Abstract: A method of fabricating a thermostructural composite material part includes making a fiber preform formed of yarns or tows and impregnated by a consolidating composition containing a carbon- or ceramic-precursor, transforming the carbon- or ceramic-precursor by pyrolysis, and then densifying the preform by chemical vapor infiltration. A consolidating composition is used that additionally contains refractory solid fillers in the powder form presenting mean grain size less than 200 nanometers and leaving, after pyrolysis, a consolidated solid phase in which the carbon or the ceramic derived from the precursor occupies a volume representing 3% to 10% of the apparent volume of the preform, and the solid fillers occupy a volume representing 0.5% to 5% of the apparent volume of the preform.

Abstract: A turbomachine blade or vane of composite material comprising fiber reinforcement densified by a matrix is fabricated by a method comprising: making a one-piece fiber blank by three-dimensional weaving; shaping the fiber blank to obtain a one-piece fiber preform having a first portion forming a blade airfoil and root preform and at least one second portion forming a blade platform preform; and densifying the preform with a matrix to obtain a composite material blade or vane having fiber reinforcement constituted by the preform and densified by the matrix, forming a single part with at least one incorporated platform.

Abstract: A turbine engine turbine blade of ceramic matrix composite. The root of the blade includes a single densified fiber preform including at least one recess made by machining, each point of the root of the blade being situated at a distance from a free surface of the root that is no greater than twice the maximum penetration distance into the preform of densification gas for densifying the preform, and the distal portion of the root of the blade includes a distal wall that is continuous and in a single piece.

Abstract: A method of smoothing the surface of a ceramic matrix composite material part that presents a surface that is undulating and rough. The method includes depositing a refractory vitreous coating on the surface of the part, the vitreous coating essentially containing silica, alumina, baryte, and lime.

Abstract: A method of fabricating a turbomachine blade out of a composite material including fiber reinforcement densified by a matrix, the method including making a one-piece fiber blank by three-dimensional weaving; shaping the fiber blank to obtain a one-piece fiber preform having a first portion forming a blade airfoil and root preform and at least one second portion forming a preform for an inner or outer blade platform; and densifying the preform with a matrix to obtain a composite material blade having fiber reinforcement constituted by the preform and densified by the matrix, fowling a single part with incorporated inner and/or outer platform.

Abstract: A method of fabricating a complex part out of composite material including three-dimensional woven fiber reinforcement densified by a matrix, the method including three-dimensionally weaving a continuous fiber strip including a succession of fiber blanks for preforms of a plurality of parts that are to be fabricated; subsequently cutting individual fiber blanks out from the strip, each blank being a one-piece blank; shaping a cut-out blank to obtain a one-piece fiber preform having a shape that is close to the shape of a part that is to be fabricated; consolidating the preform in the desired shape; and densifying the consolidated preform by forming a matrix by chemical vapor infiltration.

Abstract: A method of smoothing the surface of a ceramic matrix composite part presenting a surface that is undulating and rough. The method includes forming a ceramic coating on the surface of the part, the coating being made by applying a liquid composition on the surface of the part, the composition containing a ceramic-precursor polymer and a factory solid filler, curing the polymer, and transforming the cured polymer into ceramic by heat treatment. The method further includes impregnating the ceramic coating with a liquid metallic composition.

Abstract: A method of fabricating a thermostructural composite material part includes making a fiber preform formed of yarns or tows and impregnated by a consolidating composition containing a carbon- or ceramic-precursor, transforming the carbon- or ceramic-precursor by pyrolysis, and then densifying the preform by chemical vapor infiltration. A consolidating composition is used that additionally contains refractory solid fillers in the powder form presenting mean grain size less than 200 nanometers and leaving, after pyrolysis, a consolidated solid phase in which the carbon or the ceramic derived from the precursor occupies a volume representing 3% to 10% of the apparent volume of the preform, and the solid fillers occupy a volume representing 0.5% to 5% of the apparent volume of the preform.

Abstract: The method comprises the steps of: forming a porous fiber-reinforcing structure; introducing into the pores of the fiber structure powders containing elements for constituting the composite material matrix; and forming at least a main fraction of the matrix from said powders by causing a reaction to take place between said powders or between at least a portion of said powders and at least one delivered additional element; the powders introduced into the fiber structure and the delivered additional element(s) comprising elements that form at least one healing discontinuous matrix phase including a boron compound and at least one discontinuous matrix phase including a crack-deflecting compound of lamellar structure. At least a main fraction of the matrix is formed by chemical reaction between the powders introduced into the fiber structure and at least one delivered additional element, or by sintering the powders.

Abstract: A refractory porous fiber substrate is densified by forming a solid matrix deposit from a fluid composition containing a reagent fluid that is a precursor for the material of the solid deposit that is to be formed, together with an optional dilution fluid. The operation is performed at a temperature and a pressure that enable the reagent fluid and/or the optionally-present dilution fluid to be maintained in the supercritical state, while spontaneously and directly forming the solid deposit of the matrix, thereby enabling the duration of the process to be reduced considerably compared with conventional CVI methods.