ELECTROCHEMICAL PROPERTIES OF NICL2-INTERCALATED AND REDUCED-NICL2-INTERCALATED GRAPHITE

The feasibility of modifying graphite, by intercalation, to reduce gal vanic reactions in carbon fiber reinforced metal matrix composites is investigated. A nickel chloride intercalation ComPound (NiCl2-GIC) and a reduced nickel chloride intercalation compound were prepared (r-NiC l2-GIC), and their electrochemical properties studied in deaerated 0.1 N NaCl. The open-circuit potential of NiCl2-GIC is about 0.500 V more positive than that of natural graphite while that of r-NiCl2-GIC is a bout 700 V more negative than that of natural graphite. In the latter case, the potential difference relative to aluminum is reduced by abou t 50%. Distinct changes in the cathodic behavior of graphite upon inte rcalation and reduction are also observed. Results are discussed in te rms of the effects of these changes on galvanic interactions with alum inum alloy Al 6061-T6.