Abstract: A multi-grain selector device includes an outer body having exterior surfaces. The outer body includes a cooling side configured to face a cooling plate of a casting furnace and an opposite mold side configured to face into a mold. The outer body includes an array of multiple grain selector columns each formed from two or more transversely oriented, elongated channels that are fluidly coupled with each other in an end-to-end arrangement oriented along a growth direction that extends from the cooling side of the outer body toward the mold side of the outer body. The selector columns extend to growth openings on the mold side of the outer body. Each of the selector columns is configured to form a single grain column out of the corresponding growth opening that is part of a columnar grained article to be formed in the mold that grows along the growth direction.

Abstract: A method of manufacturing a three-dimensional target object may include forming a shell from loose machining powder using an additive manufacturing process and subjecting the shell to a densification process to form a target object. The shell may define an enclosure that contains additional machining powder. The densification process may include causing metallurgical bonding between the shell and additional machining powder contained in the enclosure defined by the shell and shrinking and/or distorting the shape of the shell to conform the target object to a three-dimensional model for the target object. The shell may include a plurality of layers and/or parts that differ at least in respect of density. The plurality of layers and/or parts may be configured based at least in part on the shrinking and/or distorting to the shape of the shell needed to conform the target object to the three-dimensional model for the target object.

Abstract: A multi-grain selector device includes an outer body having exterior surfaces. The outer body includes a cooling side configured to face a cooling plate of a casting furnace and an opposite mold side configured to face into a mold. The outer body includes an array of multiple grain selector columns each formed from two or more transversely oriented, elongated channels that are fluidly coupled with each other in an end-to-end arrangement oriented along a growth direction that extends from the cooling side of the outer body toward the mold side of the outer body. The selector columns extend to growth openings on the mold side of the outer body. Each of the selector columns is configured to form a single grain column out of the corresponding growth opening that is part of a columnar grained article to be formed in the mold that grows along the growth direction.

Abstract: A method of manufacturing a three-dimensional target object may include forming a shell from loose machining powder using an additive manufacturing process and subjecting the shell to a densification process to form a target object. The shell may define an enclosure that contains additional machining powder. The densification process may include causing metallurgical bonding between the shell and additional machining powder contained in the enclosure defined by the shell and shrinking and/or distorting the shape of the shell to conform the target object to a three-dimensional model for the target object. The shell may include a plurality of layers and/or parts that differ at least in respect of density. The plurality of layers and/or parts may be configured based at least in part on the shrinking and/or distorting to the shape of the shell needed to conform the target object to the three-dimensional model for the target object.

Abstract: A method for manufacturing a three-dimensional part. The method includes: performing partial densification processing on loose machining powder, to form a densified and sealed enclosure, where there is still loose machining powder accommodated inside the enclosure; and performing overall densification processing on the enclosure and the machining powder inside the enclosure, so as to implement metallurgical bonding between the machining powder inside the enclosure and the enclosure during the densification, thereby forming a target three-dimensional part.

Abstract: An emitter for a cathode of an X-ray tube is provided that includes a shaped emitting surface. The emitting surface is shaped in a suitable process in order to enable the emitting surface to focus electron beams emitted from the emitting surface on a focal spot on a target of less than 1.0 mm without the need for any additional focusing elements in the X-ray tube.

Abstract: Articles suitable for use in high temperature applications, such as turbomachinery components, and methods for making such articles, are provided. One embodiment is an article. The article comprises a material comprising a plurality of L12-structured gamma-prime phase precipitates distributed within a matrix phase at a concentration of at least 20% by volume, wherein the gamma-prime phase precipitates are less than 1 micrometer in size, and a plurality of A3-structured eta phase precipitates distributed within the matrix phase at a concentration in the range from about 1% to about 25% by volume. The solvus temperature of the eta phase is higher than the solvus temperature of the gamma-prime phase. Moreover, the material has a median grain size less than 10 micrometers.

Abstract: A method of making a nanocomposite permanent magnet is provided. The method comprises applying an extreme shear deformation to hard magnetic phase nanoparticles and soft magnetic phase nanoparticles to align at least a portion of the hard phase magnetic particles and to produce a nanocomposite permanent magnet.

Abstract: Method for joining wires using low resistivity joints is provided. More specifically, methods of joining one or more wires having superconductive filaments, such as magnesium diboride filaments, are provided. The wires are joined by a low resistivity joint to form wires of a desired length for applications, such in medical imaging applications.

Abstract: An emitter for a cathode of an X-ray tube is provided that includes a shaped emitting surface. The emitting surface is shaped in a suitable process in order to enable the emitting surface to focus electron beams emitted from the emitting surface on a focal spot on a target of less than 1.0 mm without the need for any additional focusing elements in the X-ray tube.

Abstract: Methods for joining dissimilar high-temperature alloys are provided, along with articles, such as turbine airfoils, formed by the method. The method comprises interposing a barrier material between a first segment and a second segment to form a segment assembly. The first segment comprises a titanium aluminide material, and the second segment comprises a nickel alloy. The barrier material comprises a primary constituent element present in the barrier material at a concentration of at least about 30 weight percent of the barrier material, and the primary constituent element is a transition metal element of Group 1B, Group 4B (excluding titanium and zirconium), Group 5B, Group 6B, Group 7B, or Group 8B (excluding nickel).

Abstract: A method for manufacturing a three-dimensional part. The method includes: performing partial densification processing on loose machining powder, to form a densified and sealed enclosure, where there is still loose machining powder accommodated inside the enclosure; and performing overall densification processing on the enclosure and the machining powder inside the enclosure, so as to implement metallurgical bonding between the machining powder inside the enclosure and the enclosure during the densification, thereby forming a target three-dimensional part.

Abstract: A steel composition resistant to sulfidic corrosion has been discovered. The newly discovered steel composition comprises the elements Fe, C, Si, Cu, and Mn wherein the composition comprises from about 96.80 to about 99.00 percent by weight iron, from about 0.10 to about 0.30 percent by weight carbon, from about 0.20 to about 1.40 percent by weight silicon, from about 0.50 to about 1.50 percent by weight copper, and from about 0.20 to about 1.00 percent by weight manganese, wherein the composition is substantially free of chromium, and wherein the composition contains less than 0.1 percent by weight nickel, molybdenum, or tungsten.

Abstract: Articles suitable for use in high temperature applications, such as turbomachinery components, and methods for making such articles, are provided. One embodiment is an article. The article comprises a material comprising a plurality of L12-structured gamma-prime phase precipitates distributed within a matrix phase at a concentration of at least 20% by volume, wherein the gamma-prime phase precipitates are less than 1 micrometer in size, and a plurality of A3-structured eta phase precipitates distributed within the matrix phase at a concentration in the range from about 1% to about 25% by volume. The solvus temperature of the eta phase is higher than the solvus temperature of the gamma-prime phase. Moreover, the material has a median grain size less than 10 micrometers.

Abstract: A method of making a nanocomposite permanent magnet is provided. The method comprises applying an extreme shear deformation to hard magnetic phase nanoparticles and soft magnetic phase nanoparticles to align at least a portion of the hard phase magnetic particles and to produce a nanocomposite permanent magnet.

Abstract: Articles that include a material that has L12-structured gamma-prime phase precipitates within a matrix phase at a concentration of at least 20% by volume are disclosed. The gamma-prime phase precipitates are less than 1 micrometer in size. The material also has A3-structured eta phase precipitates distributed within the matrix phase at a concentration in the range from about 1% to about 25% by volume. The articles may be formed by mechanically working a workpiece that has at least about 40% nickel, about 1.5% to about 8% titanium, and about 1.5% to about 4.5% aluminum. The workpiece may be worked at a temperature below a solvus temperature of the eta phase; and then heat treated at a temperature sufficient to dissolve any gamma prime phase present in the workpiece but below the solvus temperature of the eta phase.

Abstract: Method for joining wires using low resistivity joints is provided. More specifically, methods of joining one or more wires having superconductive filaments, such as magnesium diboride filaments, are provided. The wires are joined by a low resistivity joint to form wires of a desired length for applications, such in medical imaging applications.

Abstract: The present invention provides a method for forming a refractory metal-intermetallic composite. The method includes providing a first powder comprising a refractory metal suitable for forming a metal phase; providing a second powder comprising a silicide precursor suitable for forming an intermetallic phase; blending the first powder and the second powder to form a powder blend; consolidating and mechanically deforming the powder blend at a first temperature; and reacting the powder blend at a second temperature to form the metal phase and the intermetallic phase of the refractory metal-intermetallic composite, wherein the second temperature is higher than the first temperature.

Abstract: A method of manufacturing a magnetic resonance imaging (MRI) device is provided including providing at least one magnet positioned between a keeper device and a yoke, the keeper device being positioned at a pole region of the at least one magnet, positioning at least one pole device at the pole region of the at least one magnet, and removing the keeper device from the pole region to allow the at least one pole device to be positioned at the pole region of the at least one magnet.

Abstract: Articles suitable for use in high temperature applications, such as turbomachinery components, and methods for making such articles, are provided. One embodiment is an article. The article comprises a material comprising a plurality of L12-structured gamma-prime phase precipitates distributed within a matrix phase at a concentration of at least 20% by volume, wherein the gamma-prime phase precipitates are less than 1 micrometer in size, and a plurality of A3-structured eta phase precipitates distributed within the matrix phase at a concentration in the range from about 1% to about 25% by volume. The solvus temperature of the eta phase is higher than the solvus temperature of the gamma-prime phase. Moreover, the material has a median grain size less than 10 micrometers. The method comprises providing a workpiece, the workpiece comprising at least about 40% nickel, from about 1.5% to about 8% titanium, and from about 1.5% to about 4.5% aluminum.