Carbon materials graphitization process

The raw materials used ia the production of manufactured carbon and graphite largely control the ultimate properties and practical appHcations of the final product. This dependence is related to the chemical and physical nature of the carbonization and graphitization processes. 

Carbon Composites. In this class of materials, carbon or graphite fibers are embedded in a carbon or graphite matrix. The matrix can be formed by two methods chemical vapor deposition (CVD) and coking. In the case of chemical vapor deposition (see Film deposition techniques) a hydrocarbon gas is introduced into a reaction chamber in which carbon formed from the decomposition of the gas condenses on the surface of carbon fibers. An alternative method is to mold a carbon fiber—resin mixture into shape and coke the resin precursor at high temperatures and then foUow with CVD. In both methods the process has to be repeated until a desired density is obtained. 

Kelly, B.T., Physics of Graphite, Applied Science Publishers, London, 1981. Burchell, T.D., Radiation damage in carbon materials. In Physical Processes of the Interaction of Fusion Plasmas with Solids, ed. J. Roth and W.O. Hoffer, Academic Press, San Diego, 1996, pp. 341 384. 

The product of this process can be modified in many ways. It can be made impervious by impregnation or its pores may be filled with metal such as in motor and generator brushes. It must be appreciated that by choice of raw materials and processing it is possible to produce a wide range of carbons, c bon/graphites and electro-graphites. The physical properties shown in Table 18,1 are thus to be taken only as broadly representative. 

Among the carbon materials, different types of graphite have long been nsed in a number of technical electrochemical processes (e.g., as anodes in electrochemical... 

Combined with appropriate amorphous carbon precursors graphite intercalation compounds could be used in one-stage process of production of carbon-carbon composites, which could possess attractive properties for such applications as supercapacitors elements, sorbents as well as catalyst supports and materials for energy- and gas-storage systems. 

Asbestos fibers are found worldwide in many products as reinforcement in cement water pipes and the inert and durable mesh material used in filtration processes of chemicals and petroleum, for example. However, asbestos is not the only inorganic fiber in use today. Synthetic inorganic fibers abound. Glass fibers have replaced copper wire in some intercontinental telephone cables. Fiberglas (a trade name) has become the insulation material of choice in construction. Carbon and graphite fiber composites are favored materials for tennis racket frames and golf clubs. Fibrous inorganic materials have become commonplace in our everyday lives. 

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