Abstract: A method optimizing a composite material blade profile for a rotor wheel of a turbine engine, and a blade including a tang compensated by the method. The method includes: compensating a blade airfoil by subdividing the airfoil into slices, and for each airfoil slice and a predetermined rotation speed of a disk of the wheel, calculating centrifugal force applied to the slice, calculating an aerodynamic force moment acting on a bottom section of the slice, and calculating shift values to be applied to a center of gravity of the slice to cancel the aerodynamic force moment; and compensating the blade tang by calculating centrifugal force applied to a blade portion situated beyond the airfoil neck, calculating an aerodynamic force moment acting on a bottom section of the blade tang, and calculating shift values to be applied to a center of gravity of the blade tang to cancel the aerodynamic force moment.

Abstract: A space propulsion module for fitting to spacecraft is provided. The space propulsion module includes a solid propellant chemical thruster including a main body, and at least one electric thruster. The at least one electric thruster is mounted on main body of the solid propellant chemical thruster.

Abstract: A space vehicle (1), in particular a satellite or a probe, capable of executing high-thrust maneuvers or high specific impulse maneuvers. According to the invention, the space vehicle (1) includes at least one solid-propellant chemical thruster (10-14) and at least one electric thruster (20-24).

Abstract: A method of fabricating a composite material part, the method including making a consolidated fiber preform, the fibers of the preform being carbon or ceramic fibers and being coated with an interphase; obtaining a consolidated and partially densified fiber preform, the partial densification comprising using chemical vapor infiltration to form a first matrix phase on the interphase; and continuing densification of the fiber preform by infiltrating an infiltration composition containing at least silicon and at least one other element suitable for lowering the melting temperature of the infiltration composition to a temperature less than or equal to 1150° C.

Abstract: A method of fabricating a composite material part comprises fiber reinforcement densified by a matrix. The method comprises the following steps: making a fiber fabric by weaving yarns having an initial mean fiber percentage; and densifying the fiber fabric with a matrix. The fiber fabric is subjected, prior to densification, to one or more jets of water under pressure so as to reduce the mean fiber percentage in the fabric to a value lying in the range 20% to 45%.

Abstract: A part including a substrate in which at least a portion adjacent to a surface of the substrate is made of a refractory material containing silicon, is protected by an environmental barrier formed on the surface of the substrate and having at least a self-healing layer containing a rare earth silicate. The self-healing layer is formed: for at least 90 mol %, by a system constituted by 30 mol % to at most 80 mol % of at least one rare earth silicate RE2Si2O7, RE being a rare earth, and at least 20 mol % to 70 mol % of manganese oxide MnO; and for at most 10 mol %, by one or more oxides other than MnO, having a eutectic point with SiO2 less than or equal to 1595° C.; the self-healing layer presenting a liquid phase having a self-healing function at least throughout the temperature range 1200° C. to 1400° C., while conserving a majority solid phase.

Abstract: A thermochemical treatment installation includes a reaction chamber, at least one gas inlet, and a gas preheater chamber situated between the gas inlet and the reaction chamber. The preheater chamber has a plurality of perforated distribution trays held spaced apart one above another. The preheater chamber also includes, between at least the facing distribution trays, a plurality of walls defining flow paths for a gas stream between said trays.

Abstract: A turbine engine blade made of composite material including fiber reinforcement obtained by three dimensionally weaving yarns and densified with a matrix, the blade including an airfoil and a blade root forming a single part. The blade root includes two opposite lateral flanks that are substantially plane and that are clamped between two independent pads made of composite material, which pads are fastened against the lateral flanks of the blade root to form a blade root that is bulb-shaped.

Abstract: A loader device is arranged for densifying porous preforms of stackable shape by means of directed stream chemical vapor infiltration in a reaction chamber of an infiltration oven. The device comprises a support tray, a first stack having a plurality of bottom rings arranged on the support tray and a plurality of injection orifices, a second stack comprising a plurality of top rings and a plurality of discharge orifices extending between the outer periphery and inner periphery of each ring. The device includes a first non-porous wall corresponding to the porous preforms and arranged on the support tray inside the bottom rings of the first stack, and a second non-porous wall corresponding to the porous preforms extending between the bottom ring situated at the top of the first stack and the top ring situated at the top of the second stack.

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 method of treating silicon carbide fibers comprises phosphating heat treatment in a reactive gas so as to form a coating around each fiber for protection against oxidation. The coating comprises a surface layer of silicon pyrophosphate crystals and at least one underlying bilayer system comprising a layer of a phosphosilicate glass and a layer of microporous carbon.

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.

Abstract: A method of fabricating a composite material casing for a gas turbine engine, the method including making an outer shroud including a platform and a flange, making an inner shroud of smaller diameter than the outer shroud and including a platform and a flange, making a plurality of casing arms, each including a blade that is terminated at each radial end by a respective platform, arranging a plurality of openings in the respective platforms of the shrouds, each opening serving to receive a platform of a casing arm, and assembling the casing arms with the outer shroud and with the inner shroud by inserting the platforms of the casing arms in the openings of the shrouds. A composite material casing is obtained by such a method.

Abstract: A thermostructural composite material part including carbon or ceramic fiber reinforcement densified by a matrix having at least one thin portion in which: the thickness of the part is less than 2 mm, or indeed less than 1 mm; the fiber reinforcement is made as a single thickness of multilayer fabric made of spread yarns having a weight of not less than 200 tex; the fiber volume ratio lies in the range 25% to 45%; and the ratio between the number of layers of the multilayer fabric and the thickness in millimeters of the part is not less than four.

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 spray device (100) for spraying a liquid (L), the device comprises a tank (10) containing the liquid (L) for spraying, at least one liquid ejector member (20) in communication with said tank (10), and a pyrotechnic gas generator (30) for pressurizing the liquid inside said tank and propelling it under pressure out from said tank. According to the invention, in at least one mode of operation, the ejector member (20) is in communication with the gas generator (30) in such a manner as to enable it to be fed with the gas generated by said generator (30).

Abstract: A lightning protector device for laying on a structure that is to be protected the device comprises: a surface coating including at least one conductive paint layer. A plurality of electrically conductive elements is arranged in spaced-apart manner on the structure, and the elements are in contact with the conductive paint layer. A protective coating is arranged on the surface coating and comprises a material that is thermally insulating and electrically conductive. The protective coating covers the electrically conductive elements in part.

Abstract: A turbine engine vane is made of composite material comprises a hollow airfoil with an internal passage extending along its entire length, an inner platform, and an outer platform. The airfoil is extended on the outside of the outer platform by an upstream attachment portion and a downstream attachment portion for mounting the vane in a casing. The attachment portions are formed by an attachment extending from the outer longitudinal ends of the pressure side wall and the suction side wall of the airfoil with continuity of the fiber reinforcing texture of the composite material between the walls and the attachment tabs.

Abstract: A method for obtaining solutions that contain 1,2,4-triazole-5-one (OTA) in concentrated sulphuric acid, includes using 3-amino-1,2,4-triazole (ATA) as a precursor of OTA. There is also provided a method for preparing 3-nitro-1,2,4-triazole-5-one (4) (ONTA) from the solutions.

Abstract: A substantially cylindrical gas-generating pyrotechnical monolithic block has a thickness no lower than 10 mm, an equivalent diameter no lower than 10 mm, and a porosity lower than 5%; and a composition, given as weight percentages, which contains, for at least 94% of the weight thereof: +77.5% to 92.5% of guanidine nitrate, +5% to 10% of basic copper nitrate, and +2.5% to 12.5% of at least one inorganic titanate with a melting temperature higher than 2100 K.