Japan Aerospace Exploration Agency Institute of Space Technology and Aeronautics
Japan Aerospace Exploration Agency Institute of Space Technology and Aeronautics
Japan Aerospace Exploration Agency Institute of Space Technology and Aeronautics
Lifetime tests of ball bearings fitted with retainers impregnated with four different oils, three perfluoropolyethers and one synthetic hydrocarbon, were conducted in a vacuum. Outgassing experiments were also carried out with similar impregnated retainers and with a small quantity of oil contained in a stainless steel container, as a function of the temperature. The bearings lubricated with the synthetic hydrocarbon oil showed excellent performance, lifetime of over 10,000 hours and low outgassing characteristics. For the bearings lubricated with perfluoropolyethers, degradation of the oils and frictional torque of the bearings were correlated from analysis of the torque and outgassing data. Outgassing experiments confirmed that the outgassed species formed a signature for perfluoropolyethers when they degraded.