Numerical procedure for predicting the rolling contact fatigue crack initiation

A computational numerical model for contact fatigue damage analysis of mechanical elements is presented in this paper. The computational approach is based on continuum mechanics, where a homogenous and elastic material model is assumed in the framework of the finite element method analysis. Cyclic contact loading conditions are simulated with moving Hertzian contact pressure. The time-depending loading cycles are defined for each observed material point on and under the contact area. Furthermore, the influence of friction upon rolling-sliding contact loading cycles is analysed in detail, using Coulomb's friction law. The model for prediction of the number of loading cycles, required for initial fatigue damages to appear, is based on Coffin-Manson relations between deformations and loading cycles, and includes characteristic material fatigue parameters. As a general example, the model is used to analyse a fundamental contact problem of a cylinder and flat surface, which is usually a substitutional model for analysing real mechanical problems. However, the results concerning the identification of critical material points and the number of loading, cycles, required for initial fatigue damages to appear at those points, are the main purpose of the presented study. (C) 2003 Elsevier Science Ltd. All rights reserved.