Pitch based carbon fibers pbcf

Cellulose based carbon fibers tend to be used for ablative applications, which require lower thermal conductivity and enhanced insulating properties than other carbon-carbon materials. The precursor for this product is rayon, which when carbonized, produces rayon based carbon fibers (RBCF). This type of fiber is usually more porous and weaker, which lowers its effective thermal conductivity. At high temperatures, it oxidizes and/or evaporates without disintegration, producing an evaporative cooling effect. 

There is now, to the knowledge of the author, only one supplier of the precursor and Polycarbon is the only one manufacturer of the RBCF. It is expensive to produce, with yields in the region of 30% and it is only existing government contracts which make production feasible. 

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