Patents by Inventor William D. Cowie

William D. Cowie has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6551064
    Abstract: An intermetallic article such as a gas turbine engine component and method of manufacture thereof includes a region having compressive residual stresses imparted by laser shock peening (LSP) extending into the article from a laser shock peened surface. One embodiment includes a turbine or compressor blade with an intermetallic airfoil having a leading edge and at least one laser shock peened surface extending radially along at least a portion of the leading edge with a region having compressive residual stresses imparted by laser shock peening (LSP) extending into the intermetallic airfoil from the laser shock peened surface.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: April 22, 2003
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie
  • Patent number: 6541733
    Abstract: A method for laser shock peening rotor blade leading and trailing edges of gas turbine engine integrally bladed rotors and disks that are not blocked by other rows of blades. The method includes continuously firing a stationary laser beam, which repeatable pulses between relatively constant periods, along at least a portion of leading or trailing edges of the blade, with the laser beam aimed at an oblique angle with respect to a surface of the edge such that laser pulses form overlapping elliptical shaped laser spots. In the exemplary embodiment of the invention, the elliptical shaped laser spots have an overlap of about 50% and are on the order of 11.7 mm by 4 mm in diameter. Another method is for laser shock peening rotor blade leading and trailing edges of gas turbine engine integrally bladed rotors and disks that are blocked by other rows of blades.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: April 1, 2003
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, Jeffrey H. Nussbaum, Abraham S. Assa, Andrea G. M. Cox, James R. Zisson, Albert E. McDaniel, William D. Cowie
  • Patent number: 6341936
    Abstract: The present invention is a method for operating a gas turbine engine airfoil having leading and trailing edges subject to FOD (foreign object damage) damage. The method includes inspecting the airfoil along at least a first one of the edges having at least a first laser shock peened patch along the first one of the edges, ascertaining FOD lengths of foreign object damage (FOD) extending from the first one of the edges into the airfoil within the patch, and allowing the airfoil to remain in service without repair if the FOD lengths are up to a maximum length of about one-half of a width of the laser shock peened patch, as measured from the edge.
    Type: Grant
    Filed: April 21, 2000
    Date of Patent: January 29, 2002
    Assignee: General Electric Company
    Inventors: William D. Cowie, Seetharamaiah Mannava, Jeffrey H. Nussbaum
  • Patent number: 6183882
    Abstract: A test coupon is formed from a metallic strip having opposite first and second sides that generally define a plane of the strip and the strip includes a laser shock peened patch of the strip that has first and second laser shock peened surfaces on the first and second sides, respectively, first and second laser shocked regions having deep compressive residual stresses imparted by the laser shock peening extending into the strip from the first and second laser shock peened surfaces, respectively, and a deflection of a portion of the strip from a position of the portion before the laser shock peening. The deflection is formed by the laser shock peening such that at least a part and preferably substantially all of the deflection lies in the plane and the test coupon preferably includes an indicating means to indicate the deflection.
    Type: Grant
    Filed: June 29, 1998
    Date of Patent: February 6, 2001
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie, P. Kennard Wright, III, Robert D. McClain
  • Patent number: 6155789
    Abstract: A gas turbine engine airfoil assembly for damping airfoil vibrations includes a metallic airfoil having an outer surface and a chordwise extending cavity beneath the outer surface of the airfoil. A damper is trapped within the cavity and a region in the airfoil surrounding the cavity has compressive residual stresses imparted by laser shock peening. The damper is preferably a chordwise extending linear wire having a distal end tacked down within the cavity. The invention includes a method for constructing the assembly for damping airfoil vibrations.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: December 5, 2000
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie, Robert L. Yeaton
  • Patent number: 5951790
    Abstract: A method for quality assurance of a laser process and more particularly a laser shock peening process that uses a test coupon having a deflection formed by a laser firing. The test coupon is from a metallic strip having opposite first and second sides that generally define a plane of the strip and the strip includes a laser shock peened patch of the strip that has first and second laser shock peened surfaces on the first and second sides, respectively, first and second laser shocked regions having deep compressive residual stresses imparted by the laser shock peening extending into the strip from the first and second laser shock peened surfaces, respectively, and a deflection of a portion of the strip from a position of the portion before the laser shock peening. The deflection is formed by the laser shock peening such that at least a part and preferably substantially all of the deflection lies in the plane of the strip and the test coupon preferably includes an indicating means to indicate the deflection.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: September 14, 1999
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie, P. Kennard Wright, III, Robert D. McClain
  • Patent number: 5846057
    Abstract: A crack weld repair and method, particularly, for a gas turbine engine blade or other metallic component in the engine, providing a metallic substrate, a metallic filler bonded onto a substrate bond surface on the metallic substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate beneath the substrate bond surface. One embodiment provides a laser shock peened surface below the weld material filled void in a damaged area of the component forming a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the component. Optionally, the surface over the repaired area of the weld filled void may also be laser shock peened forming a second region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the weld repair.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: December 8, 1998
    Assignee: General Electric Company
    Inventors: Stephen J. Ferrigno, William D. Cowie, Seetharamaiah Mannava
  • Patent number: 5846054
    Abstract: A dovetail assembly for mounting blades with dovetail roots axially into disk dovetail slots around a disk periphery which is subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating. The dovetail assembly has stress risers each in the form of a transition fillet between a neck or an area of minimum width and a pressure face which is designed to be a contact surface between complementary blade dovetail roots and disk dovetail slots formed between adjacent disk posts. The region around the stress riser has deep compressive residual stresses imparted by laser shock peening and is radially adjacent the stress riser and extends inward from a laser shocked surface of the component along the transition fillet.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: December 8, 1998
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie, Herbert Halila
  • Patent number: 5742028
    Abstract: A method of laser shock peening a gas turbine engine article by loading the article such that a portion of the article to be laser shock peened is placed in a loaded condition while the portion is laser shock peened using a laser to fire a laser beam with sufficient power to vaporize material on a laser shock peening surface of the portion of the article to form a region in the portion having deep compressive residual stresses imparted by the laser shock peening process extending into the article from the laser shock peened surface. The loaded condition may be either in compression or preferably tension.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: April 21, 1998
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie
  • Patent number: 5735044
    Abstract: A crack weld repair and method, particularly, for a gas turbine engine blade or other metallic component in the engine, providing a metallic substrate, a metallic filler bonded onto a substrate bond surface on the metallic substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate beneath the substrate bond surface. One embodiment provides a laser shock peened surface below the weld material filled void in a damaged area of the component forming a region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the component. Optionally, the surface over the repaired area of the weld filled void may also be laser shock peened forming a second region of deep compressive residual stresses imparted by laser shock peening (LSP) extending from the laser shock peened surface into the weld repair.
    Type: Grant
    Filed: December 12, 1995
    Date of Patent: April 7, 1998
    Assignee: General Electric Company
    Inventors: Stephen J. Ferrigno, William D. Cowie, Seetharamaiah Mannava
  • Patent number: 5620307
    Abstract: Gas turbine engine blade with a metallic airfoil having a radially outer tip extending chordwise between a leading edge and a trailing edge and at least one laser shock peened surface extending radially along at least a portion of the tip and a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: April 15, 1997
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie, Herbert Halila, James E. Rhoda, Stephen J. Ferrigno
  • Patent number: 5591009
    Abstract: Gas turbine engine fan blade with a metallic airfoil having a leading edge, a trailing edge, and a radially outer tip, and at least one laser shock peened surface located along the leading edge with a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the airfoil from the laser shock peened surface.
    Type: Grant
    Filed: January 17, 1995
    Date of Patent: January 7, 1997
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie, Herbert Halila, James E. Rhoda, James E. Gutknecht
  • Patent number: 5584586
    Abstract: A bearing element having a metallic body with a bearing contact curved surface portion, at least one laser shock peened surface encompassing at least a portion of the contact surface portion, and a region having deep compressive residual stresses imparted by laser shock peening (LSP) extending into the body from the laser shock peened surface. The present invention may be used for rolling elements such as ball bearing elements or elongated roller elements and for static elements such as races which may be singular or split and may have circumferentially spaced oil feed passages radially disposed therethrough.
    Type: Grant
    Filed: March 4, 1996
    Date of Patent: December 17, 1996
    Assignee: General Electric Company
    Inventors: Dominick A. Casarcia, William D. Cowie, Seetharamaiah Mannava
  • Patent number: 5569018
    Abstract: Gas turbine engine static component with a metallic panel section, either linear or curved, that is susceptible to cracks initiated by features on the component has an elongated laser shock peened region having deep compressive residual stresses imparted by laser shock peening (LSP) disposed between the feature and a portion of the panel section, which is to be protected from failure, such that the laser shock peened region diverts cracks that propagate from the feature away from the portion of the panel section. The laser shock peened region preferably extends through the component and is may be formed by simultaneously laser shock peening first and second laser shock peened surface areas to form the laser shock peened region.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: October 29, 1996
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie
  • Patent number: 5525429
    Abstract: A metallic article and method for producing such an article, having a metallic substrate, at least one metallic layer sprayed onto a laser shock peened surface area of the substrate, and a region having deep compressive residual stresses imparted by laser shock peening extending into the substrate from the laser shock peened surface. The metallic substrate and or layer may be made from an alloy such as a Cobalt or a Nickel based superalloy. The substrate may be made from Nickel Base forgings or Titanium base forgings. An exemplary embodiment of the present invention is a gas turbine engine rotor component such a disk and, more particularly, a turbine disk suitable for use in a hot section of a gas turbine engine. The invention may be used for new or refurbished parts to restore dimensions of the component and, in particular, radial dimensions.
    Type: Grant
    Filed: March 6, 1995
    Date of Patent: June 11, 1996
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie, Stephen J. Ferrigno
  • Patent number: 5522706
    Abstract: Turbomachinery rotor component, which may be a disk or drum rotor, having an annular rim disposed about a centerline for securing the blades to the rotor and that is subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating. An annular channel slot is cut around the rim, has outer annular overhanging rails, and has at least one stress riser in the form of a three sided slot cut in the radial direction through one of the rails. A region around rounded corners of the stress riser has deep compressive residual stresses imparted by laser shock peening and extends inward from a laser shocked surface of the component encompassed by the region.
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: June 4, 1996
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, William D. Cowie
  • Patent number: 5492447
    Abstract: Turbomachinery rotor components having a metallic body with at least a portion of the body subject to a tensile stress field due to centrifugal and thermal growth induced forces generated by the rotor when the rotor is rotating, at least one stress riser in the stress field portion that causes stress concentration when the rotor is rotating, and at least one region of the component around the stress riser having deep compressive residual stresses imparted by laser shock peening (LSP).
    Type: Grant
    Filed: October 6, 1994
    Date of Patent: February 20, 1996
    Assignee: General Electric Company
    Inventors: Seetharamaiah Mannava, Albert E. McDaniel, William D. Cowie