Published online by Cambridge University Press: 21 February 2011
Carbon fibers derived from various sources are surface modified by oxygen and nitrogen ion beams generated from a low voltage ion source. The surface analyses by X-ray photoelectron spectroscopy reveal that the ion treatment produces large abundances of various surface functional groups which are dependent on impinging ion energies and irradiation times. In the oxygen beam, the hydroxyl moiety is a dominant surface functionality, but in the nitrogen beam, various moieties containing oxygen and nitrogen are observed. The transverse tensile stresses of the epoxy composites made from the ion treated fibers are found to increase two to four times. The ion beam process yields the highest adhesive strength among all surface treatment methods.