Societe Nationale D'etude Et De Construction De Moteurs D'aviation

Snecma

Jacques Lesgourgues

Robert Lucien Martinou

Jean-Paul Fournes

Jacques P Tirole

Bernard A Blanchet

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.

Method of repairing heat resistant alloy parts

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.

Diffusion brazing process for pieces of superalloys

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.

Gas turbine blade with chamber for circulation of cooling fluid and

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.

Novel porous body and process for its preparation

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.

Process for the manufacture of a piece comprising at least one porous

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.

Method of joining metal parts

A procedure for joining parts by brazing-diffusion by

Growing community of inventors

Corbeil, France

Jacques Lesgourgues