Abstract: A process for preparing a Ni-based superalloy cast article includes (a) preparing an alloy charge composed of from 1.4 to 4.4 wt. % of Cr, from 3 to 8 wt. % of Co, from 5 to 7.5 wt. % of W, from 4.8 to 7.5 wt. % of Re, from 6 to 9 wt. % of Ta, from 4.8 to 6 wt. % of Al, from 0.1 to 0.5 wt. % of Nb, from 0.8 to 1.8 wt. % of Hf, from 0.05 to 0.1 wt. % of C, from 0.01 to 0.05 wt. % of Y, from 0.005 to 0.15 wt. % of B, and balance Ni, wherein the sum of W+Re is about 12 wt. %, the sum of Al+Ta+Hf+Nb ranges from 13.6 to 15.6 wt. %, and the sum of W+Re+Ta+Hf+Nb ranges from 20.2 to 22.8 wt.

Abstract: A method for forming integral extensions on the end of directionally oriented, superalloy articles, such as airfoil blading members or other components used in gas turbine or other turbine engines. An extension is formed directly on an article by dipping a portion or end of the article into a molten bath of a compatible alloy, followed by withdrawal of the end under controlled conditions sufficient to cause an integral extension to solidify on the article. A ceramic mold is utilized over the dipped end of the article with a mold cavity that generally defines the shape of the extension to be formed. The mold may be formed in situ, or preformed and attached to the subject article. Extensions formed by the method of this invention have a microstructure that is continuous and compatible with that of the article. Such microstructures may include epitaxial growth of the extension from the microstructure of the article.

Abstract: Columnar grain and single crystal nickel base superalloys are heat treated to provide a damage tolerant microstructure. The microstructure contains large, irregularly shaped "barrier" .gamma.' particles interspersed in an ordered array of smaller cuboidal .gamma.' particles in a .gamma. phase matrix. The barrier particles interrupt the progression of cracks through the microstructure. The invention process includes solutioning the .gamma.' phase, cooling slowly to a temperature about 50.degree. F. to 150.degree. F. (28.degree. C. to 83.degree. C.) below the .gamma.' solvus temperature, further cooling at a rate of at least about 100.degree. F. (56.degree. C.) per minute to less than 1000.degree. F. (538.degree. C.), reheating to 1975.degree. F. to 2000.degree. F. (1079.degree. C. to 1093.degree. C.) and holding for about four to six hours, cooling at 100.degree. F. (56.degree. C.) per minute to less than 1000.degree. F. (538.degree. C.), and heating to 1600.degree. F..+-.25.degree. F. (871.degree. C..+-.14.

Abstract: In a heat treatment process for material bodies made of nickel base superalloys, in particular for monocrystals made of nickel base superalloys, the heat treatment of the material body comprises the following steps: annealing at 850.degree. C. to 1100.degree. C., heating to 1200.degree. C., heating to a temperature of 1200.degree. C.<T.ltoreq.1300.degree. C. at a heat-up rate of less than or equal to 1.degree. C./min, and a multistage homogenization and dissolution process at a temperature of 1300.degree. C..ltoreq.T.ltoreq.1315.degree. C.

Abstract: A nickel-base superalloy, in particular for the fabrication of large monocrystalline components, essentially comprises (measured in wt %): 6.0-6.8% of Cr, 8.0-10.0% of Co, 0.5-0.7% of Mo, 6.2-6.6% of W, 2.7-3.2% of Re, 5.4-5.8% of Al, 0.6-1.2% of Ti, 6.3-7.0% of Ta, 0.15-0.3% of Hf, 0.02-0.04% of C, 40-100 ppm of B. 15-50 ppm of Mg, the remainder being nickel with impurities. Carbides of Ta, Ti, and Hf, and Mg, and/or Mg--O--S compounds are concentrated along small angle grain boundaries of the superalloy.

Abstract: A method for manufacturing an aluminum alloy conductor for use at ultra low temperature which involves the steps of adding at least one of the metallic and semimetallic effective elements selected from the group consisting of B, Ca, Ce, Ga, Y, Yb and Th, in a total amount of 6 to 200 weight ppm, into a previously prepared molten high purity aluminum having a purity of not less than 99.98 wt % to thereby obtain a molten metal mixture; casting the molten metal mixture to thereby obtain a casting; subjecting the casting to extrusion working at 150.degree. C. to 350.degree. C. in an area reduction ratio of 1:10 to 1:150 whereby an extrusion worked product is formed; and annealing the extrusion worked product at a temperature of 250.degree. C. to 530.degree. C. for 3 to 120 minutes, whereby an aluminum alloy conductor for use at ultra low temperature is obtained.

Abstract: A method of making a single crystal or columnar grain superalloy casting comprises casting a superalloy in a mold wherein at least one of the mold and optional core comprises an oxygen-bearing ceramic, directionally solidifying the superalloy to form a single crystal or columnar grain superalloy casting, and solution heat treating the superalloy casting. The heat treatment is conducted under an atmosphere including a carbon-bearing gas, such as a carbon monoxide and inert gas mixture, wherein the carbon-bearing gas is present in an effective amount to reduce loss of carbon from the casting during the heat treatment. The heat treatment can be conducted prior to removal of all of the mold and core, if present, such as, for example, when the cast mold is in the as-knocked out condition wherein residual mold and/or core material is present on the casting. Alternately, the heat treatment can be conducted after removal of the mold and core, if present.

Abstract: A heat treatment and hot working method for producing a thin sheet of nickel base superalloy single crystals is described, wherein a single crystal preform of an alloy is first heat treated in vacuum at temperatures below the .gamma.' solvus temperature of the alloy in order to obtain an overaged .gamma.' microstructure in the preform, sized and surface ground in order to remove surface defects, and then preferably surrounded by plates and interlayers of refractory metal or alloy and parting agent coatings; the plates are then welded to form an enclosure and evacuated, preheated and soaked at 1093.degree. to 1150.degree. C. and rolled at roll speeds of about 0.12 to 0.25 rods in successive passes, at about 5 to 15% reduction per pass with reheating at the soaking temperature between successive passes, to a reduction in thickness of 50 to 75%; the plates are then removed and the preform is conditioned, repacked and successively rolled to preselected thickness.

Abstract: The aluminum conductor having increase of its electric resistivity kept small at ultra low temperature of 30.degree. K. or lower even after cyclic strain is given at ultra low temperature, by controlling the crystal structure of the high purity aluminum conductor with purity of 99.9-99.9999 wt % so as to consist of (i) a veritable single or a substantially single crystal consisting of a bundle of sub-grains which have their crystal axes in the same direction or in the directions within a couple of degrees of deviation as a whole which has a specific crystal axis of <111> or <100> or the crystal axes close thereto in the longitudinal direction of the aluminum conductor, or (ii) a polycrystal most of which grains have respective specific crystal axes of <111> and/or <100>, or the crystal axes close thereto with respect to each grain in the longitudinal direction of the aluminum conductor, and have specific grain size of 0.01 mm to 3.0 mm.

Abstract: A cyclic heat treatment for eliminating the tendency of moderately deformed superalloys to recrystallize is described. The superalloys are subjected to a temperature cycle including a period at a high temperature and a period at a low temperature. The resultant heat treated articles are resistant to recrystallization at temperatures above the gamma prime solvus temperature.

Abstract: A typical source of cadmium and tellurium is as a by-product of copper mining. Although attempts are made to remove impurities such as copper prior to commercially supplying them for forming material like cadmium telluride, cadmium zinc telluride and cadmium telluride selenide for use as a substrate to support electronic circuitry, processing during formation of the circuitry causes the impurities from the substrate to segregate into the circuitry, resulting in unacceptable electrical performance of the circuitry. A method for purifying the substrate prior to circuitry formation includes forming a sacrificial layer of mercury telluride or mercury cadmium telluride on the substrate, annealing the combination at elevated temperature with an overpressure of mercury and removing the sacrificial layer along with a contiguous portion of the substrate, if desired. The sacrificial layer may be formed by vapor phase type processes or even by liquid phase epitaxy.

Abstract: Unwanted recrystallization during heat treatment of a directionally solidified nickel alloy single crystal casting is prevented by chemical milling the part before heat treatment. Removal of a layer of as little as 0.013-0.050 mm thick, less than two percent of the part thickness, has been found effective.

Abstract: A crystal growth method for crystallizing an amorphous thin film comprises heat-treating an amorphous thin film having a region (I) with a predetermined film thickness and a region (II) with a larger film thickness than the region (I) and having a sufficiently small area so as to form only a single nucleus from which a single crystal is grown by solid phase growth at a temperature not higher than the melting point of the film.

Abstract: An austenitic steel comprising Ni of 9-30%, Cr of 10-23%, and Fe of at least 45%, is characterized in comprising enough Cr and Ni to form whole austenitic structure in the equilibrium diagram at 700.degree. C., having austenitic phase at room temperature, and the austenitic phase is a single crystal, and has superior resistance against stress. The austenitic steel preferably comprises C.ltoreq.0.1%, Si.ltoreq.1%, Mn.ltoreq.2%, Ni 9-15%, Cr 16-18.5%, and at least one of elements selected from the group of Mo 1-3%, Ti 0.05-1%, and Nb 0.1-1.5%. The alloy is useful as a material for members of a reactor core of a nuclear reactor.

Abstract: A nickel-base superalloy, particularly adapted for use in gas turbine engine single crystal blades and vanes is provided with a specific composition and heat treated in a particular manner to exhibit an improved balance of critical high temperature mechanical properties and resistance to oxidation and hot corrosion significantly superior to presently available alloys. In its broad form, the alloy composition comprises, by weight, 7-12% Cr, 1-5% Mo, 3-5% Ti, 3-5% Al, 5-15% Co, 3-12% W, up to 10% Re, 2-6% Ta, up to 2% Cb, up to 3% V, up to 2% Hf, the balance being essentially nickel and incidental impurities. Nickel-base superalloy single crystal articles formed of the alloy are described, as is the method, including heat treatment, employed to make the article.

Abstract: A method of producing an electrical conductor is described. The electrical conductor is made of an oxygen-free copper material having an oxygen content of not more than 50 ppm, wherein copper crystals constituting the copper material are giant crystals. These giant copper crystals are formed by heating the copper material in an inert atmosphere maintained at a temperature exceeding 800.degree. C., but below the melting point of copper for at least 15 minutes.