A method of forming a composite article includes impregnating an inorganic fiber preform with a slurry composition. The slurry composition includes a particulate, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to immobilize the particulate and yield a gelled article, and substantially all solvent is removed from the gelled article to form a green composite article. The green composite article is then infiltrated with a molten infiltrant to form the composite article.

A method of melt infiltration for producing a ceramic matrix composite comprises applying a non-wetting coating onto one or more outer surfaces of a porous fiber preform. The non-wetting coating comprises a non-wetting material with which molten silicon has a contact angle of at least about 45. After applying the non-wetting coating, an uncoated portion of the porous fiber preform is immersed into a molten material comprising silicon, and the molten material is infiltrated into the porous fiber preform through the uncoated portion. The non-wetting coating serves as a barrier to inhibit or prevent the molten material from penetrating the one or more outer surfaces. After infiltration of the molten material into the porous fiber preform, the molten material is cooled to form a ceramic matrix composite, and the non-wetting coating is removed.

An article includes a monolithic substrate and a coating on the monolithic substrate. The monolithic substrate is selected from graphite, silicon carbide, silicon carbide nitride, silicon nitride carbide, and silicon nitride. The coating has a free, exposed surface and includes a compound of aluminum (Al), boron (B) and nitrogen (N) in a continuous chemically bonded network having AlN bonds and BN bonds. The compound includes an atom of nitrogen covalently bonded to an atom of boron and an atom of aluminum, and the compound has a composition B.sub.xAl.sub.(1-x)N, where x is 0.001 to 0.999.

A non-woven fabric is provided which includes a three-dimensional array of fibers. The three-dimensional array of fibers includes an array of standing fibers extending perpendicular to a plane of the non-woven fabric and attached to a base substrate, where the base substrate is one or more of an expendable film substrate, a metal base substrate, or a mandrel substrate. Further, the three-dimensional array of fibers includes multiple layers of non-woven parallel fibers running parallel to the plane of the non-woven fiber in between the array of standing fibers in a defined pattern of fiber layer orientations. In implementation, the array of standing fibers are grown to extend from the base substrate using laser-assisted chemical vapor deposition (LCVD).

A method of forming a composite article includes impregnating an inorganic fiber preform with a slurry composition. The slurry composition includes a particulate, a solvent, and a pre-gellant material. Gelling of the pre-gellant material in the slurry composition is initiated to immobilize the particulate and yield a gelled article, and substantially all solvent is removed from the gelled article to form a green composite article. The green composite article is then infiltrated with a molten infiltrant to form the composite article.

Systems and methods for forming ceramic matrix composite (CMC) components are provided. The CMC component includes a reinforcement material having a plurality of filaments that are at least partially electrically conductive. The plurality of filaments are charged by a charging element with an electric charge of the same sign such that adjacent filaments are in an expanded spatial relationship relative to one another while being coated. While in the expanded spatial relationship, the filaments can also be pulled through a matrix slurry.

A method and apparatus for forming a plurality of fibers from (e.g., CVD) precursors, including a reactor adapted to grow a plurality of individual fibers; and a plurality of independently controllable lasers, each laser of the plurality of lasers growing a respective fiber. A high performance fiber (HPF) structure, including a plurality of fibers arranged in the structure; a matrix disposed between the fibers; wherein a multilayer coating is provided along the surfaces of at least some of the fibers with an inner layer region having a sheet-like strength; and an outer layer region, having a particle-like strength, such that any cracks propagating toward the outer layer from the matrix propagate along the outer layer and back into the matrix, thereby preventing the cracks from approaching the fibers. A method of forming an interphase in a ceramic matrix composite material having a plurality of SiC fibers, which maximizes toughness by minimizing fiber to fiber bridging, including arranging a plurality of SiC fibers into a preform; selectively removing (e.g., etching) silicon out of the surface of the fibers resulting in a porous carbon layer on the fibers; and replacing the porous carbon layer with an interphase layer (e.g., Boron Nitride), which coats the fibers to thereby minimize fiber to fiber bridging in the preform.

Disclosed herein are embodiments of systems and method for processing feedstock materials using microwave plasma processing. Specifically, the feedstock materials disclosed herein pertain to metal powders. Microwave plasma processing can be used to spheroidize the metal powders and form metal nitride or metal carbide powders. The stoichiometry of the metal nitride or metal carbide powders can be controlled by changing the composition of the plasma gas and the residence time of the feedstock materials during plasma processing.

A method of melt infiltration for producing a ceramic matrix composite comprises applying a non-wetting coating onto one or more outer surfaces of a porous fiber preform. The non-wetting coating comprises a non-wetting material with which molten silicon has a contact angle of at least about 45. After applying the non-wetting coating, an uncoated portion of the porous fiber preform is immersed into a molten material comprising silicon, and the molten material is infiltrated into the porous fiber preform through the uncoated portion. The non-wetting coating serves as a barrier to inhibit or prevent the molten material from penetrating the one or more outer surfaces. After infiltration of the molten material into the porous fiber preform, the molten material is cooled to form a ceramic matrix composite, and the non-wetting coating is removed.

Methods for forming a ceramic matrix composite (CMC) are generally provided. The method may include melt infiltrating a silicon mixture into a ceramic matrix composite preform, with the silicon mixture including SiGa, SiIn, or a mixture thereof. The silicon mixture may include silicon metal in combination with SiGa, SiIn, or the mixture thereof. Additionally, the silicon mixture may further include B within the SiGa, SiIn, or the mixture thereof (e.g., in the form of SiBGa, SiBIn, or a mixture thereof).