A method of forming a composite article may include impregnating an inorganic fiber porous preform with a first slurry composition. The slurry composition includes particles, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to substantially immobilize the particles and yield a gelled article. The method also includes impregnating the gelled article with a second solution that includes a high char-yielding component, and pyrolyzing the high char-yielding component to yield carbon and form a green composite article. The green composite article is then infiltrated with a molten metal or alloy infiltrant to form the composite article. The molten infiltrant reacts with carbon, and the final composite article may include less residual metal or alloy than a composite article formed without using the second solution.

A method of fabricating a ceramic matrix composite includes generating a stream of vaporized precursor and, optionally, a vaporized rare earth element. The vaporized precursor is a precursor of either silicon carbide or silicon nitride. The stream flows for one or more periods of time through a chamber that contains a fibrous structure such that the fibrous structure is exposed to the stream. The fibrous structure initially contains no silicon carbide matrix or silicon nitride matrix. The vaporized precursor deposits over the period of time on the fibrous structure as a substantially fully dense ceramic matrix of either the silicon carbide or the silicon nitride. For at least a portion of the period of time, the vaporized rare earth element is included in the stream such that the ceramic matrix deposited during that time includes dispersed rare earth element.

A method of producing an enhanced ceramic matrix composite includes applying a tackifier compound to a fiber preform. The tackifier compound includes inorganic filler particles. The method further includes modifying the tackifier compound such that the inorganic filler particles remain interspersed throughout the fiber preform, and occupy pores of fiber preform.

The present application provides methods and apparatus for processing ceramic fibers for the manufacture of ceramic matrix composites (CMCs). One method may include providing at least one frame including a planar array of unidirectional ceramic fibers extending across a void thereof. The method may further include depositing a coating on the ceramic fibers of the at least one frame via a chemical vapor deposition (CVD) process. The method may also include impregnating the coated ceramic fibers with a slurry including a ceramic matrix precursor composition to form at least one CMC prepreg, such as a prepreg tape. The ceramic fibers may be substantially SiC fibers, for example.

A method including infiltrating a porous fiber preform with a slurry including a carrier fluid and a first plurality of solid particles wherein the first plurality of solid particles includes at least a first ceramic material, drying the slurry to form a greenbody preform, machining the greenbody preform to a target dimension, depositing a protective layer precursor including a second plurality of solid particles on the machined greenbody preform wherein the second plurality of solid particles includes at least a second ceramic material, and infiltrating the machined greenbody preform with a molten infiltrant to form a composite article including an integral protective layer.

A method of making a fiber preform for ceramic matrix composite (CMC) fabrication comprises laminating an arrangement of fibers between polymer sheets comprising an organic polymer, which may function as a fugitive binder during fabrication, to form a flexible prepreg sheet. A plurality of the flexible prepreg sheets are laid up in a predetermined geometry to form a stack, and the stack is heated to soften the organic polymer and bond together the flexible prepreg sheets into a bonded prepreg structure. Upon cooling of the bonded prepreg structure, a rigid preform is formed. The rigid preform is heated at a sufficient temperature to pyrolyze the organic polymer. Thus, a porous preform that may undergo further processing into a CMC is formed.

Systems and methods for manufacturing unidirectional fiber prepreg tapes for CMC articles are provided. In one exemplary aspect, the method includes casting a matrix material on a carrier film to form a matrix film. The matrix material of the matrix film is then allowed to dry for a predetermined time. The matrix film is then wrapped on a drum and the matrix material is wet to a predetermined viscosity with a solvent. Thereafter, a fiber tow that includes of a plurality of fibers is wound about the drum so that the fiber tow penetrates into the matrix material and the matrix material impregnates the fiber tow to form the prepreg tape.

A method for improving thermal efficiency of a heating device that reduces an amount of heat flowing out from a heating device 11 to the outside by installing a heat-resistant inorganic conjugated molded product 16 in and along a pathway 15 for heated gas generated from the heating device 11 without interrupting the flow of heated gas passing the pathway 15, heating the inorganic conjugated molded product 16 with the heated gas, and putting radiation heat from the heated inorganic conjugated molded product 16 back into the heating device 11, the inorganic conjugated molded product 16 being provided with an interior layer and an exterior layer, the exterior layer consisting of a coverture for inorganic materials that protects the interior layer from heated gas.

The invention concerns a method for surface treatment of a ceramic material in powder form, wherein said method comprising the step of providing a powder formed of a plurality of particles of the ceramic material to be treated, and wherein said ceramic powder particles are subjected to an ion implantation process by directing towards an external surface of said particles a beam of singly or multiply charged ions produced by a charge of singly or multiply charged ions, for example of the electron cyclotron resonance ECR type, wherein said particles have a generally polyhedral shape.

The invention also concerns a material in powder form, formed of a plurality of particles having a ceramic external layer and a ceramic core, wherein said particles have a generally polyhedral shape.

A method of forming a composite article may include impregnating an inorganic fiber porous preform with a first slurry composition. The slurry composition includes particles, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to substantially immobilize the particles and yield a gelled article. The method also includes impregnating the gelled article with a second solution that includes a high char-yielding component, and pyrolyzing the high char-yielding component to yield carbon and form a green composite article. The green composite article is then infiltrated with a molten metal or alloy infiltrant to form the composite article. The molten infiltrant reacts with carbon, and the final composite article may include less residual metal or alloy than a composite article formed without using the second solution.