Effect of lubrication groove characteristics on the tribological performance of self-lubricating thrust roller bearings

Purpose This study aims to develop a novel self-lubricating thrust roller bearing and analyze its tribological behavior under various groove characteristics in lubricant-free environments, based on the bearing’s motion characteristics. Design/methodology/approach The groove characteristics, including the groove surface area relative to the friction region, the angle between the groove’s lubrication direction and the roller’s axial rotation and groove depth, were investigated. Grooves were created on the bearing shaft washer using an optical fiber laser marking machine, and solid self-lubricating materials were applied via scraping. Tribological performance and surface morphology were analyzed using a friction-wear test rig and a three-dimensional noncontact profilometer. The lubrication mechanisms of the novel thrust roller bearing were then examined under varying groove characteristics. Findings Thrust roller bearings with lubrication grooves demonstrated superior tribological performance, significantly reducing wear. The optimal configuration, with a 10% groove area, 45° groove orientation and 320 µm depth, resulted in the lowest wear, friction coefficient (0.002), wear loss (4.8 mg) and temperature (30.67°C). Compared to bearings without grooves, coefficient of friction decreased by 92.59%, wear loss dropped by 93.15% and temperature reduced by 56.94%. Originality/value This study introduces a novel design for a self-lubricating thrust roller bearing, which enables self-lubrication in environments without traditional lubricants. A comprehensive examination of its surface characteristics, lubrication mechanisms and tribological behavior has been conducted. This research provides valuable insights for the study and application of thrust roller bearings. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2024-0460/