Theory and practice of self-lubricated, oscillatory bearings for high-vacuum applications. I - Selection of the self-lubricating composite retainer material

A seven-year, interdisciplinary effort was recently completed successfully in developing self-lubricated bearings capable of continuous oscillatory motion for the equivalent of 5+ years in high vacuum, while maintaining arc-second-alignment accuracy of precision gimbal-pointing mechanisms. This paper describes the selection method for the PTFE-based, polymeric self-lubricating composite, which was eventually used as the lubricative retainer. The method consisted of statistical matrices of oscillatory sliding- and rolling-element friction and wear tests completed with commercially available and special test apparatus.