An engineering model of spalling fatigue failure in rolling contact. II. The surface model

A model is advanced for explaining and predicting the incidence of rolling contact fatigue initiated at the contacting surfaces. The model includes fatigue initiating at (1)pre-existent surface discontinuities such as furrows and pits and (2) at the microgeometrical asperities on the surface. The model accounts for the dependence of endurance life on the number and severity of surface defects, the film parameter (the ratio of the lubricant film thickness to the surface roughness), and the slope angle of the microgeometrical asperities. In addition, influence factors are provided to account for lubricant-metal surface interactions. None of these were explicitly covered in the existing theory of rolling bearing fatigue life prediction.