Patent application number | Description | Published |
20100071812 | UNIDIRECTIONALLY-SOLIDIFICATION PROCESS AND CASTINGS FORMED THEREBY - A process capable of producing large metallic castings having lengths of one hundred centimeters or more and a unidirectional crystal structure substantially free of freckle defects. The process includes pouring a molten metal alloy into a preheated mold within a heating zone, withdrawing the mold from the heating zone, through a heat shield, and into a cooling zone to directionally solidify the molten metal alloy, and then cooling the mold to produce the casting and the unidirectional crystal structure thereof. The heat shield operates as a barrier to thermal radiation between the heating zone and the cooling zone, and the mold is withdrawn at a rate that, in combination with the heat shield, maintains a thermal gradient to solidify the molten metal alloy and form primary dendrite arms having an average spacing therebetween of about 150 to about 500 micrometers. | 03-25-2010 |
20100147481 | METHODS OF MANUFACTURING CASTED ARTICLES, AND SYSTEMS - A method for manufacturing a casted article is presented. The method includes steps of forming a casted article by a liquid metal cooled directional solidification process, removing a metallic material from a surface of the casted article and inspecting the surface of the casted article. The surface of the casted article is inspected for the presence of the metallic material by exposing the surface to a visualization reagent. A system for manufacturing the casted article is also presented. | 06-17-2010 |
20130022803 | UNIDIRECTIONALLY-SOLIDIFICATION PROCESS AND CASTINGS FORMED THEREBY - A process capable of producing large metallic castings having lengths of one hundred centimeters or more and a unidirectional crystal structure substantially free of freckle defects. The process includes preheating a mold within a heating zone of a directional casting apparatus, pouring a molten metal alloy into a cavity of the mold, and then withdrawing the mold from the heating zone, through a heat shield, and into a cooling zone of the directional casting apparatus to directionally solidify the molten metal alloy within the cavity. The heating and cooling zones establish an axial thermal gradient that defines a solidification front in the molten metal alloy within the cavity. The mold is withdrawn at a withdrawal rate that, in combination with the axial thermal gradient, causes the solidification front to be substantially flat and perpendicular to the withdrawal direction. | 01-24-2013 |
Patent application number | Description | Published |
20100170654 | Casting Molds for Use in Directional Solidification Processes and Methods of Making - 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. | 07-08-2010 |
20120152483 | UNIDIRECTIONAL SOLIDIFICATION PROCESS AND APPARATUS AND SINGLE-CRYSTAL SEED THEREFOR - A single-crystal seed, apparatus and process for producing a casting having a single-crystal (SX) microstructure. The seed has a geometry that includes a vertex capable of destabilizing an oxide film that forms at the interface between the seed and a molten metal during the casting process, and thereby promotes a continuous single-crystal grain growth and reduces grain misorientation defects that can initiate from the seed/metal interface. | 06-21-2012 |
20120312426 | Alumina-Forming Cobalt-Nickel Base Alloy and Method of Making an Article Therefrom - 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. | 12-13-2012 |
20120312434 | COBALT-NICKEL BASE ALLOY AND METHOD OF MAKING AN ARTICLE THEREFROM - 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. | 12-13-2012 |
20130160967 | CASTING METHODS FOR MAKING ARTICLES HAVING A FINE EQUIAXED GRAIN STRUCTURE - 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. | 06-27-2013 |
20130206352 | UNIDIRECTIONAL SOLIDIFICATION PROCESS AND APPARATUS AND SINGLE-CRYSTAL SEED THEREFOR - A single-crystal seed, apparatus and process for producing a casting having a single-crystal (SX) microstructure. The seed has a geometry that includes a vertex capable of destabilizing an oxide film that forms at the interface between the seed and a molten metal during the casting process, and thereby promotes a continuous single-crystal grain growth and reduces grain misorientation defects that can initiate from the seed/metal interface. | 08-15-2013 |
Patent application number | Description | Published |
20080257517 | MOLD ASSEMBLY FOR USE IN A LIQUID METAL COOLED DIRECTIONAL SOLIDIFICATION FURNACE - A mold assembly for a liquid metal cooled directional solidification furnace having a cooling chamber provided with liquid metal and a heating chamber includes a mold member having a main body portion that defines an interior mold cavity. The mold member is adapted to be positioned in the heating chamber. The mold assembly also includes a chill-plate formed from a material having a thermal diffusivity a 600° K greater than approximately 10 E-6 m2/s, inert to at least one of molten tin and molten aluminum and adapted to be at least partially immersed in the liquid metal. The chill-plate includes a main body portion having a first surface extending to a second surface through an intermediate portion. The chill-plate is adapted to establish a thermal gradient between the mold member and the heating chamber. | 10-23-2008 |
20090126893 | Liquid Metal Directional Casting Process - Processes for directionally casting liquid metal to form an articles can include compressing a seal intermediate a mold chill plate and a mold assembly, wherein the seal circumscribes a shell mold in the mold assembly; filling the shell mold in the mold assembly with molten metal; immersing the mold assembly into a liquid metal cooling bath from a bottom portion to a top portion of the mold assembly; and transmitting heat from the mold assembly to the liquid metal cooling bath to solidify the molten metal from the bottom portion to the top portion of the mold assembly. | 05-21-2009 |
20090126894 | LIQUID METAL DIRECTIONAL CASTING APPARATUS - An apparatus for directionally casting articles generally includes a seal between a mold assembly and chill plate. In one embodiment, the mold assembly includes a skirt laterally extending from at least one shell mold, wherein the skirt includes a channel disposed in a bottom surface that is configured to surround the at least one shell mold. A chill plate fastened to a bottom of the mold assembly and includes a boss having a shape complementary to the channel, wherein the boss of the chill plate is seated within the channel of the mold assembly to define the seal about the at least one shell mold. | 05-21-2009 |
20090205799 | CASTING MOLDS FOR USE IN A DIRECTIONAL SOLIDIFICATION PROCESS AND METHODS OF MAKING | 08-20-2009 |
20090314390 | Alloy Castings Having Protective Layers and Methods of Making the Same - An alloy casting having a protective layer disposed on a surface of the casting is provided. The protective layer is resistant to liquid metal attack, and wherein the protective layer includes an oxide of an element present in the alloy. A method of forming a protective layer on a surface of the alloy casting is also provided. The method includes disposing the alloy in a mold, and oxidizing an element of the alloy to form a protective layer on the surface of the casting. | 12-24-2009 |