Study on the influence of electric erosion on the early lubrication state of rolling bearings

Using a bearing test rig, the friction torque and outer ring temperature of 6204 deep groove ball bearings were measured under an electric field environment. Post-test analysis of the bearing surface was conducted using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS).

Additionally, the lubricant film thickness and friction coefficient under the electric field environment were measured using an optical elastohydrodynamic lubrication (EHL) film test rig. The results indicate that in the initial stages of electrical erosion, a direct current (DC) electric field leads to a reduction in film thickness and COF. Discharges within the lubricant film create electrical erosion pits on the bearing surface, inducing material transfer and oxide formation in the contact pairs.