Abstract: Methods for creating a cast component, along with the resulting cast components, are provided. The method may provide for a controlled grain structure in the resulting cast component. The methods may include heating at least a first portion mold under controlled conditions, such as when the first portion of the mold is buried in a ceramic powder.

Abstract: Cast components are provided that include a first section comprising a first metal material and having first grains with a first average grain size and a second section comprising a second metal material and having second grains with a second average grain size.

Abstract: Methods for creating a cast component, along with the resulting cast components, are provided. The method may include heating a mold having a cavity therein; supplying a first molten metal material into the cavity of the mold such that the first molten metal material is directed to a first portion of the cavity of the mold; supplying a second molten metal material into the cavity of the mold such that the second molten metal material is directed to a second portion of the cavity of the mold, wherein the first molten metal material is compositionally different than the second molten metal material; and thereafter, allowing the first molten metal material and the second molten metal material to form the cast component.

Abstract: Methods for creating a cast component, along with the resulting cast components, are provided. The method may provide for a controlled grain structure in the resulting cast component. The methods may include heating at least a first portion mold under controlled conditions, such as when the first portion of the mold is buried in a ceramic powder.

Abstract: Methods for creating a cast component, along with the resulting cast components, are provided. The method may include heating a mold having a cavity therein; supplying a first molten metal material into the cavity of the mold such that the first molten metal material is directed to a first portion of the cavity of the mold; supplying a second molten metal material into the cavity of the mold such that the second molten metal material is directed to a second portion of the cavity of the mold, wherein the first molten metal material is compositionally different than the second molten metal material; and thereafter, allowing the first molten metal material and the second molten metal material to form the cast component.

Abstract: A nickel-based superalloy composition includes from about 5 to about 7 wt % aluminum, from about 4 to about 8 wt % tantalum, from about 3 to about 8 wt % chromium, from about 3 to about 7 wt % tungsten, from 1 to about 5 wt % molybdenum, from 1.5 to about 5 wt % rhenium, from 5 to about 14 wt % cobalt, from about 0 to about 1 wt % hafnium, from about 0.01 to about 0.03 wt % carbon, from about 0.002 to about 0.006 wt % boron, and balance nickel and incidental impurities. The composition may exhibit a sustained peak low cycle fatigue life at 1800° F./45 ksi of at least about 4000 cycles. The nickel-based superalloy composition may be used in single-crystal or directionally solidified superalloy articles, such as a blade, nozzle, a shroud, a splash plate, and a combustor of a gas turbine engine.

Abstract: A method for surface roughening a metal work piece includes disposing a region of the workpiece to be roughened proximate to a counter electrode. The region of the workpiece to be roughened and the counter electrode are subsequently disposed together in an electrolyte. An electric potential with current flow is applied between the work piece and the counter electrode to roughen the metal surface to a desired roughness.

Abstract: A nickel-based superalloy composition includes from about 5 to about 7 wt % aluminum, from about 4 to about 8 wt % tantalum, from about 3 to about 8 wt % chromium, from about 3 to about 7 wt % tungsten, from 1 to about 5 wt % molybdenum, from 1.5 to about 5 wt % rhenium, from 5 to about 14 wt % cobalt, from about 0 to about 1 wt % hafnium, from about 0.01 to about 0.03 wt % carbon, from about 0.002 to about 0.006 wt % boron, and balance nickel and incidental impurities. The composition may exhibit a sustained peak low cycle fatigue life at 1800° F./45 ksi of at least about 4000 cycles. The nickel-based superalloy composition may be used in single-crystal or directionally solidified superalloy articles, such as a blade, nozzle, a shroud, a splash plate, and a combustor of a gas turbine engine.

Abstract: A nickel-based superalloy composition includes from about 5 to about 7 wt % aluminum, from about 4 to about 8 wt % tantalum, from about 3 to about 8 wt % chromium, from about 3 to about 7 wt % tungsten, from 1 to about 5 wt % molybdenum, from 1.5 to about 5 wt % rhenium, from 5 to about 14 wt % cobalt, from about 0 to about 1 wt % hafnium, from about 0.01 to about 0.03 wt % carbon, from about 0.002 to about 0.006 wt % boron, and balance nickel and incidental impurities. The composition may exhibit a sustained peak low cycle fatigue life at 1800° F./45 ksi of at least about 4000 cycles. The nickel-based superalloy composition may be used in single-crystal or directionally solidified superalloy articles, such as a blade, nozzle, a shroud, a splash plate, and a combustor of a gas turbine engine.

Abstract: A nickel-based superalloy composition includes from about 5 to about 7 wt % aluminum, from about 4 to about 8 wt % tantalum, from about 3 to about 8 wt % chromium, from about 3 to about 7 wt % tungsten, from 1 to about 5 wt % molybdenum, from 1.5 to about 5 wt % rhenium, from 5 to about 14 wt % cobalt, from about 0 to about 1 wt % hafnium, from about 0.01 to about 0.03 wt % carbon, from about 0.002 to about 0.006 wt % boron, and balance nickel and incidental impurities. The composition may exhibit a sustained peak low cycle fatigue life at 1800° F./45 ksi of at least about 4000 cycles. The nickel-based superalloy composition may be used in single-crystal or directionally solidified superalloy articles, such as a blade, nozzle, a shroud, a splash plate, and a combustor of a gas turbine engine.

Abstract: A metallic sheath for a mounting on a component is disclosed. The metallic sheath comprises a nose portion extending in a chordwise direction, a first side-wall extending in the chordwise direction from the nose portion and a second side-wall extending in the chordwise direction from the nose portion wherein the second side-wall is bonded to the nose portion such that the nose portion, the first side-wall and the second side-wall form a cavity capable of receiving a portion of the component.

Abstract: A method of reducing crack propagation in an airfoil includes: providing an airfoil having a root spaced apart from a tip, spaced-apart leading and trailing edges, a suction side extending from the leading edge to the trailing edge, and an opposed pressure side extending from the leading edge and the trailing edge, supporting the airfoil against bending loads; and burnishing the airfoil using a burnishing element, so as to create at least one burnished section of residual compressive stress, the at least one burnished section being located adjacent the leading edge and spaced from the leading edge by an offset distance selected so as to avoid deformation of the leading edge.

Abstract: A method for surface roughening a metal work piece includes disposing a region of the workpiece to be roughened proximate to a counter electrode. The region of the workpiece to be roughened and the counter electrode are subsequently disposed together in an electrolyte. An electric potential with current flow is applied between the work piece and the counter electrode to roughen the metal surface to a desired roughness.

Abstract: A method of recovering rhenium from rhenium-containing superalloy scrap is provided. The superalloy is usually a nickel-based superalloy. The method includes the steps of forming an oxidation feedstock of flaky morphology of the superalloy scrap, and oxidizing the oxidation feedstock to convert rhenium into a volatile rhenium oxide. The flaky morphology of the oxidation feedstock is achieved by increasing the surface area of the superalloy scrap.

Abstract: An apparatus and method for hybrid machining a workpiece is disclosed. The workpiece is powered as an anode, a cutter is powered as a cathode and a cutting fluid or coolant is circulated therebetween. The cutter is made of a conductive material and a non-conductive abrasive material. The hybrid machine performs a roughing pass machining operation in which material is removed from the workpiece at a relatively high rate using a high-speed electro-erosion (HSEE) process. Then, the hybrid machine performs a finish pass machining operation in which material is removed from the workpiece using precision electro-grinding (PEG) process at a different differential electrical potential and/or flushing rate than the roughing pass machining operation to provide a smooth finish without thermal effects on the workpiece.

Abstract: A method of recovering rhenium from rhenium-containing superalloy scrap is provided. The superalloy is usually a nickel-based superalloy. The method includes the steps of forming an oxidation feedstock of flaky morphology of the superalloy scrap, and oxidizing the oxidation feedstock to convert rhenium into a volatile rhenium oxide. The flaky morphology of the oxidation feedstock is achieved by increasing the surface area of the superalloy scrap.

Abstract: A thermal barrier coating and deposition process for a component intended for use in a hostile thermal environment, such as the turbine, combustor and augmentor components of a gas turbine engine. The TBC has a first coating portion on at least a first surface portion of the component. The first coating portion is formed of a ceramic material to have at least an inner region, at least an outer region overlying the inner region, and a columnar microstructure whereby the inner and outer regions comprise columns of the ceramic material. The columns of the inner region are more closely spaced than the columns of the outer region so that the inner region of the first coating portion is denser than the outer region of the first coating portion, wherein the higher density of the inner region promotes the impact resistance of the first coating portion.

Abstract: A superalloy composition comprising, in weight percent: about 6.2-6.6 Al, about 6.5-7.0 Ta, about 6.0-7.0 Cr, about 6.25-7.0 W, about 1.5-2.5 Mo, about 0.15-0.60 Hf, 0.0-1.0 Re, 6.5-9.0 Co, optionally, 0.03-0.06 C, optionally, up to about 0.004 B, optionally up to about 0.03 total of one or more rare earth elements selected from yttrium (Y), lanthanum (La), or cerium (Ce), balance nickel, such that the superalloy composition exhibits a stress rupture capability improvement of at least 15% over a base stress rupture capability of a base composition nominally comprising, in weight percent: 6.5 Al, 6.6 Ta, 6.0 Cr, 6.25 W, 1.5 Mo, 0.15 Hf, 0.0 Re, 7.5 Co. Articles incorporating the superalloy composition include a gas turbine engine component such as a high pressure turbine nozzle or nozzle segment.

Abstract: A method for repairing a nickel-base superalloy article, such as a gas turbine stationary flowpath shroud having flowpath cooling holes therein that has previously been in service, includes the steps of providing the nickel-base superalloy article that has previously been in service; and applying a restoration to a surface of the article. The restoration is applied by the steps of providing a restoration nickel-base alloy, wherein the restoration nickel-base alloy preferably has no more than about 15 weight percent chromium and no more than about 0.01 percent yttrium, thereafter applying a restoration coating of the restoration nickel-base alloy to the surface of the article by a hyper-velocity oxyfuel metal spray process or a low-pressure plasma spray process, and thereafter heating the article with the restoration coating applied to the surface thereof to a sufficiently high temperature to diffusion bond the restoration coating to the surface of the article. The article is then returned to service.

Abstract: A method for repairing a nickel-base superalloy article, such as a gas turbine stationary flowpath shroud having flowpath cooling holes therein that has previously been in service, includes the steps of providing the nickel-base superalloy article that has previously been in service; and applying a restoration to a surface of the article. The restoration is applied by the steps of providing a restoration nickel-base alloy, wherein the restoration nickel-base alloy preferably has no more than about 15 weight percent chromium and no more than about 0.01 percent yttrium, thereafter applying a restoration coating of the restoration nickel-base alloy to the surface of the article by a hyper-velocity oxyfuel metal spray process or a low-pressure plasma spray process, and thereafter heating the article with the restoration coating applied to the surface thereof to a sufficiently high temperature to diffusion bond the restoration coating to the surface of the article. The article is then returned to service.