Using a bonded solid film lubricant to prevent fretting wear in the axle journal bearings of rail vehicles

Fretting degrades the inboard inner ring and the backing ring contact surfaces of axle journal roller bearings used in railway applications. This study attempts to prevent fretting wear between them as well as fretting wear particles from entering the axle bearing interior without introducing new bearing components. It has been reported that coating metallic surfaces with bonded solid film lubricants improves lubricity and wear resistance while reducing fretting wear. To evaluate the impact on fretting wear prevention, a full-size railway axle bearing that was coated a backing ring side face with a bonded solid film lubricant was rotated. The findings demonstrate that applying the bonded solid film lubricant to the backing ring side face does not prevent the axle bearings from fretting. The surface temperature probably exceeds the heat-resistant temperature of the solid film lubricant because of the fretting friction.