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The surface characteristics of various carbon and graphite fibers and the Interfaclal region between fibers and resin In composites were Investlgaced by using electron microscopy, electron diffraction and Raman spectroscopy. The latter technique permits differentiation between graphite fibers of different origin. Graphite fiber composites were prepared by in situ polymerization on nylon 6. This technique improves the wetting of the fibers and yields void-free compo&ites. Oriented crystallization of the monomers of nylon 6 and nylon 66 on graphite fibers and subsequent solid state reaction yielded dimers and trimers, respectively, instead of the usual polymers, thus showing a strong and specific effect of surface interactionsSophisticated vacuum microbalance equipment has been constructed to study t-.he surface characteristics of graphite fibers by gas adsorption. Work on graphite-fiber, nickel-matrix composites was concerned with improvements in the electrodepositlon process, the fabrication of larger test specimens, the fabrication of thin tape which can be further processed into samples of more complicated configurations, and the evaluation of composite properties. The latter included measurements of the elastic properties, stress-strain curves and composite thermal expansion. This abstract is subject to special export controls and each transmittal to foreign governments or foreign nationals nay be made only with prior approval of the Nonmetalllc Materials Division, MAN, Axr Force Materiaid Laboratory, Wright-Patterson Air Force Base, Ohio 45^33.