This invention provides resin formulations which may be used for 3D printing and pyrolyzing to produce a ceramic matrix composite. The resin formulations contain a solid-phase filler, to provide high thermal stability and mechanical strength (e.g., fracture toughness) in the final ceramic material. The invention provides direct, free-form 3D printing of a preceramic polymer loaded with a solid-phase filler, followed by converting the preceramic polymer to a 3D-printed ceramic matrix composite with potentially complex 3D shapes or in the form of large parts. Other variations provide active solid-phase functional additives as solid-phase fillers, to perform or enhance at least one chemical, physical, mechanical, or electrical function within the ceramic structure as it is being formed as well as in the final structure. Solid-phase functional additives actively improve the final ceramic structure through one or more changes actively induced by the additives during pyrolysis or other thermal treatment.

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.

A method of producing a CMC having a smooth surface includes forming a fiber preform; rigidizing the preform with an interphase coating; infiltrating a ceramic slurry into the preform to form a green body; conducting secondary operations on the green body; applying a slurry-based layer onto a portion of the green body; and infiltrating the green body with a molten silicon or silicon alloy, such that the CMC exhibits a smooth surface. The application of the slurry-based surface layer onto the green body includes placing the green body into a tool fixture having upper and lower components, such that a gap is present between the green body and at least one of the upper and lower components; and delivering a surface layer slurry into at least one gap, such that the surface layer slurry forms the slurry-based layer on at least a portion of the green body.

Disclosed is a method of making high temperature fiber including chemically bonding high temperature material to a fiber template at a first temperature to form a precursor fiber and processing the precursor fiber at a second temperature to form the high temperature fiber. The first temperature does not equal the second temperature. Also disclosed are high temperature fibers made by the method.

Disclosed is a method of coating a high temperature fiber including depositing a base material on the high temperature fiber using atomic layer deposition, depositing an intermediate material precursor on the base material using molecular layer deposition, depositing a top material on the intermediate material precursor or the intermediate layer using atomic layer deposition, and heat treating the intermediate precursor. The intermediate material in the final coating includes a structural defect, has lower density than the top material or a combination thereof. Also disclosed are the coated high temperature fiber and a composite including the high temperature fiber.

Disclosed is a method of making high temperature fiber including incorporating an inorganic atom into a polymer precursor fiber to form a modified polymer precursor fiber and converting the modified polymer precursor fiber to a high temperature fiber having a bonded inorganic atom.

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 is provided in which multiple layers are formed. Each of the layers includes at least a first set of ceramic fibers and a second set of ceramic fibers. The first set is arranged at an angle with respect to the second set. The first set and the second set define a plurality of pores therebetween. The layers are arranged on top of each other to form a porous preform. The pores of the layers arranged on top of each other are aligned. The pores define a plurality of channels extending continuously through the porous preform from a first side of the porous preform to a second side of the porous preform. Each channel comprises one inlet at the first side of the porous preform and one outlet at the second side of the porous preform. The porous preform is infiltrated with a matrix material.

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.

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.