Polishing of 3/4 Inch Silicon Nitride Balls Using the Large Batch Magnetic Float Polishing Apparatus

Abstract

The purpose of this study was to polish 3/4 inch silicon nitride (Si3N4) balls to the best possible sphericity and surface finish using the large batch magnetic float polishing apparatus. Objectives included: 1) optimize the system design so that consistent and repeatable results could be obtained, 2) investigate the parameters involved in order to develop a sequence of polishing runs that will produce a batch of ball to the best sphericity and surface finish. Parameters in this study are abrasive, load, speed, and run duration. Two batches of balls have been polished. Modifications were made to the design which enabled the results to be consistent for a given set of parameters. Following this, parameters were investigated and a polishing process was outlined which would polish a batch of forty-six balls in approximately twenty hours, to a quality level of grade 16, according to AFBMA specifications.