Influence of displacement excitation and thermal deformation coupled waviness on slipping and vibration characteristics of full ceramic bearing

To investigate the effect of waviness on the slippage and vibration characteristics of the full ceramic bearing， displacement excitation and thermal deformation are coupled to propose the dynamic waviness model. The Hertz contact theory and time-varying displacement excitation are combined to obtain the calculation method of time-varying contact stiffness coefficient， and the stiffness coefficient is analyzed in detail. The effects of time-varying contact stiffness coefficient and time-varying displacement excitation are also taken into account to model the slipping dynamic of the full ceramic bearing. The effects of rotational speed and waviness on the slippage and nonlinear vibration characteristics of the full ceramic bearing are analyzed. The results show that an increase in rotational speed， waviness amplitude and wave number all lead to an enlarged contact stiffness coefficient between the ball and the raceway. The contact stiffness coefficient is more sensitive to changes in wave number. The increase in rotational speed can exacerbate slippage. Both the increase in waviness amplitude and wave number can have the effect of inhibiting slippage. However， the waviness amplitude and wave number can be too large resulting in abnormal vibration of the inner ring. The maximum fundamental frequency deviation between simulation and test is 2.75 Hz， the maximum error is 0.37%. This research can be used for the optimal design of the full ceramic bearing structures as well as for health monitoring.