Chemical gas phase infiltration process for densification of porous substrates by pyrolytic carbon

摘要

Chemical gas phase infiltration process for densification of porous substrates by pyrolytic carbon.One or more porous substrates to be densificados (10) are loaded into a furnace (12) at the entrance of which is admitted to a gaseous phase containing a reactive gas precursor of pyrolytic carbon comprising at least a gaseous hydrocarbon (C ~ x ~ H ~ y ~ in which X and y are integers and X Is such that 1 x 6, and a gas carreador selected from methane and neutral gases.The gas effluent containing constituents of the gaseous phase admitted, and the residual reaction products, such as hydrogen, are extracted from the furnace and recycled circuit (80) in the gas phase reactive admitted at the entrance of the oven, a fraction of at least a gas flow from the gas effluent and C Reactant gas containing precursor of pyrolytic carbon.The recycling being carried out after removal of heavy hydrocarbons (40) contained in the effluent gas.