Abstract: The present disclosure is directed to pre-cured composites for use in manufacturing rotor blade components of a wind turbine. In one embodiment, the pre-cured composites are pultruded composites having a continuous base portion with a plurality of integral protrusions extending from the continuous base portion, and a fabric layer cured with the continuous base portion. Further, adjacent protrusions are separated by a gap.

Abstract: A method of forming a component having an internal passage defined therein includes positioning a jacketed core with respect to a mold. The jacketed core includes a hollow structure formed from a first material, an inner core disposed within the hollow structure, and a core channel that extends from at least a first end of the inner core through at least a portion of inner core. The method also includes introducing a component material in a molten state into a cavity of the mold, such that the component material in the molten state at least partially absorbs the first material from the jacketed core within the cavity. The method further includes cooling the component material in the cavity to form the component. The inner core defines the internal passage within the component.

Abstract: A mold assembly for use in forming a component having an internal passage defined therein includes a mold defining a mold cavity therein, and a deoxygenated core positioned with respect to the mold. The deoxygenated core includes an inner wall that at least partially defines a sealed core chamber within the deoxygenated core. The sealed core chamber has a substantially reduced oxygen content, and a portion of the deoxygenated core is positioned within the mold cavity such that the inner wall of the portion of the deoxygenated core defines the internal passage when the component is formed in the mold assembly.

Abstract: A method of forming a component having an internal passage defined therein includes positioning a jacketed core with respect to a mold. The jacketed core includes a hollow structure formed from a first material, an inner core disposed within the hollow structure, and a core channel that extends from at least a first end of the inner core through at least a portion of inner core. The method also includes introducing a component material in a molten state into a cavity of the mold, such that the component material in the molten state at least partially absorbs the first material from the jacketed core within the cavity. The method further includes cooling the component material in the cavity to form the component. The inner core defines the internal passage within the component.

Abstract: The present disclosure is directed to pre-cured composites for use in manufacturing rotor blade components of a wind turbine. In one embodiment, the pre-cured composites are pultruded composites having a continuous base portion with a plurality of integral protrusions extending from the continuous base portion, and a fabric layer cured with the continuous base portion. Further, adjacent protrusions are separated by a gap.

Abstract: Various embodiments include an infusion bolt and methods of manufacturing such a bolt. In one embodiment an infusion bolt includes: a head having an axially accessible opening extending therethrough; and a shaft extending from the head, the shaft having: an inner cavity fluidly connected with the axially accessible opening of the head; a radially outer surface surrounding the inner cavity; and a set of axially extending apertures along the radially outer surface, the set of axially extending apertures fluidly connected with the inner cavity and the axially accessible opening in the head.

Abstract: Embodiments of the present disclosure relate generally to systems and methods for manufacturing an airfoil component. The system can include: a geometrical mold; an elongated flexible sleeve having a closed-off interior and positioned within the geometrical mold, wherein the elongated flexible sleeve is further positioned to have a desired geometry; an infusing channel in fluid communication with the closed-off interior of the elongated flexible sleeve and configured to communicate a resinous material thereto; a vacuum channel in fluid communication with the closed-off interior of the elongated flexible sleeve and configured to vacuum seal the closed-off interior of the elongated flexible sleeve; and a glass fiber layer positioned within the closed-off interior of the elongated flexible sleeve.

Abstract: Embodiments of the present disclosure relate generally to systems and methods for manufacturing an airfoil component. The system can include: a geometrical mold; an elongated flexible sleeve having a closed-off interior and positioned within the geometrical mold, wherein the elongated flexible sleeve is further positioned to have a desired geometry; an infusing channel in fluid communication with the closed-off interior of the elongated flexible sleeve and configured to communicate a resinous material thereto; a vacuum channel in fluid communication with the closed-off interior of the elongated flexible sleeve and configured to vacuum seal the closed-off interior of the elongated flexible sleeve; and a glass fiber layer positioned within the closed-off interior of the elongated flexible sleeve.

Abstract: Various embodiments include an infusion bolt and methods of manufacturing such a bolt. In one embodiment an infusion bolt includes: a head having an axially accessible opening extending therethrough; and a shaft extending from the head, the shaft having: an inner cavity fluidly connected with the axially accessible opening of the head; a radially outer surface surrounding the inner cavity; and a set of axially extending apertures along the radially outer surface, the set of axially extending apertures fluidly connected with the inner cavity and the axially accessible opening in the head.

Abstract: A method of making a laminate component and method of removing voids from a pre-preg ply and pre-preg component are provided. The method of making a laminate includes laying up a plurality of pre-preg plies in a desired geometry, the plurality of pre-preg plies having a plurality of fibers and a resin. The method includes creating at least one void-reducing channel in at least one ply of the plurality of pre-preg plies, the void-reducing channel being perpendicular to a fiber orientation in the at least one ply. The void reducing channel locally re-orients the fibers adjacent to the void-reducing channel in the at least one pre-preg ply. The method includes laminating the plurality of pre-preg plies. The resin fills the at least one void-reducing channel and the laminate component has a porosity margin of about 1.5%.

Abstract: A precipitation-hardened stainless steel alloy comprises, by weight: about 14.0 to about 16.0 percent chromium; about 6.0 to about 8.0 percent nickel; about 1.25 to about 1.75 percent copper; greater than about 1.5 to about 2.0 percent molybdenum; about 0.001 to about 0.025 percent carbon; niobium in an amount greater than about twenty times that of carbon; and the balance iron and incidental impurities. The alloy has an aged microstructure and an ultimate tensile strength of at least about 1100 MPa and a Charpy V-notch toughness of at least about 69 J. In one embodiment, the aged microstructure includes martensite and not more than about 10% reverted austenite. In another embodiment, the alloy includes substantially all martensite and substantially no reverted austenite. The alloy is useful for making turbine airfoils.

Abstract: A system for performing an in-situ polarization scan of a component surface includes a sensor connected to the component surface at a sensor connection, and the sensor generates a signal reflective of a current flow at the sensor connection. A power supply connected to the component surface at an electrical connection produces a voltage potential at the electrical connection. An electrolyte coats the sensor connection and the electrical connection. A method for performing an in-situ polarization scan of a component surface includes sensing a current flow on the component surface, generating a voltage potential on the component surface, and placing an electrolyte over at least a portion of the component surface.

Abstract: A system for reducing corrosion in a compressor includes a compressor blade having a corrosion potential. A sensor connected to the compressor blade generates a signal reflective of the corrosion potential. A power supply connected to the compressor blade at an electrical connection produces an electrical potential at the electrical connection. An electrolyte coats at least a portion of the sensor and the electrical connection. A method for reducing corrosion in a compressor includes sensing a corrosion potential of a compressor blade and generating a signal reflective of the corrosion potential. The method further includes generating an electrical potential at an electrical connection on the compressor blade and flowing an electrolyte over at least a portion of the compressor blade and the electrical connection.

Abstract: A system for performing an in-situ polarization scan of a component surface includes a sensor connected to the component surface at a sensor connection, and the sensor generates a signal reflective of a current flow at the sensor connection. A power supply connected to the component surface at an electrical connection produces a voltage potential at the electrical connection. An electrolyte coats the sensor connection and the electrical connection. A method for performing an in-situ polarization scan of a component surface includes sensing a current flow on the component surface, generating a voltage potential on the component surface, and placing an electrolyte over at least a portion of the component surface.

Abstract: A shaped rotor wheel, a turbo machine including the rotor wheel, and a method for producing the same are disclosed. In an embodiment, a rotor wheel is provided which includes at least one disk member and at least one spacer member, and is a capable of carrying and axially spacing one or more stages of blades. Also disclosed is a method for producing such a rotor wheel using metal powders as a starting material, and processing the metal powder using powder metallurgy techniques.

Abstract: A precipitation-hardened stainless steel alloy comprises, by weight: about 14.0 to about 16.0 percent chromium; about 6.0 to about 8.0 percent nickel; about 1.25 to about 1.75 percent copper; greater than about 1.5 to about 2.0 percent molybdenum; about 0.001 to about 0.025 percent carbon; niobium in an amount greater than about twenty times that of carbon; and the balance iron and incidental impurities. The alloy has an aged microstructure and an ultimate tensile strength of at least about 1100 MPa and a Charpy V-notch toughness of at least about 69 J. In one embodiment, the aged microstructure includes martensite and not more than about 10% reverted austenite. In another embodiment, the alloy includes substantially all martensite and substantially no reverted austenite. The alloy is useful for making turbine airfoils.

Abstract: A shaped rotor wheel, a turbo machine including the rotor wheel, and a method for producing the same are disclosed. In an embodiment, a rotor wheel is provided which includes at least one disk member and at least one spacer member, and is a capable of carrying and axially spacing one or more stages of blades. Also disclosed is a method for producing such a rotor wheel using metal powders as a starting material, and processing the metal powder using powder metallurgy techniques.

Abstract: A precipitation-hardened stainless steel alloy comprises, by weight: about 14.0 to about 16.0 percent chromium; about 6.0 to about 7.0 percent nickel; about 1.25 to about 1.75 percent copper; about 0.5 to about 2.0 percent molybdenum; about 0.025 to about 0.05 percent carbon; niobium in an amount greater than about twenty times to about twenty-five times that of carbon; and the balance iron and incidental impurities. The alloy has an aged microstructure and an ultimate tensile strength of at least about 1100 MPa and a Charpy V-notch toughness of at least about 69 J. The aged microstructure includes martensite and not more than about 10% reverted austenite and is useful for making turbine airfoils.

Abstract: A precipitation-hardened stainless steel alloy comprises, by weight: about 14.0 to about 16.0 percent chromium; about 6.0 to about 7.0 percent nickel; about 1.25 to about 1.75 percent copper; about 0.5 to about 2.0 percent molybdenum; about 0.025 to about 0.05 percent carbon; niobium in an amount greater than about twenty times to about twenty-five times that of carbon; and the balance iron and incidental impurities. The alloy has an aged microstructure and an ultimate tensile strength of at least about 1100 MPa and a Charpy V-notch toughness of at least about 69 J. The aged microstructure includes martensite and not more than about 10% reverted austenite and is useful for making turbine airfoils.

Abstract: A method for fabricating a turbine bucket and an apparatus facilitate reducing tip shroud creep. The method includes providing a turbine bucket that includes a tip shroud including at least one seal rail. The method also includes coupling at least one cutter tooth to the tip shroud, wherein the at least one cutter tooth is fabricated from an abradable material that enables the at least one cutter tooth to be removed from the tip shroud during operation of the turbine engine.