Analytical study about effects of lubrication on dynamic characteristics of defect-ball ceramic bearing

Due to the self-lubrication and high stiffness, the ceramic bearings are widely applied in mechanical system. However, under some complex working conditions, the happening of defection and uncertain lubrication on the ball's surface is complex. Insufficient oil may increase friction and shorten defect bearing's life. In the paper, the self-lubrication characteristic of defect-ball ceramic bearing is considered to investigate the lubrication performance. Firstly, a novel lubrication model of ceramic bearing is established through Hamrock-Dowson theory. Then, the Newton–Raphson method is employed to analyze the dynamic of defect bearing. Finally, the effect of oil film thickness on the dynamic characteristic of ball-defect ceramic bearing is explored systematically. A vibrometer and the temperature sensors are used in the experiment to validated the accuracy of model. The vibration of defect-ball bearing is highly accord with the experiment, with an error less than 5%. The results indicate that enlarging the volume fraction of oil appropriately improve the effect of lubrication on dynamic of defect bearing. It will decrease the vibration of defect-ball bearing in high-speed condition. Research results have a significance guidance about the oil supply amount on the defect-ball ceramic bearing under a certain condition.