Wear properties of carbon composite reinforced by vapor-grown carbon fibers treated with nitric acid and aqueous hydrogen peroxide

Carbon nanofiber-reinforced carbon composites (C/C composites) were prepared from furan resins filled with vapor-grown carbon fibers (VGCFs) that had previously been treated with nitric acid or aqueous hydrogen peroxide. Their wear properties were compared to those of C/C composites reinforced by untreated fibers. The relative wear volumes of C/C composites reinforced by HNO3-treated fibers were slightly lower and those of C/C composites by H2O2aq.-treated fibers were significantly lower than those of C/C composites by untreated fibers. The higher wear resistance is inferred to be due to improved anchoring of the fibers in the C/C composites because of roughening of the fiber surface after treatment with H2O2aq. A lubricous sliding surface, which is suggested to be controlled by the adhesive wear mechanism, was formed on the C/C composite prepared from H2O2aq.-treated fibers after the wear tests. The mechanism is implied to be responsible for the higher wear resistance.