Enhancement of lubricant replenishment for starved lubrication by laser-induced wettability gradient surface

This paper addresses the lubrication issues experienced by rolling element bearings operating under limited lubricant supply (LLS) or starvation conditions. A novel three-dimensional comb-tooth-groove (CTG) surface pattern is introduced to promote oil replenishment through unidirectional force. The transport of oil droplets on the CTG pattern is examined to evaluate this force, while groove length and depth are characterized as key factors influencing the surface force. More practically, the impact of CTG patterns on bearing lubrication under LLS conditions is assessed through experiments on bearings modified with CTG surface arrays. These modified bearings exhibit reduced torque and temperature rise, highlighting the significant advantages of CTG surfaces in enhancing bearing performance. © 2024 Elsevier Ltd.