“…The common dry lubricating materials mainly contain polymer, graphite, copper alloy, MoS 2 composites, soft metal coatings (Pb, Au, Ag, In), diamond-like carbon, etc. [3][4][5][6] As we all know that dry lubricants were not used for space equipment due to the harsh operating conditions such as high vacuum, the requirement of long lifetime, high contact pressure, high sliding speeds, repeated start/stop, and low torque noises. The liquid lubricants were largely concentrated on multialkylated cyclopentanes, perfluoropolyethers (PFPE), ionic liquids, and silicone oils and have been used in aerospace industry.…”