Abstract: The present invention relates to a process for the self-regulated production as a function of the demand, under submerged conditions, of a gas (G), said gas (G) being generated by a chemical reaction between a liquid (L) and a solid (S) (hydrogen generated by hydrolysis of a metal hydride, for example) and not being polluted between the generation thereof and the delivery thereof. The present invention also relates to a device suitable for the implementation of said process.

Abstract: A vibration damper between outer platforms of adjacent composite-material blades of a turbine engine rotor wheel, the damper including a peg having a substantially spherical portion at each of its two ends, and two hollow inserts for being received in tangential cavities that are provided facing each other in outer platforms of two adjacent composite-material blades of a turbine engine rotor wheel, each spherical portion of the peg coming to bear with point contact against the inside of one of the inserts.

Abstract: A system for in-flight attitude control and side-force steering includes a thruster body and a plurality of valves capable of generating side thrusts put into communication with the thruster body. The valves are arranged in two sets of valves spaced apart from each other towards the front and towards the rear of the thruster body in substantially symmetrical manner relative to the center of gravity of the vehicle situated on a longitudinal axis (A) of the vehicle. Each set comprises a first pair of valves generating thrust in opposite directions along axes that are not in alignment and are parallel to a first axis, and a second pair of valves generating thrust in opposite directions along axes that are not aligned and are parallel to a second axis. The first and second axes are distinct and perpendicular to the longitudinal axis of the vehicle.

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 vibration damper between outer platforms of adjacent composite-material blades of a rotor wheel of a turbine engine, the damper including a strip for inserting lengthwise in tangential cavities that are formed facing each other in the outer platforms of two adjacent composite-material blades of a turbine engine rotor wheel.

Abstract: A paste kneading device includes an oblong barrel, two shafts arranged parallel within the barrel, being held and driven at their first ends, defining an upstream end, by a drive device, two screws each formed by threads carried by the shafts, each screw having a transport section carrying a main thread to cause the paste to advance along the two screws, and an outlet orifice formed in the wall of the barrel to discharge the kneaded paste, the kneading device further including a holder device to hold each shaft at its second end, defining a downstream end, and enabling the shaft to rotate freely, the holder device including, for each shaft, a first portion secured to the shaft and a second portion secured to a cap end portion of the barrel, the cap end portion being removable and the first and second portions being configured to engage and disengage freely.

Abstract: A layout of a blisk includes two inserts housed between the bulb of the blade and the wall of a groove in a disk to compensate for variations in inclination between the overhanging faces of the groove and the upper faces of the bulb at their central part. This construction makes it possible to select blades for which upper faces of the bulb are slightly inclined relative to the radial direction, which facilitates their construction from a composite material.

Abstract: The present invention relates to a method for obtaining borazane, said method being suitable for obtaining borazane containing a low level of impurities. The borazane (obtained by reaction of at least one ammonium salt with at least one alkali and/or alkaline earth metal borohydride) in solution in THF is selectively precipitated with a non-solvent. The precipitated borazane can further be purified by selective dissolution. The borazane obtained after selective precipitation and dissolution contains less than 1% by weight of impurities and/or does not exhibit exothermic decomposition in the solid state with a temperature range of the endothermic melting peak above 110° C.

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: The invention relates to an assembly comprising first and second parts made of composite material and held against each other by at least one fastener system comprising a rivet having a flat head from which there extends a shank having an enlarged end, and a washer co-operating with the enlarged end of the shank of the rivet, the head of the rivet bearing against a countersink formed in the first part, the washer bearing against the second part. On its face remote from its face bearing against the second part, the washer presents a portion of conical shape. The washer also has a central countersink with the enlarged end of the shank of the rivet pressing thereagainst.

Abstract: A turbine ring assembly includes a ring support structure and a plurality of ring sectors, each including a single piece of ceramic matrix composite material. Each ring sector includes a first portion forming an annular base with an inside face defining an inside face of the turbine ring and an outside face from which there extends two tab-forming portions including ends that are engaged in housings in the ring support structure. The ring sectors present a section that is substantially ?-shaped and the ends of the tabs are held without radial clearance by the ring support structure. The tabs can have a free length in meridian section that is not less than three times their mean width.

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, forming a single part with incorporated inner and/or outer platform.

Abstract: A refractory material withstanding high temperatures in an oxidizing medium contains at least hafnium boride and tantalum boride, hafnium and tantalum being present in the refractory material exclusively in compound form.

Abstract: A method of assembling together by brazing first and second parts made of composite material, each of the first and second parts having an assembly face for brazing with the assembly face of the other part, the method including making at least one perforation in the assembly face of the first part; interposing capillary elements between the assembly faces of the first and second parts made of composite material; placing the first and second parts facing each other while inserting a peg in each perforation of the first part; placing a brazing composition in contact with a portion of the capillary elements; and applying heat treatment to liquefy the brazing composition so as to cause the molten brazing composition to spread by capillarity between the assembly faces of the composite material parts.

Abstract: A method for fabricating a turbomachine blade or vane of composite material including fiber reinforcement densified by a matrix is disclosed. The method includes: 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 triggered-stroke actuator presenting at least one additional pyrotechnic charge for adapting its resistance against return to vary in desired manner. According to the invention, at least one additional pyrotechnic charge (21a-21c) is situated in a housing communicating with the expansion chamber (24) of the actuator (11).

Abstract: The present invention relates to an electric switch having a hollow body defining a cavity, an actuator, and a slide mounted in said cavity. Under the action of the actuator, the slide is suitable for passing from a first position, in which at least one conductive portion of the slide is electrically connected via permanent breakable electrical junctions to at least two primary electrically-conductive studs that lead laterally into said cavity to a second position in which at least one of said primary electrically-conductive studs is no longer electrically connected to said conductive portion of the slide.

Abstract: A method of treating ceramic fibers based on metal carbide, the method including a first reagent gas heat treatment performed with at least one first reagent gas of the halogen type that chemically transforms the surface of the fiber to obtain a surface layer constituted mainly of carbon, and a second reagent gas heat treatment performed with at least one second reagent gas that eliminates the surface layer formed during the chemical transformation.

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.