In order to reveal the thermal characteristic evolution of silicon nitride full ceramic ball bearings over their entire service life and improve their service life, a full life test of silicon nitride full ceramic ball bearings was conducted under dry running conditions. The temperature rise data from the full life test were analyzed and processed. Subsequently, a thermal model for the bearing was established for simulations under dry running conditions. Through the full life test research and data analysis, it was found that during the running-in phase, the bearing temperature rises rapidly. After the running-in phase, the bearing temperature stabilizes and fluctuates minimally over a longer period. The thermal performance of the bearing is stable, with a temperature rise of approximately 27.6 °C. When the bearing cracks but has not yet experienced spalling, the temperature increases slightly compared to other bearings. When spalling occurs, the temperature rises rapidly and significantly. The model established was verified experimentally, with the error not exceeding 9%. The experimental results provide significant data and theoretical basis for the full life and thermal performance of silicon nitride full ceramic ball bearings under dry running conditions. Additionally, the reliability of the thermal model was validated through the full life test. This research holds significant value in improving and predicting the full life and service performance of silicon nitride full ceramic ball bearings in dry running conditions.

Keywords: Silicon nitride, Full ceramic ball bearings, Full life, Temperature rise characteristics, Service performance.