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Pyrolytic carbon is a material similar to graphite, but with some covalent bonding between its graphene sheets as a result of imperfections in its production. Pyrolytic carbon is man-made and not found in nature.〔Ratner, Buddy D. (2004). Pyrolytic carbon. In ''(Biomaterials science: an introduction to materials in medicine )''. Academic Press. p. 171-180. ISBN 0-12-582463-7. Google Book Search. Retrieved 7 July 2011.〕 Generally it is produced by heating a hydrocarbon nearly to its decomposition temperature, and permitting the graphite to crystallise (pyrolysis). One method is to heat synthetic fibers in a vacuum. Another method is to place seeds or a plate in the very hot gas to collect the graphite coating. ==Physical properties== Pyrolytic carbon samples usually have a single cleavage plane, similar to mica, because the graphene sheets crystallize in a planar order, as opposed to graphite, which forms microscopic randomly oriented zones. Because of this, pyrolytic carbon exhibits several unusual anisotropic properties. It is more thermally conductive along the cleavage plane than graphite, making it one of the best planar thermal conductors available. Pyrolitic graphite forms mosaic crystals with controlled mosaicities up to a few degrees. It is also more diamagnetic (χ = −4×10−4) against the cleavage plane, exhibiting the greatest diamagnetism (by weight) of any room-temperature diamagnet. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Pyrolytic carbon」の詳細全文を読む スポンサード リンク
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