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The carbon fiber with high strength, high modulus, fatigue resistance, excellent performance, carbon fiber reinforced composites has been widely used in many areas of aerospace, weapons manufacturing, automotive parts. As a representative of a new generation of high-performance fibers, T700 grade carbon fiber has a broad application prospects. China's own production of carbon fiber composite materials imports T700 carbon fiber and composite materials, in terms of performance, there is a great gap, which is mainly made of carbon fiber imported carbon fiber surface properties and interfacial characteristics on differences 's. Conducted a systematic analysis and research in order to provide a useful reference and guidance to the production of the domestic high-performance carbon fibers, this paper imports T700 carbon fiber surface properties and interfacial properties of the composites. To characterize imports T700 carbon fiber surface properties. Aspects of physical properties, the use of the surface interfacial tension of the surface of the fibers and wettability test, the T700 carbon fiber surface energy 49.15mJ · m-2, indicating that the surface is a non-polar inert surface, it with an epoxy resin a contact angle of 48.85 °; using an atomic force microscope (AFM) to characterize the roughness of the surface of the fibers, the T700 carbon fiber surface is relatively smooth, and no obvious grooves and defects; the fiber surface of the slurry layer has a thickness of approximately 35.5nm and sizing uniformity of the slurry is not ideal. Chemical properties, the use of X-ray photoelectron spectroscopy (XPS) test on the chemical composition of the surface of the fiber to obtain the T700 carbon fiber surfaces containing C, O, N, Si four elements, and its content were 72.79%, 25.78%, 0.48 % and 0.95%, the surface of the fiber mainly containing CC, CO, C = O three chemical groups, and its content were 44.83%, 47.02% and 8.15%; using thermal gravimetric analysis (TG) on the surface of the T700 carbon fiber slurry resistance heat analyzed to obtain a slurry, the initial decomposition temperature of 256.8 ° C. Similarly, to characterize the physical and chemical properties of the imports the T700 of carbon fiber composite material interface. Physical performance, T700 carbon fiber reinforced composite interface shear strength about 48.54MPa; modulus T700 carbon fiber and the matrix resin composites varied, the lack of an effective transition area. Chemical properties, under certain conditions, the T700 carbon fiber import surface can occur with the slurry effective chemical reaction between the two, having a better reactivity; After hygrothermal aging treatment, the interfacial shear strength of the composite material becomes 40.75MPa, strength decreased by about 15%, the T700 carbon fiber reinforced composite interface resistance to heat aging properties.
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