Abstract: A method of forming cooling holes in a gas turbine engine component. The method includes the steps of forming a hole in the component extending between a first surface of the component and a second surface of the component opposite the first surface and supplying pressurized air to the hole from the second surface of the component. The method also includes the step of sensing a parameter representative of air flow through the hole. Further, the method includes enlarging the hole until the sensed parameter represents a preselected air flow rate through the hole.

Abstract: A method of applying thermal barrier coating systems to a metal piece having a cooling hole extending along a central axis through the piece from a first surface of the piece to a second surface of the piece opposite the first surface. The method includes spraying a bond coat on the first surface of the piece and spraying a thermal barrier coating on the bond coat. Further, the method includes spraying a high pressure fluid jet from a nozzle toward the hole and in a direction generally parallel to the central axis of the hole. The fluid jet is substantially free of solid particulate thereby permitting the jet to remove the bond coat and the thermal barrier coating from the hole without removing metal from the piece.

Abstract: A method for quality assurance of a laser shock peening process uses interferometry to form a fringe image from first and second interferograms of unstressed and stressed laser shock peened patches respectively of a workpiece. The fringe image may then be compared to a predetermined correlation of fringe images for indicating quality assurance. Stressing the laser shock peened patch may include loading the production and test workpieces during the production of the first and second images by interferometry while the production and test workpieces are fixtured. The loading may be done by heating, twisting, or bending of at least a portion of the production and test workpieces. The comparing of the production images of fringes may include comparing fringe characteristics of the laser shock peened patches on the production workpieces laser against fringe characteristics of the predetermined correlation.

Abstract: A fluid cooled article having a protective coating on a surface, for example an air cooled gas turbine engine article having a Thermal Barrier Coating, includes through an article wall a fluid cooling passage, and typically a plurality of passages, having openings sized to maintain desired fluid flow, unobstructed by coating within the passage at an exit opening. The passage has a first or inlet opening, which establishes the amount of fluid flow through the passage, and a second opening through which the flow exits the passage through a wall surface on which the coating is deposited.

Abstract: A fluid cooled article having a protective coating on a surface, for example an air cooled gas turbine engine article having a Thermal Barrier Coating, includes through an article wall a fluid cooling passage, and typically a plurality of passages, having openings sized to maintain desired fluid flow, unobstructed by coating within the passage at an exit opening. The passage has a first or inlet opening, which establishes the amount of fluid flow through the passage, and a second opening through which the flow exits the passage through a wall surface on which the coating is deposited.

Abstract: An apparatus for smoothing and densifying or increasing the density of a coating on a workpiece includes a laser for generating a laser beam and a cylindrical lens for focusing the laser beam into a line of light on the coating surface. A manipulator is provided for moving one of the workpiece or the laser and the light line generated thereby relative to one another to cause the light line to scan across the coating to remove any rough portions and provide a smoother surface with a higher density depending upon the nature of the coating material. In one embodiment of the present invention, a mechanism is provided to oscillate the laser light line to homogenize adverse effects caused by any hot spots along the line.

Abstract: A laser plasma spray apparatus for depositing a feed material onto a substrate includes a nozzle having a plasma confinement chamber into which a laser beam is focused, the focal point being at a distance sufficiently far from the substrate that the substrate is not melted. Finely divided feed material in a carrier gas flow is fed axially into the confinement chamber along the direction of the laser beam and melted in the plasma formed in the interaction of the laser beam, the feed material, and the gas at the focal point. The melted feed material is then directed to deposit onto the substrate, while the plasma energy is largely confined within the apparatus by the confinement chamber and a constriction in the flow path upstream of the confinement chamber.

Abstract: A component is fabricated by depositing a succession of overlying beads of a material, the pattern and position of the beads being assigned the proper characteristics of the corresponding section of the desired component. Shape definition is accomplished by characterizing the component as a series of sections or slices having the thickness of the bead, and programming a computer-controlled deposition head to deposit a succession of beads with the respective patterns and positions. Deposition is preferably by precision laser welding. Complex shapes having properties comparable to properties of forged or cast material are readily prepared. The material used in successive beads may be varied, producing a component of graded composition to achieve particular properties in various regions.

Abstract: A feed material is melted by a focussed laser beam in a partially confined interaction volume, and ejected from the interaction volume in a direction different from the axis of the laser beam. The feed material, preferably in the form of a finely divided powder fluidized by a gas stream, is fed to the interaction volume in a direction transverse to the axis of the laser beam. Confinement of the molten feed material is preferably attained using balanced gas pressures that do not permit the molten feed material to flow in the direction parallel to the laser beam. The energy density of the laser beam is preferably sufficiently high to form a plasma within the interaction volume from gas and vaporized feed material atoms, so that the feed material is introduced into the plasma.