One of the major hurdles pertaining to anti-wear application of plasma sprayed alumina coatings is the high wear coefficient exhibited at their surfaces. The performance can be improved by addition of other materials, among which carbon fiber is an attractive candidate due to its super lubricity. In this study, carbon fibers with ～10μm in length and ～6μm in diameter were prepared by ball-milling approach. The coatings containing 1wt.%, 2wt.%, and 4wt.% carbon fibers were deposited using mechanically blended alumina/carbon-fiber powders. Results showed that carbon fibers are evenly distributed in the coatings and they adhere to the surface of alumina splats. Ball-on-disk wear test revealed significantly reduced wear coefficient by ～50% of the coatings containing 4wt.% carbon fiber compared to pure alumina coating (0.597vs.0.297). The lubricating effect offered by the porous carbon fibers was further elucidated, giving clear insight into possible less load-bearing applications of the self-lubricating composite coatings.
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