Abstract: A method for forming a ceramic matrix composite (CMC) component for gas turbine engines. The method contemplates replacing a plurality of plies with insert material. The insert material can be partially cured or pre-cured and applied in place of a plurality of small plies or it may be inserted into cavities of a component in the form of a paste or a ply. The insert material is isotropic, being formed of a combination of matrix material and chopped fibers, tow, cut plies or combinations thereof. The use of the insert material allows for features such as thin edges (650) with thicknesses of less than about 0.030 inches and small radii such as found in corners (680, 710). The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: A containment case comprises a composite core, with an inner surface, and at least one ceramic layer integrated with the composite core. The at least one ceramic layer is bonded to the inner surface of the composite core with a resin. In another embodiment, a containment case comprises a composite core, with an inner surface, and a hybrid material comprising at least one ceramic material and at least one non-ceramic material. The hybrid material is disposed on the inner surface of the composite core. The hybrid material is bonded to the inner surface of the composite core with a resin. A method of fabricating a containment case includes the steps of disposing one or more layers of ceramic fabric on an inner surface of a composite core, infusing the composite core and the one or more layers of ceramic fabric with resin, and curing the resin.

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: A method for forming a polyimide composite article utilizes a polyimide resin system including at least a first prepolymer component and a second prepolymer component. A preform structure is tackified with the first prepolymer component. Using resin infusion or resin transfer molding techniques, the tackified preform structure is contacted with the second prepolymer component. The polyimide resin system is cured under suitable cure conditions so that the first and second prepolymer components mix and react to produce the polyimide composite structure.

Abstract: A method for fabricating a reinforced matrix composite comprising the step of providing a composite preform having a fibrous structure and applying matrix material onto the preform in locations along the preform. A barrier material is applied to at least a portion of the coated preform to direct the flow of matrix material into the preform. The composite preform is heated to a temperature sufficient to render the matrix material viscous and insufficient to cure the matrix material. The pressure to the interior of the composite preform is reduced, while the pressure to the barrier material is increased. The temperature is maintained to flow the matrix material into the composite preform and to force gases from the fibrous structure. The composite preform is then cured and cooled to form a reinforced matrix composite having a low void content and a substantially uniform matrix distribution.

Abstract: Methods for forming thermal oxidative barrier coatings for organic matrix composites include applying a bond coat having nano-particles dispersed in a polyimide matrix to a hot side surface of a component and overlying the bond coat with a thermal barrier layer comprising a silsesquioxane or an inorganic polymer. The nano-particles may include clay platelets, graphite flakes or a polyhedral oligomeric silsesquioxane. The bond coat may be applied as a liquid. The thermal barrier layer may be applied as a liquid, film, prepreg, molding compound, or a spray.

Abstract: A thermal oxidative barrier coating for organic matrix composites includes a bond coat having nano-particles dispersed in a polyimide matrix and a thermal barrier layer comprising a silsesquioxane or an inorganic polymer. The nano-particles may include clay platelets, graphite flakes or a polyhedral oligomeric silsesquioxane. The coated article may be utilized in gas turbine engine applications, particularly for a flow path duct adapted for exposure to high temperature, oxygen-containing environments.

Abstract: A tailorable polyimide resin system may be used to form an organic matrix composite (OMC) structure for use in high temperature applications. A thermal oxidative barrier coating on the OMC may include a bond coat comprising a tailorable polyimide resin system. The bond coat may include nano-particles such as clay platelets, graphite flakes or a polyhedral oligomeric silsesquioxane. The coating system may include a thermal barrier layer including a silsesquioxane or an inorganic polymer. The tailorable polyimide resin system includes first and second independent prepolymer components able to impart desired properties in the prepolymer blend or the crosslinked polyimide matrix.

Abstract: Method includes forming a preform utilizing a polyimide resin-impregnated fiber-reinforced layers; removing solvent from the system at initial vacuum, pressure, and temperature conditions for an initial time interval sufficient to remove substantially all the solvent; imidizing the polyimide resin system under second vacuum, pressure, and temperature conditions for a second time interval sufficient to substantially completely imidize the polyimide resin; consolidating the preform following imidization under third vacuum, pressure, and temperature conditions and including applying pressure to the preform when the preform is at a predetermined temperature; and solidifying the preform under fourth vacuum, pressure, and temperature conditions to provide a cured laminate structure having a shape of a turbine engine component.

Abstract: A process for forming a molded polymer resin fiber tube clamp, as well as the tube clamp formed by that process. Continuous top and bottom plies provide increased resistance to delamination/cracking as they sandwich a filler material. The tube clamp is free from exposed fiber ends so than no wear is produced on a tube being clamped.

Abstract: A ceramic matrix composite (CMC) component for gas turbine engines, the component having fine features such as thin edges with thicknesses of less than about 0.030 inches and small radii of less that about 0.030 inches formed using the combination of prepreg plies layed up with non-ply ceramic inserts. The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: A ceramic matrix composite (CMC) component for gas turbine engines, the component having fine features such as thin edges with thicknesses of less than about 0.030 inches and small radii of less that about 0.030 inches formed using the combination of prepreg plies layed up with non-ply ceramic inserts. The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: A containment case comprises a composite core, with an inner surface, and at least one ceramic layer integrated with the composite core. The at least one ceramic layer is bonded to the inner surface of the composite core with a resin. In another embodiment, a containment case comprises a composite core, with an inner surface, and a hybrid material comprising at least one ceramic material and at least one non-ceramic material. The hybrid material is disposed on the inner surface of the composite core. The hybrid material is bonded to the inner surface of the composite core with a resin. A method of fabricating a containment case includes the steps of disposing one or more layers of ceramic fabric on an inner surface of a composite core, infusing the composite core and the one or more layers of ceramic fabric with resin, and curing the resin.

Abstract: A method for forming a ceramic matrix composite (CMC) component for gas turbine engines. The method contemplates replacing a plurality of plies with insert material. The insert material can be partially cured or pre-cured and applied in place of a plurality of small plies or it may be inserted into cavities of a component in the form of a paste or a ply. The insert material is isotropic, being formed of a combination of matrix material and chopped fibers, tow, cut plies or combinations thereof. The use of the insert material allows for features such as thin edges with thicknesses of less than about 0.030 inches and small radii such as found in corners. The CMC components of the present invention replace small ply inserts cut to size to fit into areas of contour change or thickness change, and replace the small ply inserts with a fabricated single piece discontinuously reinforced composite insert, resulting in fewer defects, such as wrinkles, and better dimensional control.

Abstract: Tagged barrier coatings including an environmental barrier coating, a thermal barrier coating, or a combination thereof, and from about 0.01 mol % to about 30 mol % of a taggant.

Abstract: Methods for making barrier coatings including a taggant involving providing a barrier coating, and adding from about 0.01 mol % to about 30 mol % of a taggant to the barrier coating wherein the taggant comprises a rare earth element selected from lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, ytterbium, and lutetium, salts thereof, silicates thereof, oxides thereof, zirconates thereof, hafnates thereof, titanates thereof, tantalates thereof, cerates thereof, aluminates thereof, aluminosilicates thereof, phophates thereof, niobates thereof, borates thereof, and combinations thereof.

Abstract: Methods allowing for improved inspection of components having a barrier coating involving providing a component, and applying a barrier coating having at least one layer to the component where the layer of the barrier coating comprises a taggant.

Abstract: A method for fabricating a reinforced matrix composite comprising the step of providing a composite preform having a fibrous structure and applying matrix material onto the preform in locations along the preform. A barrier material is applied to at least a portion of the coated preform to direct the flow of matrix material into the preform. The composite preform is heated to a temperature sufficient to render the matrix material viscous and insufficient to cure the matrix material. The pressure to the interior of the composite preform is reduced, while the pressure to the barrier material is increased. The temperature is maintained to flow the matrix material into the composite preform and to force gases from the fibrous structure. The composite preform is then cured and cooled to form a reinforced matrix composite having a low void content and a substantially uniform matrix distribution.

Abstract: A reinforced matrix composite containment duct for gas turbine engines comprising a reinforced matrix composite containment duct having high strength integral flanges and pre-stressed reinforcing fibers, the reinforced matrix composite having uniform distribution of matrix material; and the reinforced matrix composite having less than or equal to 2.5% void space.

Abstract: A tailorable polyimide resin system may be used to form an organic matrix composite (OMC) structure for use in high temperature applications. A thermal oxidative barrier coating on the OMC may include a bond coat comprising a tailorable polyimide resin system. The bond coat may include nano-particles such as clay platelets, graphite flakes or a polyhedral oligomeric silsesquioxane. The coating system may include a thermal barrier layer including a silsesquioxane or an inorganic polymer. The tailorable polyimide resin system includes first and second independent prepolymer components able to impart desired properties in the prepolymer blend or the crosslinked polyimide matrix.