Identification of mesoscopic fault of full ceramic ball bearings based on strain energy theory

The traditional steel bearing outer ring dynamics model is unable to describe the issue of sub-millimeter or even millimeter-scale mesoscopic flaws inside the outer ring of complete ceramic ball bearings. Based on the strain energy theory, a dynamic model is established for the subsurface mesoscopic defects of the outer ring of full ceramic ball bearings, and the influence of different defect depths on the running state of the outer ring of full ceramic ball bearings is investigated at the scale of mesoscopic defects. Through simulation, it is confirmed that when a mesoscopic defect exists on the subsurface of the outer ring of the bearing. There is a corresponding characteristic frequency near the intermediate frequency of the frequency domain signal, and the degree of defect evolution is determined by the ratio of the maximum positive value of its empirical mode decomposition (EMD) third-order component amplitude to its corresponding peak value of the intermediate frequency. Finally, the effectiveness of the constructed model is verified through experiments. Finally, the validity of the proposed dynamics model and simulation results is verified by experiments. The established model makes it possible to determine the degree of defect evolution and if sub-surface mesoscopic defects are present in the outer rings of complete ceramic ball bearings. The established model provides a new idea for the defect diagnosis of full ceramic ball bearings and a theoretical reference for the safe and stable operation of full ceramic bearing rotor systems.