AbstractThe effect of an electric field applied between rubbing surfaces on friction and wear characteristics was examined using a ballon‐disc testing apparatus under different lubrication conditions. The lubrication conditions were changed by changing the viscosity of the lubricants. By applying an electric field between the rubbing surfaces, the oxidation of the rubbing surface at the anode side is enhanced, and suppressed on the cathode side surface. The oxide film formed on the anode surface being harder than the bulk steel, the rubbing surface at the anode side was little worn, but that at the cathode side was abrasively worn. This wear characteristic could be utilised to attain favourable running‐in. The application of an electric field, however, is considered to promote the breakdown of any EHL film formed. Therefore the effect of the application of an electric field between rubbing surfaces is influenced by the lubrication condition that is being tes