Abstract: A turbine component includes: a metallic wall having opposed interior and exterior surfaces, the wall configured for directing a combustion gas stream in a gas turbine engine; and a metallic negative CTE structure rigidly attached to one of the surfaces

Abstract: Rhenium-free nickel based alloys are provided. More particularly, the alloys comprise preferred levels and ratios of elements so as to achieve good high temperature strength of both gamma matrix phase and gamma prime precipitates, as well as good environmental resistance, without using rhenium. When cast and directionally solidified into single crystal form, the alloys exhibit creep and oxidation resistance substantially equivalent to or better than rhenium-bearing single-crystal alloys. Further, the alloys can be processed by directional solidification into articles in single crystal form or columnar structure comprising fine dendrite arm spacing, e.g., less than 400 ?m, if need be, so that further improvements in mechanical properties in the articles can be seen.

Abstract: A method for treating a powder, includes: dry mixing the powder with an effective amount of a treating additive to distribute a layer of the treating additive on a surface of a particle of the powder, a primary particle size of the treating additive being smaller than an average particle size of the powder. An associated treated powder is also described.

Abstract: A cobalt-nickel base alloy is disclosed. The alloy includes, in weight percent: greater than about 4 % of Al, about 10 to about 20 % of W, about 10 to about 40 % Ni, about 5 to 20 % Cr and the balance Co and incidental impurities. The alloy has a microstructure that is substantially free of a CoAl phase having a B2 crystal structure and configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment. A method of making an article of the alloy includes: selecting the alloy; forming an article from the alloy; solution-treating the alloy; and aging the alloy to form an alloy microstructure that is substantially free of a CoAl phase having a B2 crystal structure, wherein the alloy is configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment.

Abstract: Gamma titanium aluminide intermetallic compositions (gamma TiAl intermetallics) based on the TiAl (gamma) intermetallic compound. The gamma TiAl intermetallics contain chromium and niobium, as well as controlled amounts of carbon that achieve a desirable balance in room temperature mechanical properties and high temperature creep capabilities at temperatures approaching and possibly exceeding 1600° F. (about 870° C.).

Abstract: Methods for casting a metallic material to form a component are described. The component can be a superalloy-containing turbine part, for example. The general method includes the step of pouring the metallic material, in molten form, into an investment mold; and then rapidly immersing the entire investment mold into a bath that contains a low-melting liquid coolant metal, so as to achieve substantially uniform, multi-directional heat transfer out of the molten material. The molten material that solidifies to form the component is characterized by a fine-grained, equiaxed grain structure. Related embodiments include the use of two ingots that constitute the superalloy material. One ingot includes the oxygen-reactive elements, and is prepared by a vacuum-melting technique. The other ingot includes the remainder of the elements, and can be prepared by a number of techniques, such as air-melting processes.

Abstract: A cobalt-nickel alloy composition is described, containing about 20% to about 28% cobalt; about 37% to about 46% nickel; at least about 6% chromium; aluminum; and at least one refractory metal. The total weight of cobalt, aluminum, and refractory metal in the composition is less than about 50% of the total weight of the composition. Moreover, the alloy composition comprises both a (Co, Ni)-gamma phase and an L12-structured (gamma prime) phase. Various components made from the cobalt-nickel alloy composition are also described. Examples include high-temperature machinery and devices, e.g., components of gas turbine engines.

Abstract: A high-temperature, high-strength, oxidation-resistant cobalt-nickel base alloy is disclosed. The alloy includes, in weight percent: about 3.5 to about 4.9% of Al, about 12.2 to about 16.0% of W, about 24.5 to about 32.0% Ni, about 6.5% to about 10.0% Cr, about 5.9% to about 11.0% Ta, and the balance Co and incidental impurities. A method of making an article having high-temperature strength, cyclic oxidation resistance and corrosion resistance is disclosed. The method includes forming a high-temperature, high-strength, oxidation-resistant cobalt-nickel base alloy as described herein; forming an article from the alloy; solution-treating the alloy by a solution heat treatment; and aging the alloy by providing at least one aging heat treatment at an aging temperature that is less than the gamma-prime solvus temperature, wherein the alloy is configured to form a continuous, protective, adherent oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment.

Abstract: A cobalt-nickel base alloy is disclosed. The alloy includes, in weight percent: greater than about 4% of Al, about 10 to about 20% of W, about 10 to about 40% Ni, about 5 to 20% Cr and the balance Co and incidental impurities. The alloy has a microstructure that is substantially free of a CoAl phase having a B2 crystal structure and configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment. A method of making an article of the alloy includes: selecting the alloy; forming an article from the alloy; solution-treating the alloy; and aging the alloy to form an alloy microstructure that is substantially free of a CoAl phase having a B2 crystal structure, wherein the alloy is configured to form a continuous, adherent aluminum oxide layer on an alloy surface upon exposure to a high-temperature oxidizing environment.

Abstract: Casting molds suitable for directional solidification processes using a liquid cooling bath include a graded facecoat structure on a mold body. The graded facecoat structure includes an innermost layer and a delamination layer, wherein the delamination layer fractures upon cooling of the molten metal so as to separate the mold body from the innermost layer, which remains in contact with or in close proximity to the metal being cast. Also disclosed are directional solidification processes.

Abstract: A coating process and system suitable for use on components subjected to high temperatures. The coating system includes an overlay coating of predominantly B2 phase rhodium aluminide (RhAl) intermetallic compound containing about 25 to about 90 atomic percent rhodium, about 10 to about 60 atomic percent aluminum, optionally up to a combined total of about 25 atomic percent of one or more platinum group metals chosen from the group consisting of platinum, palladium, ruthenium, and iridium, and up to about 20 atomic percent of the base metal and alloying constituents of the substrate. The RhAl intermetallic coating may serve as an environmental coating, a diffusion barrier layer for an overlying environmental coating, or both, with or without an outer ceramic coating.

Abstract: A method for preparing an article of a base metal alloyed with an alloying element includes the steps of preparing a compound mixture by the steps of providing a chemically reducible nonmetallic base-metal precursor compound of a base metal, providing a chemically reducible nonmetallic alloying-element precursor compound of an alloying element, and thereafter mixing the base-metal precursor compound and the alloying-element precursor compound to form a compound mixture. The compound mixture is thereafter reduced to a metallic alloy, without melting the metallic alloy. The step of preparing or the step of chemically reducing includes the step of adding an other additive constituent. The metallic alloy is thereafter consolidated to produce a consolidated metallic article, without melting the metallic alloy and without melting the consolidated metallic article.

Abstract: A component such as a turbine bucket or blade, and method for making the component, are presented. One embodiment is an article that comprises an airfoil casting portion comprising a plurality of integral regions, wherein the plurality of integral regions comprises a single-crystalline region and a columnar-grained region. Another embodiment is a method for fabricating an article. The method comprises providing a quantity of molten metal; providing a mold defining an airfoil portion having an axial direction and a transverse direction, wherein the airfoil portion of the mold comprises a single-crystal growth region and a columnar growth region disposed along the transverse direction from the single crystal growth region; introducing the molten metal into the mold; and solidifying the metal such that a solidification front progresses in the axial direction to produce an airfoil casting portion comprising a single-crystalline region and a columnar-grained region.

Abstract: Methods for making a reinforced refractory crucible for melting titanium alloys including providing a form, applying a facecoat to the form, the facecoat having at least one facecoat layer, applying a backing about the facecoat, the backing having at least one backing layer, applying at least one reinforcing element to at least a portion of the facecoat layer, the backing layer, or a combination thereof where the reinforcing element includes at least one composition selected from ceramic compositions, metallic compositions, and combinations thereof.

Abstract: A method for preparing an article of a base metal alloyed with an alloying element includes the steps of preparing a compound mixture by the steps of providing a chemically reducible nonmetallic base-metal precursor compound of a base metal, providing a chemically reducible nonmetallic alloying-element precursor compound of an alloying element, and thereafter mixing the base-metal precursor compound and the alloying-element precursor compound to form a compound mixture. The compound mixture is thereafter reduced to a metallic alloy, without melting the metallic alloy. The step of preparing or the step of chemically reducing includes the step of adding an other additive constituent. The metallic alloy is thereafter consolidated to produce a consolidated metallic article, without melting the metallic alloy and without melting the consolidated metallic article.

Abstract: A casting process and apparatus for producing directionally-solidified castings, and castings produced therewith. The process entails applying a facecoat slurry to a surface within a mold cavity to form a continuous solid facecoat on the surface, introducing a molten metal alloy into the mold cavity so that the molten metal alloy contacts the facecoat, and then immersing the mold in a liquid coolant to cool and solidify the molten metal alloy and form a casting of the metal alloy, during which an oxide layer forms on the casting surface. The facecoat is sufficiently adherent to the oxide layer such that at least a portion of the facecoat detaches from the mold surface and remains tightly adhered to the casting surface in the event the casting contracts during cooling. The facecoat contains at least 60 weight percent of a first phase of yttria, and the balance of the facecoat is a binder phase of an inorganic material.

Abstract: In one aspect, the present invention provides a subsurface heating device comprising: (a) a combustion conduit casing defining a combustion conduit; (b) at least two combustors disposed within the combustion conduit casing; (c) at least one fuel supply conduit; d) at least one oxygen supply conduit configured to supply oxygen to at least one combustor; and (e) a combustion product gas outlet. The at least two combustors are characterized by an inter-combustor distance of at least one thousand feet and a combustion power of at least 3.41 million BTU per hour. The at least one fuel supply conduit is configured to supply a combustible fuel to at least one combustor. Also provided in another aspect of the present invention, is a method for heating a subsurface zone.

Abstract: An article including a monolithic body including iron, cobalt, and nitrogen is provided. The monolithic body includes a matrix phase and a plurality of particles disposed within the matrix phase. The particles include a phase comprising nitrogen.

Abstract: A metallic article is prepared by first furnishing at least one nonmetallic precursor compound, wherein all of the nonmetallic precursor compounds collectively containing the constituent elements of the metallic article in their respective constituent-element proportions. The constituent elements together form a titanium-base alloy having a stable-oxide-forming additive element therein, such as magnesium, calcium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, and mixtures thereof. The stable-oxide-forming additive element forms a stable oxide in a titanium-based alloy. At least one additive element is present at a level greater than its room-temperature solid solubility limit in the titanium-base alloy. The precursor compounds are chemically reduced to produce an alloy material, without melting the alloy material. The alloy material may be consolidated.

Abstract: Shell molds and processes for making the shell molds that exhibit high emissivity in the red and infrared regions. In this manner, thermal resistance within a gap formed between solidifying cast metal and the interior mold surface is decreased. In one embodiment, the facecoat region is formed from a slurry composition comprising an aluminum oxide, a green chromium oxide and a silicon dioxide. In another embodiment, the facecoat region is formed from a slurry composition including zirconium silicate and silica with stucco layer of alumina is included.