炭素繊維への熱分解黒鉛の被覆 Carbon Fiber Coated with Pyrolytic Graphite

In order to improve not expensive, “regular grade” carbon fiber, a yarn of the carbon fiber prepared from lignin/poval was coated with pyrolytic graphite. Coating was carried out with methane of 10 Torr. in the temperature range of 1200°-1900°C at the gas flow rates of 35-420m<i>l</i>/min. (stp).<br>The properties of the carbon yarn coated with pyrolytic graphite depended upon the conditions in which it was deposited. Coated yarns with layer of pyrolytic graphites thicker than ca. 2μ were not so flexible.<br>The yarn was derived which was so strong as 59.08kg/mm²; or which lost only less than 10wt% in 5 minutes in the air of 900°C; or which had specific electric resistance of 3.569×10^-4Ωcm.