Lubricants for High-Vacuum Applications

This report reviews the selection criteria and performance of lubricants in vacuum environments found in terrestrial equipment and in and around space vehicles. Vacuum, mechanical, and thermal conditions of such lubricant use are outlined. Tribology issues are defined that should be considered in initial design of systems used in terrestrial equipment or space vehicles. The types of vacuum lubricants that are available dry or solid, liquid, or grease are reviewed, their properties and applicability to general situations are assessed, and the option of not lubricating is discussed. Examples of specific applications and performance data for lubricants in space and on earth are presented.