A MODIFIED METHOD OF VON MISES STRESS-BASED MWCM FOR FATIGUE-LIFE PREDICTION UNDER FULLY-REVERSED AXIAL-TORSION PROPORTIONAL LOADS

摘要

In this paper, based on the Modified Wohler Curve Method (MWCM). a novel multi-axial stress-invariant-based method is proposed. It has the ability to reduce the error produced by the deviation of the multi-axial parameter, which is an obvious influencing factor on the prediction accuracy. The new method introduces a ratio parameter to turn the von Mises stress into a new equivalent stress for fatigue assessments. An empirical hypothesis is taken as the starting point, and the iterative method is adopted to calculate the parameter more accurately. The present method was systematically validated with a large number of fatigue tests. It can be shown that, overall, the accuracy of the modified method has a certain degree of improvement compared to the original ones.