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Microplastic deformation associated with rough surface and dents are found to generate tensile residual stress, which can be a source of surface fatigue. Both pre-existing hoop stress and friction-induced lateral normal stress parallel to surface are found to have an effect on the plastic strains and tensile residual stress. This finding can possibly explain many reported experimental observations that in rolling/sliding contact, the slower surface is more susceptible to surface fatigue than the faster mating surface. Micropitting probability and wear volume loss can be formulated based on Mode I crack growth process using the tensile residual stress as the fatigue criterion.

A close examination has been made on the result of experimental research on surface fatigue in the low Lambda regimes. These experiments consist of two kinds. One is the endurance test of needle bearings, ball bearings and roller bearings with different surface and lubrication conditions. The other is the test with disk machines to observe peeling (or micropitting). The study shows that the Lambda ratio is not the only parameter which affects the surface fatigue of bearings. In most cases, the life ratio depends more strongly on the composite rms surface roughness than on film thickness. Thus, in addition to the Lambda ratio, the effects of asperity height/tip radius ratio, nominal contact pressure, mean separation, lubricant inlet starvation, surface defect, hardness and the compressive residual (or tensile hoop) stress on surface fatigue, should be taken into account.

This paper describes the methodology and some computer-aided procedures for analyzing the contact of roller and a drawn cup bearing ring inside a housing of material of low tensile strength. The analysis can be used to predict the onset of plastic yielding in the housing. It also discusses the role of stresses arising from the press fit between the cup and the housing in preventing the relative slippage at the cup/housing interface and fretting corrosion. Illustrative examples are shown for a heavy duty drawn cup bearing with aluminum housing for a multitude of loads and cup thicknesses.