Failure Analysis on Wear of Self-Lubricating Spherical Plain Bearings

The ceramic coating fracture phenonema appeared at the inner ring spherical surface of a self-lubricating spherical plain bearing used for a machine after using for 390 h. By means of macroscopic analysis, chemical composition analysis, scanning electron microscope and energy spectrum analysis and so on, the wear reasons of the bearing was analyzed. The results show that the self-lubricating spherical plain bearing had greater stress on one side, serious wear on this side of the bearing and concentrated force, which had exceeded the normal working condition, led to rapid wear and tear of ceramic coating at the inner ring spherical surface and liner in inner spheral surface of outer ring. In addition, the adhesion between ceramic coating near the end of the bearing and substrate was weak and easy to peeling, which can also led to wear and tear failure of the bearing.