Nonlinear Vibration Analysis of Full-Ceramic Angular Contact Ball Bearings considering Cage Cracks

Full-ceramic angular contact ball bearings (FCACBBs) have become essential components in extreme operating environments due to their exceptional mechanical properties, including superior hardness, thermal stability, and corrosion resistance. However, cage cracks generated during operation may induce nonlinear vibrations and eventual bearing failure. To investigate the nonlinear vibration response of FCACBBs induced by cage cracks, an enhanced equivalent stiffness model for cracks is established, which accounts for the influence of cage crack geometry on structural stiffness. With parametric sensitivity analysis revealing that crack depth significantly reduces structural stiffness by 81.4%, followed by crack angle at 60%. Furthermore, considering the influence of fluidthermal multi-physics field coupling, we aim to reveal the interaction mechanism between oil-gas distribution and thermal deformation in the crack region. The proposed model is then integrated into the FCACBB dynamic system to elucidate the coupled effects of rotational speed and crack depth on vibration signatures. Ultimately, FCACBB cage crack failure experiments are conducted. The results demonstrate that cage cracks induce increased vibration amplitude of the system. The time-domain waveform exhibits periodic impacts with distinct repetitive patterns, while characteristic frequency components associated with cage dynamics emerge in the frequency spectrum. By comparing the simulation results with experimental data, the maximum average relative error is 6.51% under different rotational speed conditions, which verifies the accuracy of the proposed model. The findings of this study provide valuable insights into the dynamic characteristics and mechanisms associated with crack propagation in the FCACBB cage.