Effect of abrasive contaminants on scuffing

Four-ball machine tests have been performed to study the effect on scuffing of fine silica abrasive particles contained in the lubricant. The boundary lubrication zone that sets in after seizure recovery has been utilized in the study. The particles are found to increase abrasive wear but reduce adhesive wear and to cause scuffing at less severe conditions that with clean oil by contributing to frictional heating. When the heat generated cannot be dissipated from the contact zone the contact temperature is found to increase and lubricant desorption causes scuffing.