Tests of 38 Ball-Bearing Greases

Report presents interim results in program of long-term tests of ball-bearing greases in vacuum, oxidizing, and otherwise hostile environment. Program is motivated by need for mechanisms that will operate for long periods in spacecraft or space stations. Class of lubricants based on perfluoroalkylpolyether (PFPE) with fluorotelomer thickeners has given best results in vacuum tests completed thus far. Test methods and performances of various lubricants could be of interest in automotive and industrial communities.