Tribology for space applications

Abstract

Historically, space mechanism lubricant choices were based on space heritage rather than on the latest technology or best available materials. With the limited mission lives and minimal duty cycles of the early space programme, this strategy was highly successful. As missions extended, other spacecraft components, such as electronics, batteries, and computers, failed before lubricated mechanisms; however, during the 1980s and 1990s, these ancillary components vastly improved and tribological systems became a main factor limiting spacecraft reliability and performance. Although tribological components represent only a small fraction of the spacecraft's cost, they are often single-point failures that cripple or debilitate expensive spacecraft. This paper will discuss the following: common space lubricants, mechanism components, testing, and factors affecting lubricant selections.