Abstract: A system and method for reconfiguring a turbine vane. In at least one embodiment, the system may be used to straighten an airfoil of a turbine vane segment to remove lean, twist, or racking, or any combination thereof. The airfoil may be straightened by fixing portions of the forward and aft hooks of the inner and outer shrouds of the turbine vane, restricting other portions of the forward and aft hooks of the inner and outer shrouds of the turbine vane to only move rotationally about a centerline of the inner or outer shrouds, and applying a load to various portions of the inner and outer shrouds and the airfoil to return the turbine vane to be within predetermined specifications.

Abstract: A process is provided for cleaning a surface of an internal cavity of a gas turbine component having sulfidation or sulfur bearing deposits comprising: inserting into the internal cavity a fluoride salt; and heating the fluoride salt and the component in an inert atmosphere for a time and at a temperature to clean the sulfidation or sulfur bearing deposits on the surface. In a preferred embodiment the cleaned internal surface is then coated with a metallic coating.

Abstract: This invention provides a thermal barrier ceramic coating for application to a metallic article, with the ceramic coating having a formula of NdxZr1-xOy with Z dissolved in, where 0<x<0.5 and 1.75<y<2 and wherein Z is an oxide of a metal selected from the group consisting of Y, Mg, Ca, Hf and mixtures thereof. In one embodiment Nd is added at a level up to 7 mole %. In another embodiment Z is yttrium and is added at a level of at least 6 wt %.

Abstract: A process is provided for crack-free welding a nickel based single crystal superalloy article containing at least 5 weight % total of Al and Ti. The process comprises: melting an article surface to be welded and a filler alloy with an energy source, preferably a laser, wherein the filler alloy is a composition of a nickel based single crystal superalloy except that the total of Al and Ti is reduced below 5 wt %; allowing the melted article surface and filler alloy to solidify to form a bead of deposit; providing a plurality of beads of adjacent deposits covering the article surface to be welded; and remelting the adjacent beads of deposits with the energy source to provide vertically oriented crystal growth in the deposits.

Abstract: This invention provides a thermal barrier ceramic coating for application to a metallic article, with the ceramic coating having a formula of RexZr1−xOy wherein Re is a rare earth element selected from the group consisting of Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb and Lu where O<X<0.5 and 1.75<Y<2. A preferred embodiment is wherein Re is Nd.

Abstract: This invention provides a metallic article with a metallic substrate having a thermal barrier ceramic coating on its surface, the ceramic coating comprising a plurality of first layers of about 6 to 8 wt % yttria stabilized zirconia alternating with a plurality of second layers of about 18 to 22 wt % yttria stabilized zirconia. The alternating layers can be distinct layers or gradient layers.

Abstract: A method is provided for drilling a hole through a metallic workpiece having a thermal barrier coating with a ceramic top coat by laser drilling a counterbore to a depth which extends through the ceramic top coat but not substantially into the metallic workpiece and then laser drilling the hole through the workpiece aligned with the counterbore, the counterbore having a diameter larger than the hole.

Abstract: A gas turbine engine abradeable seal system is provided comprising a seal assembly and a cooperating interacting turbine blade. The turbine blade has a tip portion containing cubic boron nitride abrasive particles and the seal assembly has a superalloy substrate with a bond coat thereon having a surface roughness of at least 300 RA and a porous ceramic abradeable seal material on the bond coat having a porosity of from 5 to 15 volume %.

Abstract: A blade tip cap of a turbine blade is repaired by restoring the tip rail and attaching a strengthening rib across the blade tip cap connecting the concave wall to the convex wall of the tip rail.

Abstract: The present invention provides a method of laser machining a cooling hole in a hollow gas turbine component, the cooling hole including a circular cross section metering hole and a diffuser with an opening which extends from a shape locus in the metering hole to a trapezoidal cross section opening by firing a series of laser pulses at an acute angle at the outer surface of the component toward the shape locus to create the diffuser opening, with the laser pulses penetrating the component outer surface up to but not substantially beyond the shape locus, then firing the laser through the shape locus and the inner surface of the component to create the metering hole having a circular cross section. Alternatively, the initial laser pulses are fired to create the central portion of the diffuser opening, then firing the laser to create the metering hole, followed by firing the laser along the peripheral portion of the diffuser opening.

Abstract: A process is provided for laser drilling to remove coating material obstructing cooling holes of a gas turbine component by utilizing a CNC component program which is preprogrammed with the general location of the cooling holes of a component to move a machine vision system and component relative to each other to each cooling hole location for a series of cooling holes, determining the actual location for each cooling hole and storing in the memory of the CNC or a data storage device the actual locations for the cooling holes for the series of cooling holes, followed by laser drilling based on the actual location of the cooling holes stored in the memory of the CNC or the data storage device to remove the coating material obstructing the cooling holes for the series of cooling holes. This process can be advantageously carried out to determine the actual location of the cooling holes either on a coated component or a component that has been prepared for coating.

Abstract: A maskant is provided for use during laser welding or drilling comprising a paste of metallic powder and silica.

Abstract: A method for repairing a turbine blade (10) wherein the tip (16) of the blade is removed (41,43) and a replacement cap is attached by welding (49). The cap may consist of a plate (48) attached by welding and a squealer (54) formed by depositing weld material (52), as illustrated in FIG. 3. The plate and/or squealer may be formed from a material different from the material of the airfoil portion (42) of the blade in order to optimize the performance of the blade.

Abstract: A process is provided for welding a nickel or cobalt based superalloy article to minimize cracking by preheating the entire weld area to a maximum ductility temperature range, maintaining such temperature during welding and solidification of the weld, raising the temperature for stress relief of the superalloy, then cooling at a rate effective to minimize gamma prime precipitation.

Abstract: A casting apparatus, comprising: a heating chamber having an open lower end defined by a periphery; a chill plate having a peripheral region for supporting one or more casting molds thereon and being in movable to move the molds from within the heating chamber to below the lower end of the heating chamber to withdraw the casting molds from the heating chamber; a cooling spool disposed at the periphery of the open lower end of the heating chamber and including a surface area for receiving heat energy radiated from at least one of the heating chamber and the casting molds; and a spool shield disposed at the cooling spool and movable to control an amount of the surface area of the cooling spool available for receiving the heat energy. In another embodiment there is an additional inner cooling spool movable inside the area surrounded by the casting molds for receiving radiant energy. A second spool shield at the inner spool controls its available surface area.

Abstract: A casting apparatus includes a substantially stationary heating chamber having an upper pouring opening and a substantially open lower end; an outer cooling spool disposed at a periphery of the open lower end of the heating chamber; a chill plate having an aperture therethrough and movable through the lower end of the heating chamber; a mold assembly receivable in the chamber and movable through the lower end of the chamber and including peripherally disposed mold cavities defining a substantially interior space accessible through the open lower end of the chamber, an inner cooling spool movable through the aperture of the chill plate and the open lower end of the mold assembly; a first actuator for vertically displacing the chill plate and mold assembly; and a second actuator for vertically displacing the inner cooling spool.

Abstract: An abradable seal is provided utilizing a laser to cut a pattern into the surface effective to improve abradability in the area of the pattern.

Abstract: A process is provided for producing an abrasive coating on a substrate surface by applying a bond coat by low pressure plasma spraying and anchoring to the bond coat abrasive particles by electroplating and embedding the particles into an oxidation resistant matrix by entrapment plating.

Abstract: A method for refurbishing turbine engine vanes in which the airfoils are removed and replaced. The original configuration of the vanes can be modified from a single casting or welded pair to a multi-piece component assembly comprising individual airfoil segments attached to the inner and outer platforms. The component assembly allows replacement of airfoils and/or platforms with improved castings in the form of improved alloys, improved physical geometry, or both. Modifications can be made in the vane class area without the need to modify the airfoil contour by brazing or other contour alteration processes. According to the method, the platforms are separated from the airfoils, the openings in the platforms are sealed, new airfoil sockets are cut into the platforms, and the vane is reassembled.

Abstract: A process is provided to strip a metallic coating from a turbine blade comprising attaching the blade to a positive lead from a power supply, submersing a portion of the blade with a metallic coating to be stripped into a bath of acidic electro stripping solution, said bath containing a negative lead from a power supply attached to a conductive grid; and providing a current to the blade in the bath for a period of time effective to remove the coating on the portion of the blade.