EngineeringMaterials EngineeringMaterials ScienceSurface EngineeringTransportation EngineeringTribologyBearing Surface MaterialsRail TransportRail TransportationRoad TransportSliding ContactWear-resistant MaterialsFrictional AdhesionSurface FrictionSurface Layer IntegrityWearWheel-rail Interaction
The various studies and contributions are drawn into a coherent statement of how wheel/rail friction varies. Surveys of a number of track sites have identified the contaminants present in the wheel/rail interface, and measurements have been made of the adhesion which is experienced by railway traffic. A principal contaminant is a surface active oily fluid spread by the passage of wheels which forms a bonded surface layer on the wear band. A simple relationship has been found between the amount present on the surface and the resulting friction.