Abstract: A fiber reinforced thermoplastic propeller is attached to a metallic rotor by an integral shank at the base of the propeller. By virtue of the manufacture of the shank and the propeller as an integral construction, improved transmission of centrifugal forces especially where the propeller and hub have greatly different cross-sections can be effected while simultaneously reducing weight. Attachment of the shank to the hub is made through a connection by which pre-stress can be applied to the propeller to assist in resistance of lateral impact force.

Abstract: A method of producing a dispersion-hardened metal alloy in which oxide particles are distributed uniformly in the metal matrix. The oxide particles, in finely divided form, are added to a solution of the metal along with a deglomerating agent so as to be dispersed in the solution as a colloid. The colloid suspension is then atomized and reduced to form a powder of the alloy with the oxide particles uniformly dispersed therein.

Abstract: A method including embedding a porous silicon ceramic compact, or workpiece, in a powder which is not sinterable at the process temperature, and subjecting the powder and embedded compact to heat and pressure in a hot isostatic press. The powder transmits the pressure to the compact. The powder may be the same material as the compact, except without a sintering agent, or the powder may be graphite powder. The grain size of the powder is between 2 .mu.m and 50 .mu.m. The powder and embedded compact are placed in a container prior to hot pressing; the container may be made of thin sheet metal or of quartz glass.

Abstract: A ceramic preform is coated with a layer of amorphous carbon and is then hot-isostatically compressed to form the desired ceramic part. The layer of carbon can then be removed.

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 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 piston arrangement including a hollow piston, a piston pin extending within the piston, an intermediate abutment within the piston supporting the pin between its ends, and a transmission member, e.g., a connecting rod, engaging the pin on each side of the intermediate abutment. The intermediate abutment may be supported by the circumferential wall of the piston, or by the piston head, and may be formed as one piece with the piston. The transmission member may have a forked end for engaging the piston pin, the intermediate abutment being between the arms of the fork. The piston pin may be two separate aligned pins each having an end located within the intermediate abutment. The piston, intermediate abutment, piston pin, and transmission member may all be formed of a ceramic material.

Abstract: The present invention provides a method for encapsulating a ceramic moulding, preferably a silicon ceramic moulding such that the encapsulated mouldings can be subjected to hot isostatic pressing without causing the pressure-transfer medium to penetrate into the pores of the moulding. Encapsulation is achieved by first evacuating the moulding, then filling it with nitrogen gas and thereafter immersing it in a silicon (Si) melt. In a preferred aspect the moulding is filled with nitrogen gas under positive pressure. Once the silicon melt has been deposited, pressure can be allowed to act on it externally.

Abstract: A multiple-layer wall is provided for a hollow body to sustain high thermal and mechanical loads and to afford adequate thermal insulation. The wall has, on the inside, a heat and/or wear resistant ceramic inner layer and, surrounding it, a preferably prestressed retaining layer of fiber reinforced plastic. An intermediate layer of a thermally insulating ceramic material can also be provided. The wall can also have a retaining layer of metal. At least the retaining layer is shrink-fitted. The retaining layer of metal and/or the intermediate layer moreover can be deposited by a sintering process. Prestressing is achieved also by the shrinkage resulting from the sintering process. As a result of prestressing, the inner layer, when under internal pressure, comes under substantially no circumferential tension or under circumferential compression only. The wall is used especially with precombustion chambers of Diesel engines or with cylinder barrels or internal combustion engines.

Abstract: A blank is molded from a powdery mixture of silicon, .alpha.-silicon nitride, and a sintering agent. The blank is nitrided to nitride the silicon content of the blank, and thereafter the blank is subjected to hot isostatic pressing. The silicon content of the original powdery mixture is between 5% and 60% by weight of the mixture, and the sintering agent, which may be an oxide, is present in the original powdery mixture in the range between 0.1% and 10% by weight. The nitriding is carried out in a nitrogen atmosphere at a temperature between 1100.degree. C. and 1600.degree. C. The nitriding may be carried out in two stages, first at a temperature between 1050.degree. C. and 1400.degree. C., and then at a temperature above the melting point of silicon.

Abstract: A high-temperature, extremely high-speed ceramet composite blade comprising a ceramic blade jacket seated from above on a metallic core having a crossweb near its upper end for securing the jacket on the core by one or more metallic retaining pins extending through the crossweb and secured to the core. A head on each bolt is located within a chamber formed above the cross-web and surrounded by the radially projecting end of the blade jacket. A porous abradable coating is secured to the head of the bolt and substantially fills the chamber. The coating projects slightly beyond the end of the blade jacket and is supplied and permeated with cooling air via a cooling duct extending through the retaining pin and metallic core.

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 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: Precombustion chamber construction in a cylinder head of a diesel engine utilizing ceramic material to increase resistance to thermal stresses. A space is provided between the precombustion chamber construction and the cylinder head at least at the main combustion chamber of the diesel engine, and one or more ceramic bodies are shielded from the metal cylinder head and any other metal by thermal insulation to minimize thermal stresses and enable combustion in the precombustion chamber to take place at a higher temperature whereby the power/weight ratio and the efficiency of the engine are improved. The precombustion chamber construction in one embodiment is composed of axially successive parts, and at least the part nearest the main combustion chamber is made of the ceramic material and shielded as indicated.

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.

Abstract: A finished ceramic airfoil is provided having within it a lining of thermal insulation and a fusible core having the desired contour of the metal core of the turbine blade. A casting mold is provided around the airfoil. The fusible core is melted and removed, leaving a cavity in the airfoil surrounded by the insulation lining. The cavity is filled with molten metal which is allowed to solidify to form the metal core of the turbine blade.

Abstract: For encapsulating a ceramic molded member for high-temperature isostatic pressing (HIP), a generally porous coating of glass and/or ceramic is applied on the molded member of ceramic and sintered under a vacuum into a pressure-tight capsule encompassing the molded member.