Abstract: The instant invention describes a method of repairing heat-resistant alloy parts which have been cracked or otherwise damaged due to exposure of combustion gases from a turbojet engine. The method includes chemically cleaning the surface of the part to remove the layer of contaminants and subjecting the part to a thermochemical treatment to thoroughly clean the cracks and other narrow, damaged areas. A diffusion brazing process is then utilized to fill the cracks or damaged areas.

Abstract: A diffusion brazing process for superalloy parts is performed on the one hand by the interposition between the pieces to be joined of a joining layer having a composition close to that of the parts and containing a "fluxing" element, which renders it more readily meltable, and on the other hand, a heat treatment effecting the brazing by the melting of the joining layer and its resolidification, by the diffusion of the flux. The process of the invention is characterized, particularly in view of permitting the use of a joining layer of a greater thickness than that of the layers used in the known diffusion brazing processes, in that said joining layer consists of a mixture of a superalloy powder and an alloy powder containing the flux.

Abstract: A gas turbine blade in which are provided inter alia two chambers for the circulation of cooling fluid, lying in proximity to the leading and trailing edges of the blade respectively, two conduits disposed respectively between the first chamber and the leading edge and between the second chamber and the trailing edge, and apertures connecting each conduit to the chamber nearest to it. The blade is produced by diffusion-brazing two half-blades together. The chambers are formed in part in one, and in part in the other, half blade. In order to produce the conduits and apertures by means of grooves engraved in the facing surface of the two half blades, the interface of the two half-blades divides said conduits and apertures in two.

Abstract: The invention concerns the manufacture of a porous product based on nickel, hromium, tungsten, molybdenum, iron, cobalt or an alloy of these metals. The porous product is characterized on one hand by the fact that it comprises 85 to 99.5% by weight of the base material and 15 to 0.5% of a fusible auxiliary metal chosen from among tin, indium, gallium, germanium and mixtures and alloys of these metals and, on the other hand, by the fact that the base material is in the form of elementary particles such as powders, fibers or chips, bonded to each other by means of diffusion brazing.

Abstract: The invention concerns a process for the manufacture of pieces comprising least one part of an abradable, porous material, which may be integral with a support part. The process is characterized in that synthesis by diffusion of the abradable material is effected in a mold, at least one part of which constitutes the support piece.

Abstract: The procedure according to the invention, for joining together stainless el or superalloy parts, consists of placing an interface material, chosen from a group containing tin, indium, antimony, gallium and germanium or consisting of a combination of these elements, between the contacting surfaces of the parts, and then subjecting the entire assembly to heat treatment in a controlled atmosphere at a temperature greater than 900.degree. C. but in every case less than the solidus point of the parts to be joined together. If the parts are not of the same nature, the lower solidus point will be the limiting temperature. The treatment lasts as long as necessary to permit the interface material to migrate and compounds or solutions to form, ensuring the diffusion brazing of the parts to be joined. The parts are held together under a moderate pressure during at least part of the treatment, so as to maintain their positions relative to each other and to promote the diffusion without causing deformation.

Abstract: A procedure for joining parts by brazing-diffusion byEffecting a primary machining on the parts to be assembled in order to prde reservoirs for filling metal,Arranging a strip between the parts or deposit a coating on one of the parts,Filling the filling metal reservoir with a metal powder,Holding the parts together and providing pressure on the surfaces to be joined by means of screws or the equivalent,Placing the assembly within an enclosure containing a controlled atmosphere which is heated to cause, first, the filling metal to flow and, second, diffusion to take place, thenPerforming a secondary machining to eliminate the retaining screws and if possible the reservoirs.