Study on Fatigue Life Prediction of Mechanical Components with Stochastic Cyclic Load Application

Abstract

Based on the nominal stress method for fatigue life prediction, the model for predicting the fatigue life of mechanical structures under random cyclic load is developed in this paper. The uncertainty of the cyclic loads applied on the mechanical structures is analyzed. With the number of load application as the life index, the fatigue life prediction models of mechanical structures under random cyclic load are developed with the probability weighted method and the Miner linear cumulated damage rule, when the relationships between fatigue life and stress can be expressed as the exponential function and the power function, respectively. Finally, the models proposed are used to predict the fatigue life of train axis.