the manson-coffin method.