Abstract: A repaired nickel-based superalloy substrate that has applied thereon a nickel-based polycrystalline repair alloy comprising 0.03-2.5 weight % hafnium, 0.003-0.32% boron, 0.02-0.16% yttrium and 0.007-0.35% zirconium. The present invention further provides a repaired single crystal alloy substrate that has applied thereon a repair alloy wherein the repair alloy's composition is similar to or the same as the single crystal alloy composition except that the repair alloy additionally comprises at least one grain boundary strengthener element and at least one element that enhances oxidation resistance.

Abstract: A method for fabricating articles of high-temperature aluminum alloys having a compressional strength of at least 20 kg/mm.sup.2 at temperatures of 300.degree. C. or greater, is disclosed. The method comprises the steps of: (a) forming a porous preform from particles of a first aluminum alloy via cold-pressing, the preform having the shape and dimension of the aluminum alloy article to be fabricated; (b) squeeze-casting a molten second aluminum alloy into void spaces of the porous preform to form an aluminum composite containing the first aluminum alloy, which serves as a reinforcement phase, dispersed in the second aluminum alloy, which serves as a matrix phase; (c) wherein the molten second aluminum alloy is cast at such temperatures so as to cause a surface of the first aluminum alloy particles to melt and thereby form a strong bonding with the second aluminum alloy.

Abstract: A biaxially textured article includes a rolled and annealed, biaxially textured substrate of a metal having a face-centered cubic, body-centered cubic, or hexagonal close-packed crystalline structure; and an epitaxial superconductor or other device epitaxially deposited thereon.

Abstract: An improved method is described for restoring the mechanical properties to carbide-containing Co-based superalloy gas turbine components which have been exposed to high temperatures and pressures for extended periods of time. The method includes solution heat treating to 2250.degree.-2300.degree. F. for one to twelve hours to dissolve complex carbides, and aging at approximately 1965.degree.-1975.degree. F. for two to twenty four hours. The rejuvenated components exhibit excellent high temperature creep properties.

Abstract: The invention relates to a process for material treatment with diode radiation, especially laser diode radiation. To match the radiation profile to the treatment process, the process is so carried out that radiation emitted from a multiplicity of diodes is directed with a predetermined radiation profile upon the treated region of the workpiece and that a change in the intensity distribution in the radiation profile is effected by controlling the diode output power.

Abstract: A ceramic thermal barrier coating layer for a superalloy article is caused to adhere to the superalloy article by applying platinum to the superalloy article and heat treating at a temperature of 1100.degree. C. to 1200.degree. C. for one hour. This causes aluminum to diffuse from the superalloy article into the platinum to form a platinum enriched outer layer which generally includes a platinum enriched gamma phase and a platinum enriched gamma prime phase. An alumina layer is formed between the platinum enriched outer layer and a ceramic coating. The platinum enriched gamma phase and the platinum enriched gamma prime phase in the outer layer reduces the migration of transition metal elements to the ceramic coating to enable a very pure alumina layer to be formed.

Abstract: Disclosed is a process for the preparation of an alloy having excellent corrosion resistance and wear resistance, which comprises subjecting a powdery mixture comprising a powder of at least one matrix metal selected from the group consisting of Fe-based alloys, Co-based alloys and Ni-based alloys and a vanadium carbide powder to a heat treatment, wherein by repeating fusion and re-fusion by a heat treatment using a heat source having a high energy density, a phase of uniform and fine vanadium carbide particles is recrystallized and/or redeposited in the matrix metal phase.

Abstract: A coated article includes a superalloy substrate, an intermediate bond coat and a thermal barrier coating. The bond coat may include a platinum aluminide layer underlying a thin oxide layer. The thin oxide layer may include alumina. The coated article has high strength and durability at high temperatures over extended periods of time and thus is especially useful in the form of, e.g., a turbine blade or turbine vane.

Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate. Articles formed by the disclosed processes are described, including three-dimensional objects.

Abstract: Energy, such as from one or more lasers, is directed at the surface of a substrate to mobilize and vaporize a constituent element (e.g., carbide) within the substrate (e.g., steel). The vaporized constituent element is reacted by the energy to alter its physical structure (e.g., from carbon to diamond) to that of a composite material which is diffused back into the substrate as a composite material. An additional secondary element, which can be the same as or different from the constituent element, may optionally be directed (e.g., sprayed) onto the substrate to augment, enhance and/or modify the formation of the composite material, as well as to supply sufficient or additional material for fabricating one or more coatings on the surface of the substrate. The process can be carried out in an ambient environment (e.g., without a vacuum), and without pre-heating or post-cooling of the substrate.

Abstract: An improved method is described for repairing Co-base superalloy gas turbine engine components by applying a mixture of base alloy powder and base alloy powder with a melting point depressant to the surface of the component and heating at 2250.degree.-2300.degree. F. to diffuse the melting point depressant isothermally into the base alloy. A protective coating is then applied, during which a heating cycle which ages the base material is used. The resultant component has high temperature creep properties which are significantly better than achieved using the prior art process. The same temperature cycle is also useful in the initial heat treatment of Co-base superalloys, and can also be used for rejuvenation of components which have experienced extensive exposure to engine operating conditions.

Abstract: A method for producing a hydrogen-absorbing alloy electrode including a step of treating the surface of a hydrogen-absorbing alloy. The surface treatment is applied to hydrogen-absorbing alloy having ununiform distortion of 3.5.times.10.sup.-3 or less by using only an acid solution whose pH value is between 0.5 and 3.5.

Abstract: A method of preparing metal surfaces for thermally applied coatings by electrical discharge, which method controllably provides greater roughness for increased mechanical coating adhesion, avoids carbon deposits and is more economical to use. The method comprises melting and rapidly solidifying globules of the metal surface by spark erosion, the spark erosion occurring by incidence of an electrical discharge between an electrode and the metal surface closely spaced thereto, the spacing having an electrolyte with plasma forming capabilities, the discharge resulting from application of an electrical current to the electrode with a DC voltage in the range of 60-85 volts and amperage in the range of 50-110 amps, the current being pulsed on for periods of 150-300 micro seconds per spark.

Abstract: A bearing blank is cast or machined of cast iron to a configuration near a final shape of a desired bearing element. A first surface of the bearing blank, corresponding to a sliding surface of the desired bearing element, is remelted while other portions of the bearing blank remain in a solid state. The remelted first surface is quenched such that fine particles of iron carbide precipitate in a remelted zone having an increased hardness and a decreased presence of graphite particles. A bearing element having a core portion composed of cast iron and an integral first surface portion including a precipitate of fine iron carbide particles, and having greater hardness and lesser incidence of graphite particles than the core portion, is also described.

Abstract: A method and apparatus for re-flow of multi-layer metal bumps. A multi layer metal bump structure is surrounded by an oxygen poor environment. The topmost layer of the metal bump structure is heated by using infrared light for a predetermined time. The infrared light has a wavelength which is selected such that the top layer is heated more than the underlying layers.

Abstract: A process for remelting metal surfaces, in particular, camshafts, using a laser. The invention shortens the cycle times and further increases cost-effectiveness by not requiring remelting in a plurality of steps. The process uses a laser beam which is focused to a rectangle. The length of the beam spot extends over the entire width of the workpiece surface of the cam. The power density and relative speed are set in order to achieve the desired remelting depth.

Abstract: Composite parts of Ni-Ti alloys joined to a different metal have a melt forged structure obtained through the reactive fusion of both metals, initiated by the fusion of at least one metal bordering on the joint interface and the application of pressure; a hot forged structure of Ni-Ti alloy obtained through softening the alloy at high temperature and applying pressure on the Ni-Ti alloy side of the joint; and a hot forged structure of the different metal obtained by softening the metal at high temperature and applying pressure on the different metal side of the joint.

Abstract: This invention relates to a method to selectively mitigate intergranular stress corrosion cracking (IGSCC) by rapid quench melting through the use of a pulsed laser. Such methods of the type, generally, mitigate reactor pipe cracking by rapidly melting the sensitized material to redissolve chromium carbide and then rapidly cooling the sensitized material such that corrosion cracking can be avoided.

Abstract: A cobalt base, high temperature brazing alloy having a composition, by weight of:______________________________________ Nickel from about 8.5% to about 12.5% Chromium from about 24% to about 40% Tungsten from about 0% to about 9% Carbon from about 0.03% to about 0.6% Boron from about 0.01% to about 3.5% Silicon from about 1.0% to about 11% Manganese up to about 2% Cobalt Balance ______________________________________is provided for use in the repair of Co-base turbine component superalloys.

Abstract: Ni-Ti intermetallic compounds are produced by subjecting a laminate of Ni foils and Ti foils to a rolling for thickness adjustment and then to a diffusion heat treatment at multistages within a particular temperature range for a particular time.

Abstract: A method of strengthening an aluminum casting by modifying qualities of a specified part thereof comprises the steps of forming a weld overlay on the specified part using powders made of heat resisting element and remelting the specified part, now overlaid with the layer of heat resisting alloy layer, using high density energy.

Abstract: An apparatus for zone melting a thin semiconductor film comprises an first laser for heating the thin semiconductor film, at least one additional laser for heating an insulating substrate, a first temperature detecting device for detecting the temperature of a melted portion of the thin semiconductor film, and a second temperature detecting device for detecting the temperature of a solidified portion of the thin semiconductor film. The apparatus further comprises a first controller for controlling an output of the first laser so as to maintain the temperature of the melted portion in a first predetermined temperature range, and a second controller for controlling an output of the additional laser so as to maintain the temperature of the solidified portion in a second predetermined temperature range.

Abstract: NiAl is preheated to a temperature between 1530.degree. C. and 1638.degree. C. causing some of the aluminum to evaporate along the faying surfaces thereby forming a glazed layer of nickel rich self-generated filler metal. The glazed faying surfaces are placed in contact, heated to 1530.degree. C. to 1570.degree. C., and pressed together to form a fusion weld.

Abstract: The present invention relates to a method for granulating a stream of molten metal which falls from a launder or the like, down into a liquid cooling bath contained in a tank. The metal stream divides into droplets in the liquid cooling bath and the droplets solidify and form solid granules. The cooling liquid has substantially uniform flow across the tank in a direction that is substantially perpendicular to the falling metal stream. The flow of cooling liquid has a velocity of less than 0.1 m/sec. The distance from the outlets of the launder to the surface of the liquid cooling bath is kept less than 100 times the diameter of the metal stream measured as the metal stream leaves the launder.

Abstract: Surface-coated components, such as contact pieces for vacuum switches, are produced by means of the method by melting open the surface of a metallic substrate (1) in a local area (15) by an energy flow (12) and combining an additive (8) with the melted-open material of the local area (15). It is intended to produce components with large areas with small outlay in apparatus by means of this method. This is attained by the following steps: Prior to melting open the local area (15), the substrate (1) is pre-heated to a temperature considerably above room temperature, but below its melting temperature. After pre-heating, the local area (15) on the surface of the substrate is melted open and the additive (8) is applied to the substrate surface in the form of a loose powder layer (10).

Abstract: A method for improving the corrosion resistance of a zirconium-based material in an acid environment. A laser beam is scanned across the entire surface of the material to cause surface melting of the material. A rapid self-quenching is provided by the underlying substrate. Homogeneous material formed during solidification of the molten pool improves the corrosion resistance. Alloy enriched diffuse regions, i.e., tin and iron, develop parallel to each other and the periphery of the edge of the melt pool. In this manner, the laser surface melting removes the intermetalics by dissolving the precipitates, thus removing the source of localized corrosion. This greatly reduces the capability of the iron to act anodically to cause the zirconium to ionize, disassociate from the matrix, and migrate into the acid solution.

Abstract: Methods for synthesizing solid-state crystalline alloys and products made therefrom are disclosed. Plural repeat units, each comprising an ordered sequence of superposed layers of preselected solid-state reactants, are formed superposedly on a surface of a solid substrate to form a modulated composite of the reactants. The layers comprising a repeat unit are controllably formed to have relative thicknesses corresponding to the stoichiometry of a preselected solid compound found on a phase diagram of the reactants. Each repeat unit also has a repeat-unit thickness no greater than a critical thickness for a diffusion couple of the reactants, where the repeat-unit thickness is preferably less than or equal to about 100 .ANG.. The modulated composite is then heated to an interdiffusion temperature lower than a nucleation temperature for the reactants for a time sufficient to form an amorphous alloy of the reactants having a stoichiometry corresponding to the preselected solid compound.

Abstract: A method for producing a densified layer on the surface of a porous material having gas-containing voids which includes: (1) heating the outer surface of the porous material to cause localized removal of the gas contained in the voids so that the voids coalesce and form surface-connected channels, and (2) deforming the surface of the porous material to close the surface-connected channels so that a distinct, densified layer is formed at the surface of the porous material. The method is particularly applicable to the production of lightweight structural components.

Abstract: A multimetallic article of manufacture comprising a body (40) of a first metallic material with discrete regions (65) therein of a second metallic material is manufactured by the in situ alloying of a third material with the first material. The alloying is performed by depositing the third material at locations on the body where the first material is melted by an energy beam (45) such as a carbon dioxide laser or electron beam.

Abstract: The surface of a metal workpiece is remelted by a heat producing energy beam so as to form a molten metal layer thereon. While remelting the surface, a magnetic field is generated coaxially with the energy beam and is applied across the molten metal layer so as to cause the heat energy to flare and, thereby, produce a Lorentz force in the molten metal layer. By the Lorentz force, the molten metal is agitated. The heat energy and magnetic field are oscillated, or reciprocally moved, relative to the surface so as to cause a flow of the molten metal from the edges of the molten metal layer toward the center, thereby providing a uniform chilled layer thickness.