Comparative assessment of the performance of hard-lubricating coatings for operation in vacuum conditions

As a result of the analysis of tribo-tests according to the "ball-disc" scheme of solid-lubricant coatings (SLC) of magnetron deposition on the TriboLAB device installed in the EuTEF ESA multifunctional equipment of the Columbus module of the International Space Station, the average resource of 11915 minutes was calculated. friction couplings with a MoSx — WC SLC, which exceeds a similar parameter in ground tests by 61.4%.The coefficient of friction of the specified MoSx — WC SLC composition 0.03 at the same time turns out to be 44.4 % higher than in ground tests. The analysis of the results of tribo–tests carried out on the TriboLab vacuum model under ground conditions showed that the average life of friction pairs with a MoSx — WC SLC composition is 3068 min. It is 38 % higher than that of MoS₂-based SLC without impurities. At the same time, the average coefficient of friction of the combined type 0.054 is 48 % higher than that of pure SLC. A comparative assessment of the resource of friction pairs in a _MoS2-based SLC under vacuum conditions obtained by various application methods showed that the greatest resource was found by a MoS2-based SLC with a thickness of 0.2 microns of the high-frequency spraying method 10000 min. at a contact friction temperature of 34.6 °С and a coefficient of friction 0.04.
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