A New Coated Self-Lubricating Spherical Plain Bearing with High Performance and Excellent Security

The low service performance and sudden failure characteristics of coated self-lubricating spherical plain bearings (SPBs) limit their engineering application prospects. In the current study, two new self-lubricating coatings types were applied to the bearing contact surfaces. The bearings were compared and investigated using life tests. Furthermore, the wear failure mechanism was investigated. The results show that self-lubricating coatings improved the service performance of the traditional bearings with manganese phosphate coating. Among them, double-sided coated bearings had the best service performance and life. More interestingly, the torque and temperature rise signal curves will show a notable signal downstage before the signal mutation stage. The large-area and complete mixed friction transfer film on the contact surfaces was the main reason for the signal downstage. Moreover, the failure mechanism changed from abrasive wear to adhesive wear and fatigue wear with the increment of load. This study results preliminarily verify the performance improvement of high-performance coatings and provide a theoretical reference for further breaking through the engineering application bottleneck of coated self-lubricating SPBs.