Carbon composite materials

Shear-stress-shear-strain curves typical of fiber-reinforced epoxy resins are quite nonlinear, but all other stress-strain curves are essentially linear. Hahn and Tsai [6-48] analyzed lamina behavior with this nonlinear deformation behavior. Hahn [6-49] extended the analysis to laminate behavior. Inelastic effects in micromechanics analyses were examined by Adams [6-50]. Jones and Morgan [6-51] developed an approach to treat nonlinearities in all stress-strain curves for a lamina of a metal-matrix or carbon-carbon composite material. Morgan and Jones extended the lamina analysis to laminate deformation analysis [6-52] and then to buckling of laminated plates [6-53]. 

CNF is an industrially produced derivative of carbon formed by the decomposition and graphitization of rich organic carbon polymers (Fig. 14.3). The most common precursor is polyacrylonitrile (PAN), as it yields high tensile and compressive strength fibers that have high resistance to corrosion, creep and fatigue. For these reasons, the fibers are widely used in the automotive and aerospace industries [1], Carbon fiber is an important ingredient of carbon composite materials, which are used in fuel cell construction, particularly in gas-diffusion layers where the fibers are woven to form a type of carbon cloth. 

Materials engineers arc becoming very interested in buckytubes because they may perform better than graphite in carbon-carbon composite materials, as currently used in aircraft. 

Sun, X., Yan, J., Yang, X., Wang, E., Electrochemical detector based on sol-gel-derived carbon composite material for capillary electrophoresis microchips. Electrophoresis 2004, 25, 3455-3460. 

Gordeev S.K. Nanoporous and nanofragmental carbon composite materials. In G. Benedek et al. (eds.) Nanostructured carbon for advanced applications, Kluwer Academic Publishers, 2001, pp. 71-88. 

Carbon fibers and carbon-carbon composite materials... 

Carbon/carbon composites fabricated by multiple cycles of liquid impregnation and recarbonization are a typical example of modern petroleum derived carbons. In the 1975 ACS Symposium on Petroleum Derived Carbons (JL), papers were presented on carbon/carbon composite materials formed by pyrolytic infiltration processes (2 ) or by liquid impregnation with petroleum pitch (3,4), on fabrication processes for high-modulus carbon fibers based on polyacrylonitrile (PAN) or pitch precursors ( 5 ), and on the use of carbon materials for thermostructural (6 ) as well as biomedical applications (1 ) ... 

Zhao, R, Wu, X., Wang, M., Liu, Y, Gao, L., and Dong, S. 2004. Electrochemical and bioelectrochemistry properties of room-temperature ionic liquids and carbon composite materials. AnaZyh caZ Chemistry, 76 4960-7. 

Joerger, R., Klaus, T., and Granqvist, C.G. 2000. Biologically produced silver-carbon composite materials for optically functional thin film coatings. Advanced Materials, 12 407-9. 

Primary applications of carbon-carbon composite materials are in the aerospace industry, where in spite of their high cost, they can still be very cost effective. The use of carbon-carbon composites for the brakes of the Concorde supersonic aircraft is reported to have produced a weight saving of over 10001b, which translates into significant economies in operation. 

Rovillain D, Trinquecoste M, Bruneton E, Derre A, David P, Delhaes P (2001) Film boiling chemical vapor infiltration an experimental study on carbon/carbon composites materials. Carbon 39 1355-1365... 

Preliminary results show it should be possible to operate the MHR with a coolant outlet temperature of up to 1 000°C using nuclear-grade graphite fuel blocks, carbon-carbon composite materials for control rods and other internal reactor components, and existing coated-particle fuel technology with silicon carbide (SiC) and pyrolytic carbon coatings. 

S.E. Bukharov, Up-to-date aspects of the development of polymer and carbon composite materials. Moscow (2002) (in Russian). 

Next to mechanical properties, the most important characteristics of a carbon-carbon composite(C/C) are thermal conduction and thermal expansion. In this paper, several investigations have been made into carbon fiber arrangement relationships for different carbon-carbon composite materials. Pitch-derived carbon matrix-carbon fiber composites have been used, processed by means of the hot isostatic pressing (HIP) technique for converting pitch into a dry carbon fiber preform. Repeated HIP cycles are required to build the composite matrix up to an acceptably high density/low porosity for deployment in severely ablative environments. 

The concept of supercritical fluid infiltration (SFI) was first described in 1981. Subsequently under DOD funding (a joint program from Air Force Office of Scientific Research/Defense Advanced Research Projects Agency, AFOSR/DARPA) SFI was addressed to the problem of improving the oxidation resistance of carbon/carbon composite materials used in rocket engines and missile nose cones (Wagner, Krukonis, and Coffey, 1988). 

Developed carbon composite material with graphite particulate filler to control pore size and speed surface sealing. 

Develop carbon/carbon composite materials for bipolar plates that meet or exceed target property criteria... 

Thermoplastic carbon composite materials are a favonrable material combination for bipolar plates becanse they can be mannfactnred by the mass production process of injection monlding [102]. Electrical condnctivity of a carbon composite requires a high content of carbon, nsnally a mixtnre of graphite and active coal. The percolation limit of the graphite in the polymer binder has to be exceeded, leading to direct contact between graphite particles. Additionally, a basic condnctivity of the polymer matrix by the smaller active carbon particles is achieved. The injection... 

Carbon composite materials are used widely in a number of applications, including high-performance graphite sports equipment such as tennis racquets, golf clubs, and bicycle wheels (T FIGURE 22.31). Heat-resistant composites are required for many aerospace applications, where carbon composites now find wide use. 

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