Abstract: A method for manufacturing components having thin walls of complex design by depositing a layer of metal or ceramic material on a shaped substratum. The resulting coated shaped bodies are then arranged inside an external envelope such that the shaped bodes represent the cavities to be incorporated in the component under manufacture whereas the coatings represent the walls surrounding the cavities. The envelope is then hermetically sealed, evacuated and upon evacuation, subjected to a hot compression operation. Thereafter, the envelope and the shaped bodies are at least partially removed by chemical or mechanical processes. Several layers of various materials and various chemical and physical properties can be deposited on the shaped bodies to form the walls.

Abstract: A seal between two machine parts for sealing separate spaces at different pressure from each other comprising a brush seal extending at an acute angle to a principal axis of at least one machine part for use in spatially constricted constructions with small clearances, particularly fluid-flow engines such as airplane jet engines, for sealing rotating or stationary parts.

Abstract: A method of producing a wear protection coating on a surface of a structural part of titanium or a titanium base alloy comprising applying a metallic nickel layer which adheres to the surface of the structural part and thereafter subjecting the thus coated structural part to a heat treatment to form diffusion layers of Ti.sub.2 Ni and TiNi.sub.3 between the titanium and the nickel. Thereafter, the layer of nickel alone or with the layer of TiNi.sub.3 is removed to leave the titanium part covered by a protection layer of the remaining diffusion layer.

Abstract: A thin-walled elastic envelope or mold element is arranged within a divisible outer supporting mold of porous material and a vacuum is applied to the outer supporting mold. Thereupon powdered metal or ceramic is introduced into the elastic mold element and the mold element is closed and pressurized to form a preform. The preform is then subjected to cold isostatic pressurization which is applied to the outer surface of the elastic mold element. Prior to the cold isostatic pressurization, the vacuum applied to the outer supporting mold is terminated and a vacuum is produced within the elastic mold element.

Abstract: A heat exchanger comprising a field of profiled tubes arranged in vertical columns and horizontal rows, each profiled tube being of oblong shape and, at least in part, surrounded by at least two supporting profile strips extending in the direction of fluid flow. The profiled strips of adjacent profiled tubes in a column are held at their ends in a well-defined position. Furthermore, the profile strips can rest directly or indirectly on other profile strips, adjacent thereto at the left or right, of adjacent profiled tubes. In this way, individual profiled tubes are longitudinally displaceable in an exact field arrangement and can compensate for changes in length.

Abstract: A mold comprising a core which is open at one end and has the negative contour of the workpiece and a sheet-metal outer container surrounding the core. High dimensional stability of the core, easy removability of the workpiece from the mold and a smoother surface of the workpiece are obtained by isostatic pressing of titanium powder in the spaces in the mold. The core consists, at least at its negative contour surface for the workpiece, of a high-temperature alloy, particularly one having a base of nickel or iron. This and the titanium powder material of the workpiece are neutral in chemical reaction and low in or free of diffusion with respect to each other upon the hot isostatic pressing. The core is in the form of a ring of segments surrounded by a solid holding ring.

Abstract: A non-contacting seal between a rotating part to be sealed and a stationary part, in which the rotating part includes a coaxial disk which is surrounded by a stationary collecting channel axially closely adjoining the disk but without contacting it. The collecting channel forms a spirally shaped hollow space in the circumferential direction of the rotating part, with a sealing medium return line connected to the hollow space within the area of enlargement of the hollow space. A seal, however, may also be installed between the rotating part and the fixed part.

Abstract: A liquid reservoir, such as an oil tank, for use in missiles or aircraft which are subjected to extreme flight attitudes. The reservoir has a wall rotationally symmetrical about the longitudinal axis of the reservoir, and the liquid content of the reservoir is rotated about the longitudinal axis to provide, by centrifugal force, a central space within the reservoir which is essentially free of liquid. Air is vented from the reservoir through a fixed vent located within the central space created when the liquid content is rotated.

Abstract: A method for the application or impregnation of a highly adherent heat-barrier layer on a metal substrate comprising effecting chemical vapor-phase deposition of zirconium dioxide as a heat-barrier layer with infiltration by finely granular zirconium dioxide in a metal felt. The vapor-phase deposition with infiltration of the metal felt can take place, in particular, from zirconium chloride, preferably within a temperature range between 550.degree. C. and 750.degree. C.

Abstract: A connection of the tubular ends of conduits or flow profiles which are associated with a cross-countercurrent matrix of a heat exchanger, and which are internally streamed through by a relatively cool gas (compressed air), to a suitably preperforated heat exchanger bottom of one or more manifolds formed for, respectively, the infeed or discharge of compressed air into or from the applicable heat exchanger matrix. In particular, the invention pertains to a method for the manufacture of such a connection.

Abstract: In a method for undetachably interconnecting discrete structural parts by means of a connecting or bonding material, the structural parts which are to be interconnected are arranged in an aligned manner in a hollow mold, and the interspaces between the hollow mold and the structural parts are filled with a sinterable metal powder. After the arrangement is heated to the sintering temperature of the metal powder, a sintered body results with at least partially embedded, rigidly interconnected structural parts, due to a diffusion bonding. Heat exchanger blocks may especially be produced according to such a method in a simple manner, without requiring that the separate structural parts must be pre-machined for an exact shape accuracy.

Abstract: A method of manufacturing molded articles of metal alloys, especially of nickel-base alloys, chromium-base alloys, titanium-base alloys, and dispersion-hardened alloys. A powder of the alloy, or a blend of powders of alloy constituents, is mixed with one or more plastics, selected from thermoplastics, duroplastics, and internal lubricants to form an injectionable granulate compound, the plastic content amounting to about 30% to 50% by volume. The compound is prepared by dissolving the plastic in a solvent which will not attack the base material of the alloy, and by blending it with the metal powder, after which the solvent is evaporated. The injectionable granulate compound is then injection molded to form a molded article. By heat treatment at 600.degree. C. or below in inert gas the plastic is eliminated from the molded article. The article is then sintered. To improve its strength, the article may subsequently be subjected to hot isostatic pressing.

Abstract: A valve for an internal combustion engine having mutually cooperating sealing surfaces, both of which are cylindrical. At least the movable valve member, carrying one of the sealing surfaces, is made of ceramic material. The movable valve member may be disk-shaped or have a bulbous or drop shape. The valve member may have a hollow cylindrical body reciprocable through a hole in a wall, a circumferentially arranged port in the body being selectively closed by moving the body into the hole.

Abstract: A heat exchanger with at least one main tube, closed off at one end, into which compressed air, which is to be heated, is admitted and, after being heated, is removed. The main tube has at least two channel guideways which are separated from one another in the longitudinal direction. U-shaped or curved compressed air lines project from the main tube and contact the hot gases. Each compressed air line is connected at one end to the channel guideway of the main tube into which compressed air is admitted, and at its other end with the channel guideway through which the heated compressed air is removed. The compressed air lines are formed primarily from hollow bodies, which extend in the direction of flow of the hot gas and which preferably are tapered at the inflow and outflow ends in order to aid the flow.

Abstract: A metal intermediate layer between two generally parallel thrust surfaces. At least one of the thrust surfaces is ceramic, and the surfaces are oblique to the direction of force tending to press the surfaces toward each other. The intermediate layer is formed by applying a metal powder suspension to at least one of the surfaces, and thereafter drying and if necessary heating the suspension to remove the non-metallic portion of the suspension. The surfaces may be faces of the blade root and slot, which accommodates the root, of a turbomachine.

Abstract: A thermocouple made of the silicon carbide and carbon. A carbon rod extends within a silicon carbide tube. The tube is closed at one end, and one end of the rod is fixed in a blind hole in the tube end to define the hot junction of the thermocouple, the hot junction thereby being located within the tube. An electrical insulator sealing ring closes off the opposite end of the tube. The tube is made by sintering a preform, the rod being within the tube, with one end in the blind hole, during sintering, so that the hole wall shrinks around the rod end.

Abstract: An annular sleeve surrounds a turbine rotor and is fixed to a stationary part, the sleeve being elastically deformable in a radial direction. A wear ring is carried by the sleeve, the wear ring being composed of segments arranged end-to-end circumferentially. The adjacent ends of the segments are spaced apart at all operating conditions of the turbine. The thermal expansions of the turbine rotor and of the sleeve and ring are so related that under operating conditions of the turbine, when the engine of which it forms a part is running, the sleeve thermally expands radially. The rate of thermal expansion of the stationary part is directly related to the rate of thermal expansion of the turbine rotor. Air leaving the compressor is directed against the sleeve and the stationary part carrying the sleeve. The wear ring and portion carrying the sleeve may be insulated. The sleeve may be mounted on a combustion chamber surrounding the turbine.

Abstract: An annular sleeve surrounds a turbine rotor and is fixed with respect to the turbine casing, the sleeve being elastically deformable in a radial direction. A wear ring is carried by the sleeve, the wear ring being composed of segments arranged end-to-end circumferentially. The adjacent ends of the segments are spaced apart when the turbine is cold or idling. The thermal expansions of the turbine rotor and of the sleeve and ring are so related that in one operating temperature range of the turbine the spaces between the adjacent ends of the ring segments close and the segment ends engage each other, and in a higher operating temperature range of the turbine the sleeve expands. Air leaving the compressor is directed against the sleeve and the stationary part carrying the sleeve. The wear ring and portion carrying the sleeve may be insulated. The sleeve may be mounted on a combustion chamber surrounding the turbine.

Abstract: A ceramic combustion chamber having air inlet ports and a double wall formation in the region of each inlet port. The two walls of the formation have a cavity between them which communicates with the inlet port. The double wall formation may be formed by an annular slot in the wall of the part. Alternatively, the double wall formation may be formed by two nested but spaced apart shells joined together at one end of the combustion chamber. The combustion chamber may be made by compressing ceramic powder in two steps to create a compact having an internal lost core or cores which are burned out, after which the ports are formed. Alternatively, the combustion chamber may be made by die casting ceramic powder around cores having the shape of the desired air inlet ports, after which the cores are burned out.

Abstract: Apparatus including a material reservoir, a tool having a mold cavity, and a cylinder having a plunger for pushing material received by the cylinder from the reservoir into the mold cavity. Equipment is provided for evacuating the reservoir, the mold cavity, and the cylinder. The reservoir is connected to the cylinder in a vacuum-tight manner. The evacuating equipment includes a vacuum pump and a vacuum reservoir, and valves permit optional connection of the material reservoir and the mold cavity to the vacuum pump or the vacuum reservoir. The volume of the vacuum reservoir is many times, i.e., 100 to 1000 times, greater than that of the mold cavity. A shutoff valve for disconnecting the mold cavity from the evacuating equipment is located in the immediate vicinity of the mold cavity. All the valves may be operated in a predetermined sequence by a control unit. The material reservoir may serve simultaneously as the vacuum reservoir.