Abstract: A gas turbine engine (10) incorporates a fuel manifold (12) that distributes fuel to fuel injectors (14) that are mounted to a support casing (16). When a problem is encountered within the fuel injector (14), the problem injector (14) may be disconnected from the fuel manifold (12) and removed without disturbing the fuel manifold (12).

Abstract: A process for fabricating a composite article is disclosed. A surface of a preconsolidated fiber reinforced glass matrix composite structure is pretreated to promote adhesion to the surface, a mass of fiber-containing uncured resin is molded in contact with the pretreated surface and the resin is cured to consolidate a fiber reinforced resin matrix composite structure and simultaneously bond the resin matrix composite structure to the glass matrix composite structure. A composite article fabricated by the above process is also disclosed.

Abstract: Processes for making metal prototype parts are described. The key steps of the invention include: making a computer aided design (CAD) file of the prototype part; modifying such file a first time to produce a file of a first mandrel upon which the part will be formed; modifying such file a second time to produce a second mandrel upon which a metal anode will be formed, the anode and first mandrel then being used in an electroplating process to form the prototype. Stereolithographic techniques are preferred for making the mandrels out of polymeric materials.

Abstract: This invention relates to abrasive layers for use in the gas turbine industry. The preferred embodiment of the invention comprises nickel coated, yttria doped silicon nitride particulates dispersed within a nickel base superalloy matrix which is substantially free of oxides. The layer is formed using low pressure plasma spray processes.

Abstract: A method for making a fiber reinforced crosslinked polyimide matrix composite article that is substantially free of internal voids and surface blisters is disclosed. The method includes heating a fiber prepreg under vacuum to remove volatile impurities and volatile reaction products from the prepreg and subsequently curing the prepreg to form the article.

Abstract: A method for applying ceramic coatings using electron beam--physical vapor deposition techniques is described. The method includes the step of introducing the anionic constituent of the ceramic into a coating chamber and confining the anionic constituent about the component to be coated during the coating cycle.

Abstract: A process for forming a diffusion coating to the surface of a metal article. The process is particularly adapted for forming diffusion aluminide coatings on metal blades and vanes used in gas turbine engines. According to the invention, halide vapor is caused to react with a source of aluminum to form an aluminum rich halide gas. This gas then reacts with the part surface to form the aluminide coating. A key aspect of the invention relates to the timing of the reaction between the halide vapor and the source of aluminum.

Abstract: Methods are described for forming an yttrium enriched aluminide coating on the surface of a nickel or cobalt base superalloy article. In one preferred embodiment, a pack mixture for forming the coating consists essentially of, by weight percent, 5-35 of an Al-Y-Si alloy, 1-20 CoI.sub.2, balance Y.sub.2 O.sub.3.

Abstract: A ceramic core molding composition, which includes alumina fibers, zircon, and fumed silica in an amorphous silica base, reduces shrinkage and shrinkage stresses during the core production process. Cores produced utilizing the disclosed composition and method exhibit an improved resistancce to macrocracking over conventionally produced cores.

Abstract: A process for fabricating a composite article is disclosed. A surface of a preconsolidated fiber reinforced glass matrix composite structure is pretreated to promote adhesion to the surface, a mass of fiber-containing uncured resin is molded in contact with the pretreated surface and the resin is cured to consolidate a fiber reinforced resin matrix composite structure and simultaneously bond the resin matrix composite structure to the glass matrix composite structure. An external flap for a gas turbine engine fabricated by the above process is also disclosed.

Abstract: Methods for selectively applying a diffusion aluminide coating to the surface of a metal article while keeping other article surfaces free of the coating are described. The method includes the steps of injection molding a mixture of materials onto the surfaces which are to be kept free of coating; the material comprises solid particles effective in preventing deposition of the coating onto the surfaces and a moldable amorphous thermoplastic resin; it contains no volatilizable solvents. The mixture is applied to the article surface to a thickness of about 5 millimeters. It is useful in pack diffusion as well as vapor phase diffusion aluminide coating operations.

Abstract: An improved process for hot isostatically pressing metal castings is described. The key feature of the invention relates to the continual increase in the magnitude of the applied pressure during the cycle, and the absence of holds at pressure after achieving the maximum process pressure.

Abstract: A fiber reinforced glass matrix composite article and a process for fabricating a fiber reinforced glass matrix composite article are disclosed. The article has an outer layer with selectively oriented continuous fiber reinforcement and an inner core having randomly oriented discontinuous fiber reinforcement. The process utilizes the hydrostatic pressure provided by injection molding of the discontinuous fiber reinforced core to fully consolidate the continuous fiber reinforced outer layer.

Abstract: Sputtering techniques are utilized to form an aluminum rich diffusion coating on the surface of a superalloy substrate. The coating contains additions of oxygen active elements, such as yttrium, and the coating has an outward diffusion aluminide microstructure obtained by carrying the sputtering process out at temperatures in the range of about 1,010.degree.-1,150.degree. C.

Abstract: The anisotropy typically observed in single crystal nickel base superalloys is reduced by intentionally adding certain small amounts of carbon, boron, zirconium or hafnium, either individually or in combination, to the alloy composition.

Abstract: A protective coating system for superalloys is described. The coating is an yttrium enriched aluminide, and can be formed by aluminizing an MCrAlY coated superalloy, wherein during the aluminizing process, aluminum diffuses completely through the MCrAlY coating and into the substrate. The coating system exhibits desirable oxidation resistance and resistance to thermal fatigue cracking.

Abstract: Nickel base superalloys having properties equal to or better than alloys currently used in gas turbine engines are described. Preferably, the alloys of the present invention are cast into single crystals.

Abstract: This invention relates to an improved method for electroplating a layer of nickel onto titanium base alloy substrates. It is particularly useful in electroplating a layer of nickel onto titanium alloys which contain refractory metal elements, such as the alloy Ti-8Al-1V-1Mo. The method includes the steps of etching the surface of the substrate with a solution containing hydrofluoric acid and hydrochloric acid, followed by electroplating the etched surface in a nickel sulfamate solution.

Abstract: A protective coating system for superalloys is described. The coating is an yttrium enriched aluminide, and can be formed by aluminizing an MCrAlY coated superalloy, wherein during the aluminizing process, aluminum diffuses completely through the MCrAlY coating and into the substrate. The coating system exhibits desirable oxidation resistance and resistance to thermal fatigue cracking.

Abstract: This invention relates to an improved method for electroplating a layer of nickel into titanium base alloy substrates. It is particularly useful in electroplating a layer of nickel onto titanium alloys which contain refractory metal elements, such as the alloy Ti-8Al-1V-1Mo. The method includes the steps of etching the surface of the substrate with a solution containing hydrofluoric acid and hydrochloric acid, followed by electroplating the etched surface in a nickel sulfamate solution.