Abstract: Tailorable polyimide resin systems suitable for processing by resin transfer molding (RTM) and resin infusion (RI) methods. An exemplary resin system includes first and second prepolymer components present in respective amounts to provide the desired processibility. The cured polyimide system exhibits high glass transition temperature and other properties required for gas turbine engine applications. The first and second prepolymer components independently comprise a monomeric mixture or a reaction product of a diamine component, a dianhydride component, and an end group component.

Abstract: Including a disk, a plurality of circumferentially spaced apart airfoils extending radially outwardly from the disk, a plurality of shroud segments being disposed circumferentially between the plurality of airfoils and configured to attach to a corresponding airfoil of the plurality of airfoils and a plurality of wear surfaces, where at least one wear surface of the plurality of wear surfaces is configured and disposed to prevent excessive wear between the adjacent shroud segments. Each shroud segment of the plurality of shroud segments may be attached to a corresponding airfoil by weld connections to permit clearance during translation friction welding of the airfoil to the disk hub are located to avoid high stress areas.

Abstract: Ultrasonic inspection system, method, and apparatus for subsurface ultrasonic inspection of curved objects. The inspection system includes an apparatus having a support structure for supporting a selected transducer and a selected acoustic mirror adapted for immersion in a coupling fluid. The total inspection path distance for the ultrasonic radiation includes a first portion defined by the transducer-to-mirror distance, and a second portion including the mirror-to-object distance. The first and second portions may be relatively adjusted within a constant total inspection path distance to focus the ultrasonic radiation at a desired subsurface depth. Selection of the transducer is at least partly dependent on subsurface depth of the desired inspection zone. Selection of the acoustic mirror is at least partly dependent on the selected transducer, the total inspection path distance, and curvature of the inspection object.

Abstract: A method for forming a ceramic layer on the surface of a turbine component. This method comprises the following steps: (a) providing a turbine component having a surface; (b) providing at least one ceramic tape overlaying the component surface; and (c) manually pressing the at least one ceramic tape against the component surface at a temperature of from about 150° to about 700° F. (from about 66° to about 371° C.) so as to cause the at least one ceramic tape to adhere to the component surface.

Abstract: According to an embodiment of the invention, an article of manufacture for use in a gas turbine engine is disclosed. The article comprises a part having a surface covered with a ceramic thermal barrier coating. The thermal barrier coating has an outer surface covered with a sacrificial phosphate coating, wherein the sacrificial phosphate coating reacts with contaminant compositions to prevent contaminant infiltration into the thermal barrier coating.

Abstract: Apparatus including an exhaust nozzle assembly having a translatable structure operable to open and close a flow diverting port in an exhaust duct. The translatable structure includes a forward region partly defining a converging nozzle region. The translatable structure includes a rearward region partly defining a diverging nozzle region. The forward region and the rearward region join at an inner edge that partly defines a throat constriction. The translatable structure is translatable between a plurality of operational positions each associated with a longitudinal position of the throat constriction. In a first operational position, the flow diverting port is fully closed. In a second operational position, the flow diverting port is fully opened. In a first intermediate operational position, the flow diverting port is fully closed. In a second intermediate operational position, the flow diverting port is at least partly opened.

Abstract: A composition comprising a liquid mixture having: a corrosion resistant metal particulate component comprising aluminum-containing metal particulates, wherein the aluminum-containing metal particulates have a phosphate and/or silica-containing insulating layer; a glass-forming binder component; and a liquid carrier component. Also disclosed is a method comprising the following steps: (a) providing an article comprising a metal substrate; (b) imparting to the metal substrate an electrical charge; and (c) electrostatically applying a liquid coating composition to the electrically charged metal substrate, wherein the liquid coating composition comprises a liquid mixture having: a corrosion resistant metal particulate component comprising aluminum-containing metal particulates having a phosphate and/or silica-containing insulating layer; glass-forming binder component; and a liquid carrier component.

Abstract: A method for locally heat-treating a gas turbine engine superalloy article to improve resistance to strain-induced fatigue of the article is disclosed. The method comprises providing a gas turbine engine superalloy article having a gamma prime solvus temperature; and locally over aging only a selected portion of the article to locally improve fatigue resistance at the selected portion of the article, wherein the local over age cycle includes heating at about 843° C. for about 3 to 4 hours.

Abstract: A composition comprising a corrosion resistant metal particulate component comprising aluminum-containing metal particulates, wherein the aluminum-containing metal particulates have a phosphate and/or silica-containing insulating layer; and a glass-forming binder component. Also disclosed is a method comprising the following steps: (a) providing an article comprising a metal substrate; (b) imparting to the metal substrate an electrical charge; and (c) electrostatically depositing a coating composition on the electrically charged metal substrate, wherein the coating composition comprises aluminum-containing metal particulates having a phosphate and/or silica-containing insulating layer; and glass-forming binder component.

Abstract: In accordance with an embodiment of the invention, an article is provided. The article comprises a substrate comprised of silicon containing material, an environmental barrier coating (EBC) overlying the substrate and a thermal barrier coating (TBC) on the environmental barrier coating. The thermal barrier coating comprising a compound having a rhombohedral phase.

Abstract: An enclosure for apparatus that, during operation, generates heat and/or sound energy comprises at least one wall defining at least a portion of the enclosure hollow interior. The wall comprises in sequence outwardly from the enclosure hollow interior an inner panel, an outer panel, a support frame between the inner and outer panels to hold the inner and outer panels spaced apart, and a vibrator isolator between the support frame and the panels. Panels or panel segments of the wall primarily are made of non-metallic composites to provide a structurally strong, lightweight enclosure that includes enhanced acoustic characteristics and reduced heat transfer through enclosure walls, along with fire protection and in-plane shear loading capabilities.

Abstract: A brazing material including about 20 to about 60 percent by weight silver, about 1 to about 4 percent by weight aluminum, about 20 to about 65 percent by weight copper, about 3 to about 18 percent by weight titanium and about 1 to about 4 percent by weight nickel.

Abstract: An article comprising a silicon-containing substrate, a silicide-containing bond coat layer overlying the substrate, and typically an environmental barrier coating overlaying the bond coat layer. An article is also provided wherein the environmental barrier coating comprises: (1) an optional inner silica scale layer overlaying the bond coat layer; (2) intermediate layer overlaying the inner silica scale layer, or the bond coat layer in the absence of the inner silica scale layer, and comprising mullite, or a combination of mullite with a barium strontium aluminosilicate, a yttrium silicate, or a calcium aluminosilicate; and (3) an outer steam-resistant barrier layer overlaying the intermediate layer and consisting essentially of an alkaline earth silicate/aluminosilicate. Processes are also provided for forming the silicide-containing bond coat layer over the substrate, followed by forming the environmental barrier coating over the bond coat layer.

Abstract: A brazing material including about 20 to about 60 percent by weight gold, about 6 to about 16 percent by weight nickel, about 16 to about 60 percent by weight copper and about 6 to about 16 percent by weight titanium.

Abstract: Method comprising providing a signal tube extending generally from an engine component disposed on a hot side of a firewall in a gas turbine engine to at least one engine control mechanism disposed on a cool side of the firewall. A fuse in the signal tube is operable responsive to a breach in the signal tube to change from a first condition to a second condition to prevent an over-temperature situation on the cool side of the firewall. The engine control mechanism operates the engine according to a first operating logic utilizing a pressure signal related to a static pressure of a fluid in the signal tube. Loss of the pressure signal causes the engine control mechanism to change to a second operating logic which does not utilize the pressure signal.

Abstract: An article comprising a silicon-containing substrate, a silicide-containing bond coat layer overlying the substrate, and an environmental barrier coating (EBC) overlying the bond coat layer, wherein the EBC comprises a corrosion resistant outer layer comprising a corrosion resistant metal silicate. A process is also provided for forming the corrosion resistant outer layer over the silicide-containing bond coat layer.

Abstract: Zirconia-containing ceramic compositions that are capable of providing thermal barrier coatings wherein the zirconia is stabilized in the cubic crystalline phase. These compositions comprise at least about 50 mole % zirconia and a stabilizing amount up to about 49 mole % of a stabilizer component comprising: (1) a first metal oxide selected from the group consisting of ytterbia, neodymia, mixtures of ytterbia and neodymia, mixtures of ytterbia and lanthana, mixtures of neodymia and lanthana, and mixtures of ytterbia, neodymia and lanthana in an amount of from about 5 to about 49 mole % of the composition; and (2) a second metal oxide selected from the group consisting of yttria, calcia, ceria, scandia, magnesia, india and mixtures thereof in an amount of about 4 mole % or less of the composition. The ceramic composition further comprises one or more of a third metal oxide selected from the group consisting of: (a) hafnia in an amount from about 0.

Abstract: A brazing material including about 40 to about 60 percent by weight gold, about 5 to about 16 percent by weight nickel and about 35 to about 55 percent by weight copper.

Abstract: A brazing material including about 2 to about 30 percent by weight gold, about 4 to about 14 percent by weight nickel, about 25 to about 65 percent by weight copper, about 1 to about 3 percent by weight aluminum and about 20 to about 55 percent by weight silver.

Abstract: A reduced thermal conductivity thermal barrier coating having improved impact resistance for an underlying substrate of articles that operate at, or are exposed to, high temperatures. This coating comprises an inner high fracture toughness layer nearest to the underlying substrate and having a thickness up to about 5 mils (127 microns) sufficient to impart impact resistance to the thermal barrier coating, and comprises a zirconia-containing ceramic composition having a c/a ratio of the zirconia lattice in the range of from about 1.011 to about 1.016 and stabilized in the tetragonal phase by a stabilizing amount of a stabilizing metal oxide selected from the group consisting of yttria, calcia, ceria, scandia, magnesia, india, lanthana, gadolinia, neodymia, samaria, dysprosia, erbia, ytterbia, europia, praseodymia, and mixtures thereof.