High thermal conductivity carbon fibers

Edie, D. D., Robinson, K. E., Fleurot, O., Jones, S. P. and Fain, C. C., High thermal conductivity ribbon fibers from naphthalene-based mesophase. Carbon, 1994, 32(6), 1045 1054. 

Duffy, D.R., Ting, J.-M., Guth, J.R. and Lake, M.L., Carbon fiber reinforced lightweight composites with ultra high thermal conductivities, Proc. Int. JEPC, Atlanta, GA, Sept., 1994, pp. 442 448. 

Ting, J.M. and Lake, M.L., Vapor grown carbon fiber reinforced aluminum composites with very high thermal conductivity J. Mat. Res., 1995, 10(2), 247 250. 

Certain types of carbon fibers can have extremely high thermal conductivity. Examples of such carbon fibers include ... 

Pitch-based high thermal conductivity carbon fiber... 

Amoco has developed a family of ultra high modulus continuous graphite fibers and preforms with axial thermal conductivity to llOOW/mK. The extremely high thermal conductivity is a direct result of an extremely high degree of crystallinity during carbonization of the mesophase pitch precursor fiber. Table... 

Different grades of chopped low-carbon steel fibers are used as reinforcements and friction enhancers in formulations. Steel fibers have good reinforcing properties and thermal resistance but high density, poor corrosion resistance, and high thermal conductivity. Chopped stainless steel fibers have found limited application in friction materials and backing layers. Some manufacturers have developed annealed and softer grades of steel fiber to reduce rotor and drum wear. 

Carbon fibers, which utilize the preferred orientation of the graphene layers, show not only high modulus and high strength but also high thermal conduction and low thermal expansion along the fiber axis. On the basis of these properties, fiber reinforced materials present the opportunity to design the thermal properties into materials. 

The forced flow-thermal gradient CVI process (FCVI) has been shown to permit the rapid consolidation of SiC matrix composites. Recently, the FCVI process has been extended to the fabrication of carbon fiber-carbon matrix composites. Using 2D carbon cloth preforms, composite disks 0.8 cm thick have been fabricated in less than three hours a small fraction of the time required for either the resin/pitch or conventional CVI processing. Further, the FCVI process facilitates the incorporation of oxidation inhibitors within the carbon matrix and may permit obtaining a preferred crystallographic orientation that yields the high thermal conductivity required for thermal management applications. 

Ordinary carbon fibers exhibit high thermal conductivity. If carbon fiber composites are used for thermal insulation, they must be modified. This could be done by disturbing the lattice with a fluorine treatment. 

Because most development work has been done on non-oxide materials, particularly SiC fiber-reinforced SiC CMCs (SiC/SiC) with fiber interfacial coatings of either carbon or boron nitride, non-oxide CMCs are more advanced than oxide CMCs. Non-oxide CMCs have attractive high temperature properties, sueh as creep resistance and microstructural stability. They also have high thermal conductivity and low thermal expansion, leading to good thermal stress resistance. Therefore, non-oxide CMCs are attractive for thermally loaded components, such as combustor liners (see Figure 1-4), vanes, blades, and heat exchangers. 

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