Impact evaluation of rolling contact fatigue life models

Abstract

Since the accurate prediction of fatigue life has a significant value, many researchers have attempted to develop a reliable fatigue life model. Recently, rolling contact fatigue life models incorporating machining impact were developed. These models have contributed to a significant improvement in prediction accuracy as compared with earlier models, thus representing a major step forward in the modeling effort. This paper compares the prediction accuracy of these models with that of the prediction method in International Standards. When a is set to 0.25, the observed improvement of prediction accuracy as measured by variance of prediction errors due to these models over that due to prediction method in International Standards is statistically significant. Impact analyses of such improvement are conducted to illustrate its value. It is further noted that while difference was observed between the variance of prediction errors due to the crack initiation life model based on a dislocation model and that due to the crack initiation life model based on a local stress-life curve, the observed difference is not statistically significant.