펄스화학기상침투법에 의한 탄소/탄소 복합재료의 치밀화에 있어서 가스유지시간 유무의 영향

Abstract

Two-dimensional carbon/carbon preforms made of PAN-based carbon yarn and phenolic resin were densified with pyrolysis of propane by pulse chemical vapor infiltration, where repeated the cycle of gas introduction, residence and evacuation. Maximum density increment was 14% when infiltration temperature and time were 1000℃ and 21.25 hrs, respectively. The distribution of deposits of pyrocarbon by this process has been occurred uniformly in the bottom, middle and top of carbon/carbon composite preform. Pulse CVI with residence is most effective in increasing density and shortening infiltration time among isothermal CVI and pulse CVI with and without residence.