Abstract: A corrosion inhibited fuel mixture includes a hydrocarbon fuel, at least one vanadium composition, and a yttrium composition. The concentration of the yttrium composition in the mixture provides at least a stoichiometric amount of yttrium for a substantially complete reaction between the yttrium and V.sub.2 O.sub.5 formed from the vanadium composition when the mixture is burned. The yttrium and V.sub.2 O.sub.5 react to form YVO.sub.4. One particular yttrium composition useful as a hydrocarbon fuel soluble, water stable vanadium corrosion inhibitor incorporates a yttrium ester having at least four carbon atoms and a hydrocarbon fuel soluble chelating agent that includes 2,4-pentanediene. The complex has a molar ratio of 2,4-pentanediene to yttrium of up to 5:1.

Abstract: Superalloy articles are made more oxidation resistant by a process which includes heat treating the article in the presence of foreign chemical species, at a temperature at which the foreign chemical species reacts with and modifies any oxide film present on the article surface. The heat treatment is best carried out at a temperature above the gamma prime solvus temperature of the article and below the incipient melting temperature of the article. Alternatively, the heat treatment may be carried out within the range defined by the incipient melting temperature of the article and about 150.degree. C. below the incipient melting temperature of the article. At such temperatures the foreign chemical species reacts with and modifies the oxide film on the article surface. Sulfur is then able to diffuse through such modified film, and a more oxidation resistant component is produced.

Abstract: A method of bonding a plurality of articles together with an organic adhesive by using a primer that provides increased crack propagation resistance without the use of organic solvents. The method comprises reacting aluminum, titanium silicon, iron, or zirconium with HBr or HI. The reaction product is oxidized with a water soluble oxidizing agent to form a hydrosol. The hydrosol is then mixed with an organofunctional silane to form the primer. The primer is applied to the surface of an adherend prior to the application of adhesive.

Abstract: A method of making a polymeric composite wherein the polymeric composite is more oxidatively stable. The method comprises reacting aluminum, titanium, silicon, or zirconium with HBr or HI.sub.2, oxidizing the reaction product to form a hydrosol and applying the hydrosol to the fiber surface prior to incorporation in a polymeric composite. The composite exhibits greater oxidative stability as it is exposed to temperatures of about 100.degree. C. to about 900.degree. C.

Abstract: A method of coating a fiber resulting in a more oxidative resistant fiber. The method comprises mixing metal alkoxides and basic metal carboxylates in amounts such that the metal alkoxides are substantially water soluble. The basic metal carboxylate has the formula:R'--CO.sub.2 M'(OH).sub.n.zH.sub.m Xwhere(i) R' is an organic radical;(ii) M' is any metal that has a valence of 3 or 4;(iii) X is BO.sub.3.sup.-, SO.sub.4.sup.=, Cl.sup.-, NO.sub.3.sup.-, R"CO.sub.2.sup.-, where R" is an organic radical;(iv) n and m correspond to the valence of (M'-1) and X respectively; and(v) Z has a value sufficient so that said R'--CO.sub.2 M'(OH).sub.n is substantially water soluble.A layer of the solution is applied to the fiber and the fiber is exposed to a temperature sufficient to form an oxide surface. The fibers can be used to make polymeric composites. Fibers having the above-described coating are impregnated with a resin, stacked in layers and exposed to pressure and optional heat.

Abstract: A method of bonding a plurality of articles together with an organic adhesive by using a primer that provides increased crack propogation resistance without the use of organic solvents. The method comprises reacting aluminum, titanium, silicon, iron, or zirconium with HBr or HCI. The reaction product is oxidized with a water soluble oxidizing agent to form a hydrosol. The hydrosol is applied to the surface of a metal article prior to the application of adhesive.

Abstract: An amorphous hydrated metal oxide primer for adhesively bonded articles results in a bond resistant to crack propagation. A plurality of articles at least one of which is ceramic are bonded to one another through a layer of polymeric adhesive. The ceramic article has a layer of amorphous hydrated metal oxide formed by applying and subsequent hydrolysis of a layer comprising M.sub.x OR.sub.y or mixtures thereof. In the formula M.sub.x OR.sub.y, x is 1, y is 3 or 4, M is any metal capable of forming a stable alkoxide and R is an organic radical. The bonded joint is preferably made by applying to a surface of at least one ceramic article a layer of M.sub.x OR.sub.y described above. The ceramic article having a layer of metal alkoxide is exposed to moisture and a temperature of about 25.degree. C. to about 300.degree. C. and adhesive is placed in contact with and between the ceramic article and other article.

Abstract: Metal coated ceramic particles are bonded to a metallic substrate in a high temperature sintering process. A low viscosity binder solution containing fine metallic particulates is first applied to the substrate surface. Then, the coated ceramic particles are disposed upon the substrate surface, and the binder solution and the metal particulates therein are attracted by capillarity into regions of point contact between the ceramic particles and the substrate surface. During a subsequent high temperature sintering operation, the metal coating on the ceramic particles diffuses into the metal substrate, and the metallic particulates melt and solidify to bridge the gap between the substrate and ceramic particles.

Abstract: Techniques are described for the formation of an abrasive surface layer on an article. The surface layer is characterized by a single layer of particles which are evenly spaced apart, in a high density arrangement, within a metallic matrix. In the deposition of the particles on the article, a vacuum is drawn through a perforated plate, wherein the location of each perforation corresponds to the desired location of one particle on the article surface. The vacuum holds one particle over each perforation in the plate, then the plate is positioned over the article and the vacuum level adjusted so that the particles fall onto the article. The matrix is then deposited by plasma arc spraying a superalloy powder. The invention is particularly suited to the formation of an abrasive layer on the tip surface of a blade used in a gas turbine engine.

Abstract: An amorphous hydrated metal oxide primer for fibers incorporated into fiber reinforced polymeric matrix composites result in composites having wet strength retention. The layer of amorphous hydrated metal oxide is formed by depositing on the fiber and subsequent hydrolysis of a layer of M.sub.x OR.sub.y where x is 1, y is 3 or 4, M is any metal capable of forming a stable alkoxide and R is an organic radical. Fiber reinforced polymeric matrix composites are preferably made by applying a layer of M.sub.x OR.sub.y to the fiber where x is 1, y is 3 or 4, M is any metal capable of forming a stable alkoxide and R is an organic radical. The fiber having a layer of metal alkoxide is exposed to moisture and a temperature of about 25.degree. C. to about 125.degree. C., impregnated with a resin and stacked in a mold. The stacked impregnated fibers are then pressed with optional heat resulting in a composite having wet strength retention.

Abstract: The present invention relates to a two-component acrylic modified polyester adhesive. Said adhesive comprising a first component having an acrylic modified polyester and about 0.1% to about 0.5% by weight of a peroxide, and a second component comprising an organometallic acid salt in a polymerizable organic monomer. In addition, a method of using said adhesive is disclosed.

Abstract: An amorphous hydrated metal oxide primer for adhesively bonded articles results in a bond resistant to crack propagation. A plurality of articles at least one of which is metal are bonded to one another through a layer of polymeric adhesive. The metal article has a layer of amorphous hydrated metal oxide formed by applying and subsequent hydrolysis of a layer of M.sub.x OR.sub.y. In the formula M.sub.x OR.sub.y, x is 1, y is 3 or 4, M is any metal capable of forming a stable alkoxide and R is an organic radical. The bonded joint is preferably made by applying to a surface of at least one metal article a layer of M.sub.x OR.sub.y wherein x is 1, y is 3 or 4, M is any metal capable of forming a stable alkoxide and R is an organic radical. The metal article having a layer of metal alkoxide is exposed to moisture and a temperature of about 25.degree. C. to about 125.degree. C. and adhesive is placed in contact with and between the metal article and other article.

Abstract: A method of making a fiber reinforced polyimide matrix composite article is described. The method comprises preparing an aqueous solution of a polyimide matrix material containing sufficient nonionic surfactant such that the surface tension of the solution is about 35 dynes per centimeter or lower. The solution is then coated onto the fibers and the coated fibers formed into tapes. The tapes are then dried, cut into predetermined shapes and laid one on top of the other to form a lay-up. The lay-up is then densified under heat and pressure forming a polyimide matrix composite article.

Abstract: The present invention relates to a two-component acrylic modified polyester adhesive. Said adhesive comprising a first component having an acrylic modified polyester and about 0.1% to about 0.5% by weight of a peroxide, and a second component comprising an organometallic acid salt in a polymerizable organic monomer. In addition, a method of using said adhesive is disclosed.

Abstract: The present invention is directed toward novel high flash point fluids useful in the calibration of jet engine fuel controls. These compositions comprise about 70 weight percent to about 90 weight percent of dodecane and about 10 weight percent to about 30 weight percent of a material selected from the group consisting of organic esters, ethers and acids. Said fluids have flash points which are greater than 170.degree. F. (76.7.degree. C.) making calibration of the fuel controls safer.

Abstract: A process for producing binderless, single phase bulk carbon or graphite articles having a fibrillar microstructure comprising the steps of assembling a plurality of polymer fibers into a preselected pattern, subjecting them to a temperature and pressure sufficient to cause heat distortion flow and concomitant self-bonding of contiguous fibers and pyrolyzing the fibers in a nonoxidizing atmosphere.

Abstract: This invention relates to an anaerobic adhesive and method of making the same, comprising the reactive product of a glycidyl acrylate and a hydroxyl containing polyester. The reaction between the glycidyl acrylate and the polyester typically takes place in the presence of a radical inhibitor and an acid accelerator with oxygen present. The resulting adhesive is a single component, structural adhesive which will cure in an anaerobic environment.

Abstract: The present invention is directed toward a process for making water soluble polyimide resin systems. The process comprises preparing a solution of a polyamic acid in an organic solvent, adding water to the solution to cause the polyamic acid to precipitate, filtering the precipitated acid, washing the precipitated acid with water to remove the organic solvent and then reacting the washed acid with a water soluble amine forming the water soluble amine salt of the polyamic acid. This polyamic acid salt may then be converted to the polyimide by heating. These water soluble polyamide systems allow for safer application of polyimide coatings to substrates.

Abstract: A dielectric film with improved dielectric strength, mechanical strength, high temperature utility, and moisture resistance is described comprising the reaction product of 1, 2, 3, 4 butane tetracarboxylic acid, a multifunctional amine of the formula: ##STR1## and at least one diamine, the multifunctional amine constituting at least 5% of the total amine equivalents of the reactants. The polyimide dielectric film can be cast out of aqueous solution on a mold release surface.

Abstract: A corrosion inhibited fuel mixture includes a hydrocarbon fuel, at least one vanadium composition, and a yttrium composition. The concentration of the yttrium composition in the mixture provides at least a stoichiometric amount of yttrium for a substantially complete reaction between the yttrium and V.sub.2 O.sub.5 formed from the vanadium composition when the mixture is burned. The yttrium and V.sub.2 O.sub.5 react to form YVO.sub.4. One particular yttrium composition useful as a hydrocarbon fuel soluble, water stable vanadium corrosion inhibitor incorporates a yttrium ester having at least four carbon atoms and a hydrocarbon fuel soluble chelating agent that includes 2,4-pentanedi.?.e.!..Iadd.o.Iaddend.ne. The complex has a molar ratio of 2,4-pentanedi.?.e.!..Iadd.o.Iaddend.ne to yttrium of up to 5:1.