Abstract: Slurry and tape compositions include particles of a precursor that converts to a ceramic material when heated to a firing temperature, at least one binder that is capable of adhering the particles of the ceramic precursor together to form a pliable prepreg tape, at least one liquid plasticizer, and at least one solvent in which the binder is dissolved. The solvent may be sufficiently volatile to evaporate from the slurry composition during formation of the tape, yet the tape may also be pliable as a result of the slurry composition containing a sufficient amount of the liquid plasticizer.

Abstract: Slurry and tape compositions include particles of a precursor that converts to a ceramic material when heated to a firing temperature, at least one binder that is capable of adhering the particles of the ceramic precursor together to form a pliable prepreg tape, at least one liquid plasticizer, and at least one solvent in which the binder is dissolved. The solvent may be sufficiently volatile to evaporate from the slurry composition during formation of the tape, yet the tape may also be pliable as a result of the slurry composition containing a sufficient amount of the liquid plasticizer.

Abstract: Methods for forming ceramic matrix composite (CMC) components are provided. In one exemplary embodiment, a method comprises automatically laying up CMC plies. Laying up plies includes transferring a CMC ply to a layup tool; applying heat to the CMC ply; and stacking the CMC ply with at least one other CMC ply. In various embodiments, CMC plies may be laid up using an automated machine. In some embodiments, a CMC ply may be transferred to a layup tool using an automated machine and the CMC ply may be stacked with at least one other CMC ply using the automated machine.

Abstract: Methods for forming ceramic matrix composite (CMC) components are provided. In one exemplary embodiment, a method comprises automatically laying up CMC plies. Laying up plies includes transferring a CMC ply to a layup tool; applying heat to the CMC ply; and stacking the CMC ply with at least one other CMC ply. In various embodiments, CMC plies may be laid up using an automated machine. In some embodiments, a CMC ply may be transferred to a layup tool using an automated machine and the CMC ply may be stacked with at least one other CMC ply using the automated machine.

Abstract: Slurry and tape compositions include particles of a precursor that converts to a ceramic material when heated to a firing temperature, at least one binder that is capable of adhering the particles of the ceramic precursor together to form a pliable prepreg tape, at least one liquid plasticizer, and at least one solvent in which the binder is dissolved. The solvent may be sufficiently volatile to evaporate from the slurry composition during formation of the tape, yet the tape may also be pliable as a result of the slurry composition containing a sufficient amount of the liquid plasticizer.

Abstract: Methods for repairing a turbine airfoil constructed from a CMC material are provided via filling a cavity located in the turbine airfoil with a ceramic paste (e.g., including a ceramic powder and a binder), heating the ceramic paste in the cavity to remove the binder, thereby forming a porous ceramic material, and adding a molten ceramic material to the porous ceramic material. The cavity can be defined in an airfoil of the turbine airfoil (e.g., on a tip or cap of the airfoil). Intermediates formed during the repair of a turbine airfoil are also provided. The intermediate can generally include an airfoil comprising a CMC material, a cavity defined in the airfoil, and a porous ceramic material filling the cavity.

Abstract: In certain embodiments of the present disclosure a method for modifying a composite article is described. The method includes positioning a plug made from composite material at a site on the composite article. The method further includes rotating at least one of the plug and the article at a rate of speed sufficient to form an inertia bond between the plug and the site of the composite article. The plug and the site are engaged to effect an inertia bond therebetween.

Abstract: Slurry and tape compositions and processes for producing CMC articles. The slurry composition contains particles of a precursor that converts to a ceramic material when heated to a firing temperature, at least one binder that is capable of adhering the particles of the ceramic precursor together to form a pliable prepreg tape, at least one liquid plasticizer, and a solvent in which the binder is dissolved.

Abstract: In certain embodiments of the present disclosure a method for modifying a composite article is described. The method includes positioning a plug made from composite material at a site on the composite article. The method further includes rotating at least one of the plug and the article at a rate of speed sufficient to form an inertia bond between the plug and the site of the composite article. The plug and the site are engaged to effect an inertia bond therebetween.

Abstract: Methods for repairing a turbine airfoil constructed from a CMC material are provided via filling a cavity located in the turbine airfoil with a ceramic paste (e.g., including a ceramic powder and a binder), heating the ceramic paste in the cavity to remove the binder, thereby forming a porous ceramic material, and adding a molten ceramic material to the porous ceramic material. The cavity can be defined in an airfoil of the turbine airfoil (e.g., on a tip or cap of the airfoil). Intermediates formed during the repair of a turbine airfoil are also provided. The intermediate can generally include an airfoil comprising a CMC material, a cavity defined in the airfoil, and a porous ceramic material filling the cavity.

Abstract: Aspects of the invention provide for an aperture reinforcement structure. In one embodiment, a composite laminate is disclosed, including: a first sheet of material having a first aperture therein; a second sheet of material having a second aperture therein corresponding to the first aperture; and a reinforcement structure having: a continuous fiber including a plurality of convolutions affixed to at least one of the first sheet of material or the second sheet of material, the plurality of convolutions surrounding at least one of the first aperture or the second aperture; and a resin binding the plurality of convolutions to one another.

Abstract: A method of manufacturing a carbon-based tooling for use as the support during melt infiltration processing of a prepreg preform used, for example, to manufacture turbine engine components, comprising forming an admixture of chopped carbon fibers, graphite powder and a high durometer thermosetting organic resin, applying a potion of the admixture at room temperature onto the surface of an aluminum die, initially curing the admixture as applied to the aluminum die for a period of 3-5 hours at a temperature of between about 100 and 200 degrees C., removing the carbon-based tooling from the aluminum die and carbonizing the tooling by heating the initially cured tooling to a temperature of about 750 degrees C for a period of about 40 hours.

Abstract: A method and apparatus for filling preforms with resin or slurry includes a tank for holding the slurry and an autoclave for holding the preforms. The tank and autoclave have a common vacuum system connected thereto, and the tank is disposed above the autoclave. This arrangement provides a compact casting system which utilizes a vacuum and gravity to transfer slurry from the tank to the preforms within the autoclave.

Abstract: Process for fabricating a preform, wherein a fiber preform is infiltrated with molten silicon after being contacted with an aqueous silicon carbide particulate slurry containing a dissolved source of carbon and heated to coat the particles with carbon.

Abstract: A method of processing a ceramic preform is disclosed having the steps of: coating with a preceramic polymer at least one fabric panel formed of silicon carbide fibers coated with a high temperature boron nitride; shaping the at least one fabric panel into a preliminary preform; curing the preceramic polymer to impart rigidity to the preform, and inserting the rigidized preform into a reactor without tooling for a chemical vapor infiltration process to form the ceramic preform.

Abstract: A method of processing a porous ceramic preform is disclosed comprising: partially infiltrating interconnected pores of a ceramic preform with an organic fluid, converting the organic fluid on pore surfaces of preform to a carbon film, and injecting silicon into the pores with the carbon film of the preform.

Abstract: A method for manufacturing a preform having a desirably uniform distribution of structural forms (for example and without limitation, particles, flakes, and fibers) therethrough. The method according to the present invention includes using an electrical charge reaction between cationic and anionic agents (such as, without limitation, cationic and anionic polymers) to cause the structural forms to floc or clump together in a mass in which the structural forms are desirably uniformly distributed therethrough. The flocculent mass is then dewatered and/or dried to form a preform that is ready for further processing.

Abstract: A method for manufacturing a preform having a desirably uniform distribution of structural forms (for example and without limitation, particles, flakes, and fibers) therethrough. The method according to the present invention includes using an electrical charge reaction between cationic and anionic agents (such as, without limitation, cationic and anionic polymers) to cause the structural forms to floc or clump together in a mass in which the structural forms are desirably uniformly distributed therethrough. The flocculent mass is then dewatered and/or dried to form a preform that is ready for further processing.

Abstract: A method for manufacturing a preform having a desirably uniform distribution of structural forms (for example and without limitation, particles, flakes, and fibers) therethrough. The method according to the present invention includes using an electrical charge reaction between cationic and anionic agents (such as, without limitation, cationic and anionic polymers) to cause the structural forms to floc or clump together in a mass in which the structural forms are desirably uniformly distributed therethrough. The flocculent mass is then dewatered and/or dried to form a preform that is ready for further processing.

Abstract: A method for manufacturing a preform having a desirably uniform distribution of structural forms (for example and without limitation, particles, flakes, and fibers) therethrough. The method according to the present invention includes using an electrical charge reaction between cationic and anionic agents (such as, without limitation, cationic and anionic polymers) to cause the structural forms to floc or clump together in a mass in which the structural forms are desirably uniformly distributed therethrough. The flocculent mass is then dewatered and/or dried to form a preform that is ready for further processing.