Friction Characteristics of Microgrooved Bearings under Mixed Lubrication

In this paper, the friction characteristics of microgrooved bearings are examined experimentally and theoretically. The microgrooved bearings have an advantage of suppressing the oil film temperature rises under the heavy loaded conditions. Therefore, this type of bearings are effectively used for automotive engines, for example. However, with the trends of severe operating conditions using very low viscosity oils for the requirements of energy saving, the bearings are increasingly operated under the mixed lubrication conditions. To protect the bearing surface from damage such as seizure and fatigue, it is strongly needed to know the friction characteristics of microgrooved bearings operated under the mixed lubrication conditions. In the experiments, the bearing backside temperature, friction force, friction coefficient and bearing surface topography were measured by changing the applied unit load step by step, and the measured results were compared with the predicted results calculated by the mixed lubrication model. There were good agreements between them and the friction characteristics of microgrooved bearings were clarified experimentally and theoretically