Abstract: A method for fabricating turbine engine blade or vane made of composite material includes: performing three-dimensional weaving to make a single-piece fiber blank; shaping the fiber blank to obtain a single-piece fiber preform having a first portion forming a preform for at least a blade/vane airfoil, at least one second portion forming a preform for an inner part of a blade/vane inner platform or for an outer part of a blade/vane outer platform, and at least one third portion forming a preform for an outer part of a blade/vane inner platform or for an inner part of a blade/vane outer platform; and densifying the fiber preform with a matrix to obtain a composite material blade, and forming a single piece with an inner and/or outer platform(s) incorporated therein.

Abstract: A turbomachine blade made of composite material including a fiber reinforcement obtained by three-dimensional weaving of yarns and densified by a matrix, includes a first portion constituting an airfoil and a blade root. The first portion constitutes a single part with at least one second portion constituting a blade inner platform, the blade then lacking a blade anti-tilting wall, or a blade anti-tilting wall, the blade then lacking a blade inner platform. The first portion also constitutes a single part with at least one third portion constituting a blade outer platform spoiler plate, the blade then lacking a blade outer platform wiper plate, or a blade outer platform wiper plate, the blade then lacking a blade outer platform spoiler plate.

Abstract: A turbomachine blade or vane is made of composite material including fiber reinforcement obtained by three-dimensional weaving of yarns and densified by a matrix. The blade or vane includes a first portion constituting at least an airfoil exhibiting two faces each connecting a leading edge to a trailing edge, the first portion forming a single part with at least one second portion present only on one of the faces of the airfoil, the second portion constituting a portion of at least one of the following elements: a flowpath delimiting outer portion of an inner platform, an inner portion of an inner platform, a flowpath delimiting inner portion of an outer platform, and an outer portion of an outer platform, the portions of the fiber reinforcement corresponding to the first and the second portions of the blade being at least partially mutually imbricated, with yarns of the first portion of the fiber reinforcement penetrating into the second portion of the fiber reinforcement.

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: 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 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: 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: 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: The invention relates to an electricity production system for feeding electrical energy to a device of an aircraft. The system comprises a generator for generating gaseous hydrogen from hydrogen in non-gaseous form, a main tank connected upstream to the generator and for containing gaseous hydrogen under a pressure substantially higher than atmospheric pressure, the gaseous hydrogen being produced by the generator, at least one fuel cell, an expander connected upstream to the main tank and downstream to the fuel cell(s), where upstream and downstream are defined relative to the flow direction of the hydrogen under normal conditions of operation of the system, and a control device that regulates the flow rate and the pressure of the gaseous hydrogen from the main tank to the fuel cell(s) via the expander.

Abstract: The triggered stroke actuator comprises a cylinder (12) housing a movable assembly constituted by a piston (13), a rod (16) projecting from one end of the cylinder (12), and a slidable element (17) that is movable inside the cylinder (12). The actuator also includes means for propelling the piston (13) in response to a trigger command, and a return braking arrangement. The return braking arrangement is constituted by at least one ball (18) housed in an annular cavity (19) defined by the inside surface of the cylinder (12) and by the slidable element (17), a return spring (22) connecting the slidable element (17) to the piston (13), and a link element (23) connecting the ball (18) to the piston (13). The ball (18) is positioned by the link element (23) in a first segment (20) of the annular cavity (19) when the return spring (22) is relaxed, and in a second segment (21) of decreasing radial extent when the return spring (22) is compressed.

Abstract: Pyrotechnic actuator in particular for lifting the hood of an automobile in the event of a collision with a pedestrian. The actuator comprises a return-braking arrangement (25) acting between the rod (17) and the body (13) of the actuator and having an inertial actuating threshold in order to brake the rod in return only if it is subjected to a force under a sufficient acceleration truly representative of a collision.

Abstract: A method of fabricating a composite-material turbomachine blade having platform incorporated therein includes separately making a blade platform element that includes rigidified fiber reinforcement and that has a shape close to that of a platform of the blade to be fabricated, with at least one opening being formed through the platform element. The opening has the shape of the profile of the airfoil of the blade to be fabricated. Three-dimensional weaving is used to make a flexible fiber blank as a single piece that includes blade airfoil-and-root preform portions. The platform element is engaged, via its opening, on the flexible fiber blank while deforming it so as to assemble the platform element with the fiber blank. The fiber blank is shaped together with the platform element assembled thereon to obtain a blade preform of a shape that is close to the shape of the blade to be fabricated. After shaping, the blade preform is consolidated in its shape in a shaper.

Abstract: The main subject of the present invention are solid compounds capable of generating hydrogen by a self-sustaining combustion reaction. Their composition comprises borazane and/or polyaminoborane and at least one inorganic oxidant, advantageously chosen from ammonium nitrate, alkali metal nitrates, alkaline-earth metal nitrates, metal nitrates, metal oxides, oxidants of the family of dinitramines and mixtures thereof. It also relates to the generation of hydrogen by self-sustaining combustion of at least one such compound.

Abstract: The invention relates to a method and to an autonomous device (10d) for injecting a fluid (F), that uses pyrotechnical means (1d). The invention can be used in particular for injecting a protection fluid (F) into a system that is subject to overheating (8d). The method is characterized in that it uses a thermally triggered charge (1d).