Abstract：MoS2/Cu composite coating was deposited by air plasma spraying on 2A12 aluminum alloy substrate using MoS2/Cu composite powder as raw material. Microstructure and wear surface of coating were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and Raman spectra. The tribological properties of as-sprayed coating in vacuum were explored using GTM-3E ball-on-disc vacuum friction and wear instrument. The results showed that MoS2 particles were homogeneously distributed in the as-sprayed coating. The as-sprayed coating was dense and had good bonding with aluminum matrix. XRD analysis demonstrated that Cu, MoS2 and Cu2O phase were observed. Under the test conditions, the as-sprayed coating exhibited excellent friction reducing effect through the addition of MoS2 component, the obtained friction coefficients were in the range from 0.05 to 0.15. The low friction coefficient could be attributed to the formation of uniform MoS2 lubricating transfer film. The main wear mechanisms observed in vacuum were fatigue wear and brittle fracture.
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