SiC matrix composite material, where heat-resistant long fiber such as carbon fiber is employed as a material for reinforcement and SiC is employed for the matrix, which significantly improves mechanical properties such as strength and toughness. The SiC matrix composite material, includes a SiC matrix and heat-resistant long fiber, wherein the SiC matrix includes both of alpha-type SiC and beta-type SiC, and the alpha-type SiC and the beta-type SiC are detected by micro-region X-ray diffraction with an X-ray beam diameter of no greater than 300 micrometers substantially at every region of every cross-section of the SiC matrix, the beta-type SiC has an average crystallite size that is no greater than 500 nm and greater than an average crystallite size of the alpha-type SiC, and the SiC matrix composite material has a porosity of no greater than 20% by volume.

A method of infiltrating a fiber preform comprises positioning an assembly in a process chamber, where the assembly includes a tool comprising through-holes, a fiber preform constrained within the tool, and a sacrificial preform disposed between the fiber preform and the tool. The sacrificial preform is gas permeable. The process chamber is heated, and gaseous reactants are delivered into the process chamber during the heating. The gaseous reactants penetrate the through-holes of the tool and infiltrate the sacrificial preform and the fiber preform. Deposition of reaction products occurs on exposed surfaces of the fiber preform and the sacrificial preform, and a coating is formed thereon. In addition, the sacrificial preform accumulates excess coating material formed from increased reactions at short diffusion depths. Accordingly, the coating formed on the fiber preform exhibits a thickness variation of about 10% or less throughout a volume of the fiber preform.

A method for producing an article containing silicon carbide as the main constituent includes a plurality of sets of steps of forming a layer of a raw material powder and irradiating the layer with laser light according to three-dimensional model data. The low material powder is a mixture of silicon carbide powder, metallic silicon powder, and carbon powder. The laser light used in the step of irradiation with laser light has a spatial laser power density of 11 J/mm.sup.3 to 50 J/mm.sup.3.

A method for producing an article containing silicon carbide as the main constituent includes a plurality of sets of steps of forming a layer of a raw material powder and irradiating the layer with laser light according to three-dimensional model data. The low material powder is a mixture of silicon carbide powder, metallic silicon powder, and carbon powder. The laser light used in the step of irradiation with laser light has a spatial laser power density of 11 J/mm.sup.3 to 50 J/mm.sup.3.

The disclosure describes a system that includes a controller configured to receive a representation of a three-dimensional geometry of a preform, determine a set of dimensions of the preform from the representation of the preform, and determine dimensions of at least one insert for a fixed tooling based on a dimensional tolerance of the preform, the set of dimensions of the preform, and dimensions of the fixed tooling.

The disclosure describes a system that includes a controller configured to receive a representation of a three-dimensional geometry of a preform, determine a set of dimensions of the preform from the representation of the preform, and determine dimensions of at least one insert for a fixed tooling based on a dimensional tolerance of the preform, the set of dimensions of the preform, and dimensions of the fixed tooling.

A reaction-bonded silicon carbide (SiC) body is produced by: providing a preform including ceramic elements and carbon, and one or more surface features; providing a powder which includes diamond particles and carbon; locating the powder in the surface feature(s); and infiltrating the preform and the powder with molten silicon (Si) to form reaction-bonded SiC in the preform, and to form reaction-bonded SiC coatings on the diamond particles. The present disclosure also relates to a device/component which includes: a main body portion and discrete elements located at least partially within the main body portion. The main body portion may include reaction-bonded SiC and Si, but not diamond, while the discrete elements include diamond particles, reaction-bonded SiC coatings surrounding the diamond particles, and Si. According to the present disclosure, diamond may be advantageously located only where it is needed.

A method for manufacturing a turbine nozzle vane made of ceramic matrix composite material, wherein the vane is manufactured using a first fibrous preform including a hollow central section intended to form a fibrous reinforcement of an airfoil of the vane to be obtained, and a pair of second fibrous preforms each having an opening with a shape of the airfoil of the vane to be obtained.

A method of forming a ceramic matrix composite includes depositing particles on a ceramic fabric formed from a plurality of ceramic tows, applying a binder to at least the particles to form a stabilized ceramic fabric, forming a preform using the stabilized ceramic fabric, and densifying the preform. The ceramic tows are formed from a first material and the particles are formed from at least a second material.

A method of forming a structure comprising a continuous fiber material comprises continuously feeding, through a continuous fiber nozzle assembly of an additive manufacturing tool, a feed material comprising a continuous fiber material and a thermoset resin material, heating or cooling the feed material to maintain a temperature of the feed material to a temperature sufficient to tackify the feed material and at least partially cure the feed material and initiate adhesion of the feed material on a build platform or a previously formed portion of a structure, and moving the continuous fiber nozzle assembly in three dimensions while depositing the feed material on the build platform or the previously formed portion of the structure to form the structure comprising the continuous fiber material extending in three dimensions. Related methods of forming a composite structure, and related tools for additively manufacturing a structure are disclosed.