Preparation of carbon/carbon composites by microwave pyrolysis chemical vapour infiltration

Microwave pyrolysis chemical vapour infiltration was used for the rapid fabrication of carbon/carbon composites. The carbon fibre felts (the bulk density≈0·2 g cm−3) were densified with the total pressures of 50 kPa and CH4/N2 = 1 : 4 at 1100 and 1150°C respectively. The results show that the carbon/carbon composites with the bulk density 1·70 g cm−3 can be fabricated at 1100°C for 90 h, and the composites are densified from the inside out. The stereomicroscope images reveal that the surfaces of composites are not sealed at 1100°C, and the pyrolytic carbons are deposited uniformly on the fibres. The polarised light images show that the pyrocarbon textures are the rough laminar carbons.