A study on the lapping of ceramic balls

Ceramic balls are used extensively in hybrid precision bearings which show advantages in high speed, high temperature, high load and hostile environment. Surface quality generated from the final finishing processes of those balls is critical to the rolling contact fatigue performance. A brief review on the finishing process of ceramic balls is presented. The design of an experimental eccentric lapping apparatus which allows lapping of 13.4 mm diameter ceramic bail blanks at a small batch (15 balls each time) is described. Preliminary experimental investigation on the influences of the lapping load and speed, the diamond particle sizes, the different lapping fluid mixtures has been conducted. Finished ball surfaces are examined by optical microscopy and Scanning Electron Microscopy, and surface quality in relation to different lapping processes is discussed. The optimum lapping parameters from this study is proposed and further research aspects are pointed out.