Influence of the Typical Low-orbital Irradiation Environment on the Tribological Performance of MoS₂-Ti Film in Vacuum

The specimens of MoS₂-Ti film on substrate of 9Cr18 were prepared by the method of unbalanced magnetron sputtering, and then different kinds of irradiation experiments were conducted for five group specimens, which of them were no irradiation, electron, electron/proton, electron/proton/ultraviolet, electron/proton/ultraviolet/atomic oxygen.Through the characterizations of SEM, XRD, XPS profile analysis and friction tests, the influence of each irradiation on the film's microstructure, chemical components and tribological performance in vacuum was studied comprehensively. The results revealed there were not great effects on the microstructure, surface morphology and tribological performance, caused by the irradiation of electron, proton, ultraviolet. The atomic oxygen with an energy of 5 eV showed strong damage effects on the film, leading to the ‘blanket-like’ surface morphology, the oxidation of Mo, S, Ti, which resulted in the increase of friction coefficient at initial and middle stages, fluctuation at middle states, as well as the increase of specific wear rate.