Abstract: The invention relates to a method of fabricating a composite material part comprising fiber reinforcement densified by a matrix, the method comprising the steps of: making a fiber preform consolidated by impregnating (S4) a fiber texture made up of yarns with a liquid consolidation composition containing a precursor for a consolidating material, and by transforming (S7) the precursor into consolidating material by pyrolysis so as to obtain a consolidated preform that is held in shape; and densifying (S8) the consolidated fiber preform by chemical vapor infiltration; the method being characterized in that it includes, prior to impregnation (S4) of the fiber texture with the consolidation liquid composition, a step of filling (S2) the pores of the yarns of said fiber texture by means of a filler composition.

Abstract: A loader device for loading porous substrates of three-dimensional shapes extending mainly in a longitudinal direction into a reaction chamber of an infiltration oven for densification of the preforms by directed flow chemical vapor infiltration. The device comprising at least one annular loader stage formed by first and second annular vertical walls arranged coaxially relative to each other and defining between them an annular loader space for the porous substrates to be densified. First and second plates respectively cover the bottom portion and the top portion of the annular loader space. The first and second annular vertical walls include support elements arranged in the annular loader space so as to define between them unit loader cells, each for receiving a respective substrate to be densified. The device also comprises gas feed orifices and gas exhaust orifices in the vicinity of each unit loader cell.

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: Multilayer weaving is used to form a fiber blank having a longitudinal direction corresponding to the longitudinal direction of the vane to be made and comprising across its thickness a first woven portion with a plurality of layers of yarns interlinked by weaving, and also a second and third woven portions. The first portion is situated between the second and third portions and interlinked thereto by weaving over only a fraction of its longitudinal dimension. A preform for the vane is formed by folding out, on either side of the first portion, segments of the second and third portions not interlinked with the first portion, by shaping the first portion to form a preform portion for the airfoil of the vane, and by shaping the folded-out segments of the second and third portions to form preform portions for the inner and outer platforms of the vane to be fabricated.

Abstract: The invention relates to a turbomachine blade made of composite material and presenting a root with a bulb-shaped end suitable for engaging in a slot of a rotor disk. In characteristic manner, the end of the root of the blade is provided, beside one of its front faces, with a projecting portion having two symmetrical fins about the axial midplane of the root, each fin having a bearing face suitable for limiting tilting of the blade relative to the rotor disk about the axial direction.

Abstract: In order to protect a substrate having at least a portion adjacent to a surface that is made of a refractory material containing silicon, while the substrate is in use at high temperature in a medium that is oxidizing and wet, there is formed on the surface of the substrate an environmental barrier that contains no boron and that has at least one layer that is essentially constituted by a system of oxides formed by at least one rare earth oxide, silica, and alumina, and that is capable of self-healing by maintaining the presence of at least one solid phase in a temperature range extending up to at least 1400° C. approximately.

Abstract: An after-body assembly for an aeroengine, the assembly comprising an annular part (60) made of metallic material secured to the aeroengine and an after-body part (20) made of ceramic matrix composite material, the after-body part (20) being mounted on the annular part (60) by resiliently flexible fastener tabs (70) and having a first end (71) fastened to the annular part (60) and a second end (72) fastened to the upstream portion of the after-body part (20). Each fastener tab (70) includes an axial abutment element (720) that extends radially from the second end (72) of the tab and having at least a portion thereof facing the first end (71). The fastener tab (70) also includes a radial abutment element (721) at the second end (72) of the tab, the radial abutment element (721) at least partially overlying the first end (71).

Abstract: A part made of ceramic matrix composite material has fiber reinforcement of carbon or ceramic fibers and a majority-ceramic sequenced matrix having first matrix layers made of crack-deflector material alternating with second matrix layers made of ceramic material. An interphase coating is interposed between the fibers and the matrix, and the interphase coating adheres to the fibers and to the matrix, and is formed of at least one sequence constituted by a first elementary layer made of carbon, possibly doped with boron, surmounted by a second elementary layer made of ceramic. The outer elementary interphase layer of the coating is a ceramic layer having an outer surface formed by ceramic grains of size lying essentially in the range 20 nm to 200 nm, with the presence of grains of size greater than 50 nm conferring roughness on the outer surface ensuring mechanical attachment with the adjacent matrix phase.

Abstract: An assembly comprising first and second parts made of composite material held one against the other by at least one fastener system comprising a bolt having a flat head from which there extends a threaded portion, and a nut having a flat head from which there extends a shank including tapping suitable for co-operating with the threaded portion of the bolt. The head of the bolt bears against a countersink formed in the first part. The head of the nut bears against a countersink formed in the second part. The fastener system is suitable, during axial expansion of the fastener system, for causing each head to tilt towards the countersink in which it is housed.

Abstract: A fastener device for fastening a hollow part is made up of two mutually facing walls to at least one structural part. The device comprises a one-piece body of metal material presenting two main faces extending longitudinally between first and second ends of the body. Each main face includes a bearing portion in the vicinity of the first end of the body. The bearing portion is for being pressed against an inside surface of a respective one of the two walls of the hollow part, with each bearing portion including a fastener orifice for receiving a fastener member. The bearing portions are separated from each other by a slot extending from the first end of the body and over a determined depth within the body.

Abstract: Single-airfoil vanes each having an inner platform, an outer platform, and an airfoil are obtained by three-dimensionally weaving a fiber blank in a single piece, by shaping the fiber blank to obtain a single-piece fiber preform, and by densifying the preform with a matrix to obtain a vane of composite material forming a single piece with inner and outer platforms incorporated therein. A plurality of vanes is assembled together at an intermediate stage of densification to form a multi-airfoil composite material guide vane sector for a turbine nozzle or a compressor diffuser and the assembled-together vanes are bonded together.

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 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 process for preparing a monolithic catalysis element includes a fibrous support and a catalytic phase supported by the fibrous support and also the monolithic catalysis element. The process includes the steps of preparing a porous coherent structure based on refractory fibers; preparing a substrate including the porous coherent structure and nanocarbon supported by the porous coherent structure in the body thereof; and grafting to the substrate, by ? interaction, of at least one aromatic compound containing in its chemical formula, at least one aromatic ring, and at least one function chosen from acid catalytic functions, basic catalytic functions, metallic precursor functions, functions that can be converted in situ into metallic precursor functions, and mixtures thereof.

Abstract: The method comprises: using chemical vapor infiltration to form a first continuous interphase on the fibers of a fiber structure made of refractory fibers, the interphase having a thickness of no more than 100 nanometers; impregnating the fiber structure with a consolidation composition comprising a carbon or ceramic precursor resin; forming a fiber preform that is consolidated by shaping the impregnated fiber structure and using pyrolysis to transform the resin into a discontinuous solid residue of carbon or ceramic; using chemical vapor infiltration to form a second continuous interphase layer; and densifying the preform with a refractory matrix. This preserves the capacity of the fiber structure to deform so as to enable a fiber preform to be obtained that is of complex shape, while nevertheless guaranteeing the presence of a continuous interphase between the fibers and the matrix.

Abstract: A triggered-stroke actuator with its piston being held stationary in an initial position prior to triggering. The piston (13) is installed in the body (12) facing propulsion means (15) and a locking arrangement (19) that includes a latch (30) and at least one flexible tongue (23) attached to the periphery of the piston and having a hook (25) engaged with an internal abutment, the latch being moved at the beginning of triggering.

Abstract: The main subject of the present invention is a process for processing a paste (5) containing a solid charge (C) with a view to extracting at least one part of said solid charge (C). Said process comprises continuously: mixing, in a mixer (8), said paste (5) with a liquid solvent (3), a solvent for said at least one part of said solid charge (C), with a view to dissolving, at least partially, said at least one part of said solid charge (C) in said solvent (3); recovering, after said mixing, a biphasic system (15) comprising, on the one hand, a solution (3?) enclosing at least one fraction of said at least one part of said solid charge (C), dissolved in said solvent (3), and on the other hand, a solid residue (5?) of said paste (5); and then, separating said solution (3?) and said solid residue (5?) of said paste (5).

Abstract: A turbine nozzle or a compressor diffuser includes sectors made of CMC material, each having an inner platform, an outer platform, and airfoils. An abradable material support ring is made up of sectors, each presenting upstream and downstream attachment tabs. Each inner platform presents on the inside an upstream hook and a downstream hook, and the abradable material support ring is supported by the nozzle or the diffuser by mutually engaging without fastening together firstly the end portions of the upstream attachment tabs and the upstream hooks and secondly the end portions of the downstream attachment tabs and the downstream hooks.

Abstract: A rotor includes a disc, on which are fixed vanes, and platforms between these vanes. The rotor is particularly remarkable in that the platforms are fixed securely and tightly to the disc. To this end, the disc includes between two successive vanes an upstream stop projecting axially from the upstream surface, and each platform includes: a plate, a retaining groove extending axially and in which the upstream stop of the disc is engaged, an axial stop bearing axially against the upstream surface of the disc.

Abstract: A turbine rotor includes a plurality of blades of composite material comprising fiber reinforcement densified by a matrix. Each blade comprises a blade body extending between an inner end having a blade root and an outer end forming the tip of the blade. The rotor also includes outer platform elements of composite material comprising fiber reinforcement densified by a matrix, each outer platform element including an opening in which the outer end of a blade is engaged. The portion of the outer end of each blade that extends beyond the outer platform element includes a slot or a notch for receiving a locking element.