Numerical study on fatigue crack propagation behaviors in lubricated rolling contact

The surface-initiated Rolling Contact Fatigue (RCF) including pitting and micro-pitting is one of the key issues affecting the reliability of tribological components such as gears and bearings used in various devices. In this work, a surface-initiated crack Finite Element (FE) model which considers the effect of lubricant on crack faces was developed to investigate surface-initiated RCF using an automatic crack propagating Python script. Different lubricating states, initial crack parameters and loading conditions were simulated to analyze the evolution of crack propagation and the Stress Intensity Factors (SIFs). The RCF crack propagation path and life were predicted by employing the Maximum Tangential Stress (MTS) criterion coupled with the Paris's law. A typical RCF failure is predicted in the numerical simulation. Results reveal that the lubricating pressurization dominates the surface-initiated RCF. In addition, the initial crack angle has a significant effect on the RCF crack propagation path and the fatigue life. (c) 2021 The Authors. Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://creativecommons. org/licenses/by-nc-nd/4.0/).