Chemical vapor deposition method

摘要

Method for densifying a porous carbon preform ( 5 ). The method includes the steps of: (a) providing the apparatus ( 11 ); (b) charging the apparatus ( 11 ) with a plurality of stacks of annular porous carbon preforms ( 5 ), the preforms being separated from one another by spacers ( 15 ); (c) locating the charged apparatus ( 11 ) in a furnace at a temperature in the range of 950-1100° C. and a pressure in the range of 5-40 torr; and (d) circulating a natural gas reactant blended with up to 15% propane through the apparatus for a period of from 150 to 900 hours. Carbon-carbon composite preforms made by this method may be configured as aircraft landing system brake discs or racing car brake discs.