CHEMICAL VAPOR INFILTRATION OF 3D FIBROUS CARBON PREFORMS BY ZIRCONIUM CARBIDE

Abstract
The purpose of this paper is to study the infiltration efficiency of the process in the case of ZrC obtained from a ZrCl₄-CH₄-H₂ initial gas mixture. 3D carbon preforms are infiltrated for 8 hours in a hot wall reactor. An experimental design is used to determine the influence of the main factors such as temperature, total pressure and the hydrogen flow rate. The mass increase, as well as the distribution profile of the ZrC infiltration on a cross section of the sample, are measured for each of the eight conditions of a complete factorial design 2³. After quantification of the penetration depth of the ZrC coating into the preform both responses are fitted by a polynomial expression. The resulting response surfaces are presented and discussed.