Air-oxidation and anodization of pitch-based carbon fibers

Pitch-based high modulus carbon fibers were oxidized in air and characterized using the coulostatic method in order to compare them with anodized fibers. The interfacial shear strength (IFSS) of these fibers to an epoxy resin was evaluated by a micro debonding test. The results showed a good correlation between the differential double layer capacities, Cd, which were measured by the coulostatic method, and the IFSS values for air-oxidized and anodized fibers. In order to investigate the variation of the air-oxidation and anodization in the tow, the coefficients of variation for the Cd and polarization resistance (Rp) by the mono-filament coulostatic method were compared. As a result, the variation of oxidation in the tow of air-oxidized fiber seemed to be slightly larger than that of anodized fiber.