Abstract: A calibration standard for calibrating an eddy current inspection probe sized and shaped to inspect a preselected non-planar feature of a manufactured part. The feature extends in a longitudinal direction and in a lateral direction. Further, the feature has an end profile as viewed in the longitudinal direction having a substantially invariant shape and orientation. The calibration standard includes a body having a non-planar surface extending in a longitudinal direction and in a lateral direction. The standard also has an end profile as viewed in the longitudinal direction of the surface substantially identical to the profile of the feature. The surface of the body has an elongate narrow opening extending into the body substantially normal to the surface and traversing the surface of the body at a substantially constant angle with respect to the longitudinal direction of the surface as viewed normal to the surface.

Abstract: A cooling shroud segment for a high pressure turbine that provides improved cooling in the region of the side panels from the midsection thereof forward to the leading edge and particularly in the midsection of the side panel. A shroud subassembly can be formed from a pair of such adjacent shroud segments with opposed adjacent side panels where the spacing of the outlets of the cooling air passages exiting from each of these adjacent side panels are staggered and where the adjacent panels have a spline seal slot with a humped section in at least the midsection of the side panel above and across the outlets of the cooling air passages exiting from the midsection of the side panel, in combination with a spline seal positioned in the gap between the opposed adjacent side panels. This shroud subassembly provides more uniform impingement cooling coverage and localizes more of the cooling air exiting the outlets from these passages in the midsection of the opposed side panels.

Abstract: Apparatus for stripping ceramic coatings from the surfaces of articles. The apparatus includes a dedicated pressure vessel, such as an autoclave, which is maintained at an elevated temperature. Caustic solution is preheated to a first elevated temperature before injecting it into the autoclave, and the caustic solution is filtered and cooled after use in the autoclave. The articles are stripped of coating by maintaining the articles at an elevated temperature and pressure for a predetermined time. Various options include the use of analytical equipment to maintain the chemistry of the caustic solution and use of a volatile organic solution to prepressurize the autoclave and shorten cycle time. The autoclave is maintained in a nitrogen chamber to minimize the risks associated with volatile components.

Abstract: A turbine nozzle includes a plurality of airfoils and integral hubs brazed into corresponding seats of outer and inner bands. The hubs have brazeless fillets blending the bands to the airfoils.

Abstract: A blisk includes a disk having a rim from which extends a row of blades. The rim includes axially opposite overhangs one of which includes an arcuate balance land disposed eccentrically to the centerline axis of the disk for balancing the blisk.

Abstract: A method for controlled removal of a portion of a diffusion coating from the outer surface of a nickel-containing superalloy article. A diffusion coating typically includes a diffusion layer between an outer aluminide layer and the nickel-containing substrate. The method includes contacting the coated superalloy article in a preselected chemical stripping solution for a preselected period of time sufficient to remove only the outer aluminide layer, without substantially affecting the diffusion layer underlying the outer aluminide layer. After neutralizing the stripping solution, the article can be inspected and repaired as needed. The aluminide outer layer can then be restored in a conventional manner.

Abstract: An exhaust nozzle for an aircraft engine. The nozzle includes a mount for attaching the exhaust nozzle to a downstream end of the engine and first and second opposed upstream flaps moveably connected to the mount having inner surfaces defining an upstream exhaust gas flowpath. Each upstream flap extends between an upstream end and a downstream end and is moveable relative to the mount between an open position in which the downstream ends of the upstream flaps are spaced by a first distance, and a closed position in which the downstream ends touch to substantially block flow through the exhaust gas flowpath. First and second opposed downstream flaps are moveably connected to the first and second upstream flaps having inner surfaces defining a downstream exhaust gas flowpath.

Abstract: An augmenter includes an insert which reduces thermal stresses caused by hot combustion gases impinging the augmentor. The augmentor also includes a plurality of radial flameholder gutters and at least one outer circumferential flameholder connected to the radial flameholders to form a radial cap. The insert is contoured to conform to the radial cap and is attached to the radial cap. The insert shields the radial cap and includes a top surface, a bottom surface, and a plurality of openings extending therebetween. The openings permit the insert to be attached to the radial cap.

Abstract: A casing for a gas turbine engine having a longitudinal axis extending therethrough, including a first casing portion having a substantially arcuate section and a split-line flange extending from each end thereof and a second casing portion having a substantially arcuate section and a split-line flange extending from each end thereof. The first and second casing portions are mated at each end by connecting together respective pairs of the split-line flanges. A channel is formed in at least one mating surface of the split-line flanges to provide an axial passage therethrough so that air flow provided to the axial passage reduces a temperature gradient between the arcuate sections and the flanges of the first and second casing portions.

Abstract: A mechanical coupling to transfer torque between cooperating rotatable members each of substantially circular cross section and aligned along an axis of rotation comprises first and second members including, respectively, first and second surface portions in juxtaposition across an interface. Each surface portion includes a plurality of spaced apart teeth mechanically interlocking at the interface. The first surface portion comprises a fiber reinforced material including fibers oriented within about 45°, on either side, of an axis of rotation. Provided is a clamp to hold the first and second surface portions together at the interface.

Abstract: A thermal barrier coating (TBC) system for components designed for use in a hostile thermal environment, such as the turbine, combustor and augmentor sections of a gas turbine engine. The TBC system employs a thermal-insulating ceramic topcoat that is compatible with known metallic bond coats, such as diffusion aluminides and MCrAlY and NiAl coatings. The ceramic topcoat is formed of zirconia partially stabilized by about one up to less than six weight percent yttria and further stabilized by about one to about ten weight percent of magnesia and/or hafnia, to exhibit improved impact resistance.

Abstract: A process for manufacturing components of gas turbine engine combustors, including the steps of performing a plurality of forming steps on a workpiece of a designated material to produce a combustor component of desired size and shape without exceeding a forming limit of the designated material, the forming steps being performed without any intermediate heat treatment on the workpiece.

Abstract: A method of repairing an annular transpiration cooled liner for a combustion chamber of a gas turbine engine. An annular portion of the liner including a damaged region is removed from between an upstream section and a downstream section of the liner. Sheet metal is formed into an annular replacement section having at least one axial seam extending between an upstream end and a downstream end of the replacement section. The replacement section is sized and shaped similarly to the removed annular portion of the liner. The upstream end of the formed annular section is joined to the upstream section of the liner and the downstream end of the formed annular section is joined to the downstream section of the liner.

Abstract: A turbine nozzle includes outer and inner bands between which extend a plurality of vanes for channeling combustion gases. Each of the vanes includes leading and trailing edges, and pressure and suction sides extending therebetween, and also a bow along the trailing edge to increase pressure in the gases adjacent the inner band. The vanes also include a thermal barrier coating (TBC) selectively disposed solely along the suction side between the leading and trailing edges.

Abstract: A diffusion aluminide coating having a graded structure is applied over a nickel base superalloy substrate. The coating has an inner region of a diffusion aluminide adjacent to the substrate rich in a reactive element, typically Hf, Si or combinations of the two. The near surface region is a diffusion aluminide which is substantially free of reactive elements. Such coatings when used as bond coats in thermal barrier coating systems exhibit improved spallation performance.

Abstract: A stator vane frame assembly including an outer structure ring, an inner structure ring, a set of discrete vanes each connecting the outer structure ring and the inner structure ring forming an inner and outer platforms with neighboring vanes defining a set of flow paths, a set of sealing members contoured to a set of gaps between the set of vanes disposed to sealing the gap. A method for applying a sealing member to the gaps between a platform formed resulting from the coupling between vanes including affixing a set of stator vanes on an inner frame and an outer frame, and sealing a set of sealing members on the backside surface of a stator vane frame. The discrete nature of individual vane blade sealed by the sealing members renders the stator vane frame assembly to add a damping effect which increases the fatigue life of the vane, and permits the use of lower strength, lighter, and less expensive material.

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.

Abstract: A plurality of rotors are individually measured for determining relative eccentricity between forward and aft annular mounting ends thereof. The measured rotor eccentricities are stacked analytically to minimize eccentricity from a centerline axis. The rotors are then assembled axially end-to-end to correspond with the stacked measured eccentricities thereof.

Abstract: A method of depositing a ceramic thermal barrier coating on an article that will be subjected to a hostile environment, such as turbine, combustor and augmentor components of a gas turbine engine. The thermal barrier coating is deposited by electron beam physical vapor deposition (EBPVD) using process parameters that include an absolute pressure of greater than 0.010 mbar and an oxygen partial pressure of greater than 50%, preferably at or close to 100%. Under these conditions, the desired ceramic material is evaporated with an electron beam to produce a vapor that deposits on the component to form a thermal barrier coating of the ceramic material.

Abstract: A turbine blade includes an integral airfoil, platform, shank, and dovetail, with a pair of holes in tandem extending through the platform and shank in series flow communication with an airflow channel inside the shank. Cooling air discharged through the tandem holes effects multiple, convection, impingement, and film cooling using the same air.