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Moving components materials in orbit environment require surface modification with stable lubrication for preventing increase in friction due to oxidation and irradiation damages. We have prepared a stainless steel substrate and four kinds of lubricative coatings such as TiN, MoS2, mixture of Cu and BN and Cu on the substrates and installed them on the International Space Station in orbit for exposure test from about a year to three years. We have analyzed tribological properties, surface roughness, chemical concentration and so on. Most of a year exposed substrates generally decrease friction in a vacuum as well as at an atmospheric pressure and over years exposure increased friction of almost substrates. XPS analysis shows Si based contamination layer that might affect the change in tribological properties., Meeting Information: International Symposium on "SM/MPAC & SEED Experiment" (International Congress Center EPOCHAL TSUKUBA, 10-11 March 2008)