Elastic–plastic cylindrical rolling contact fatigue mechanism evolution and life prediction considering random surface topography

This paper proposes a semi-analytical fatigue life prediction method for the evolution of elastic–plastic cylindrical rolling contact fatigue mechanism under random surface topography, and reveals the evolution process of three contact fatigue mechanisms under high load conditions: micro-pitting, surface-originated pitting (SOP), and subsurface-originated spalling (SOS). Firstly, an elastic–plastic line contact model of random rough surface is proposed to analyze the contact condition between rolling elements considering random surface topography. Subsequently, a contact pressure spatial distribution model of rough surface is established, which can fully reflect the variation law of pressure distribution in the elastic–plastic stage. Finally, a semi-analytical life prediction (SALP) method is developed by combining the newly proposed analytical model with finite element method to illustrate the evolution process of the contact fatigue mechanism. The prediction accuracy of the SALP method is verified by comparing the results with those of the finite element method. Furthermore, the influence of random surface topography parameters (root mean square of roughness δ, correlation length λ) on contact fatigue life is further discussed, which helps to provide theoretical support for good surface process control for high-load rolling elements.