20140356534 | METHOD FOR THE CHEMICAL VAPOR INFILTRATION OF REFRACTIVE SUBSTANCES - Method for chemical vapor infiltration of refractory substances, wherein a porous structure is subjected in a reaction zone to the flow of a gas containing at least one gaseous precursor, wherein the partial pressure of the precursor and the dwell time of the gas are set at a given temperature in such a manner that a deposition reaction of the precursor occurs in the porous structure in the partial pressure range of the saturation adsorption and the reaction of the precursor is limited in each stage of the infiltration in such a manner that during the flow through the reaction zone no more than 50% of the precursor are deposited as a solid phase in the porous structure, and the exposure of the porous structure to the flow occurs in a stack of superimposed layers through ring-shaped vertical circumferential gaps (A, B) as well as through transverse gaps (C) which are open towards the circumferential gaps (A, B). The outer circumferential gap (A) is open both towards the inlet side and towards the outlet side of the reaction zone, while the inner circumferential gap (B) is closed towards the inlet side and towards the outlet side and has a gap width that is greater than the outer gap (A). | 12-04-2014 |