A process for densification of a ceramic matrix composite comprises forming a reinforcing ceramic continuous fiber stack having a central zone bounded by an outer zone adjacent; locating first particles within the central zone; coating the first particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; locating second particles within the outer zone; coating the second particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; forming the stack into a predetermined three dimensional shape; and densifying the stack.

In some examples, a technique for infiltrating a porous preform with a slurry to form an infiltrated-preform, where the slurry includes a plurality of solid particles, where the plurality of solid particles include a plurality of fine ceramic particles defining an average fine particle diameter, a plurality of coarse ceramic particles defining an average coarse particle diameter, and a plurality of diamond particles, where the average fine particle diameter is less than the average coarse particle diameter, and infiltrating the infiltrated-preform with a molten metal infiltrant to form a ceramic matrix composite (CMC) article.

A fiber comprises a bulk material comprising one or more materials selected from the group consisting of carbon, silicon, boron, silicon carbide, and boron nitride; and a metal whose affinity for oxygen is greater than the affinity for oxygen of any of the one or more materials. The metal may be selected from the group consisting of beryllium, titanium, hafnium and zirconium. At least a first portion of the metal may be present in un-oxidized form at the entrance to and/or within grain boundaries within the fiber. A method of improving at least one of the strength, creep resistance, and toughness of a fiber comprises adding to a fiber, initially comprising a bulk material having a first affinity for oxygen, a metal that has a second affinity for oxygen higher than the first affinity. The metal may be selected from the group consisting of beryllium, titanium, hafnium and zirconium.

Disclosed is a method for controlling a microstructure of an inorganic material includes providing a structure that has a first region of an inorganic material having a first microstructure and a second region that is thermally responsive to electromagnetic radiation, the second region being adjacent the first region, and indirectly heating the first region by thermally activating the second region, using electromagnetic radiation, to generate heat. The generated heat converts the first microstructure of the inorganic material to a second, different microstructure. The method can be applied to control a microstructure of an inorganic coating on an inorganic fiber.

Methods and apparatus for depositing material on a continuous substrate are provided herein. In some embodiments, an apparatus for processing a continuous substrate includes: a first chamber having a first volume; a second chamber having a second volume fluidly coupled to the first volume; and a plurality of process chambers, each having a process volume defining a processing path between the first chamber and the second chamber, wherein the process volume of each process chamber is fluidly coupled to each other, to the first volume, and to the second volume, and wherein the first chamber, the second chamber, and the plurality of process chambers are configured to process a continuous substrate that extends from the first chamber, through the plurality of process chambers, and to the second chamber.

A high-temperature-steam-oxidation-resistive coated reinforcement fiber applicable to a fiber reinforced composite, is provided with: a reinforcement fiber; a coating layer covering the reinforcement fiber and including a rare-earth silicate; an exfoliative layer intervening in an interface between the coating layer and the reinforcement fiber; and a supplemental coating layer covering the reinforcement fiber, the exfoliative layer and the coating layer.

The invention relates to a method for producing a hollow part made of a ceramic matrix composite material comprising the steps of: shaping a hollow fibrous preform, a core of oxidizable material being housed or inserted into the preform (E1); consolidating said preform (E3, E4); and extracting the core by oxidising said core (E5).

A method of forming a moisture-tolerant coating on a silicon carbide fiber includes exposing a silicon carbide fiber to a gaseous N precursor comprising nitrogen at an elevated temperature, thereby introducing nitrogen into a surface region of the silicon carbide fiber, and exposing the silicon carbide fiber to a gaseous B precursor comprising boron at an elevated temperature, thereby introducing boron into the surface region of the silicon carbide fiber. Silicon-doped boron nitride is formed at the surface region of the silicon carbide fiber without exposing the silicon carbide fiber to a gaseous Si precursor comprising Si. Thus, a moisture-tolerant coating comprising the silicon-doped boron nitride is grown in-situ on the silicon carbide fiber.

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 blade for a gas turbine engine, and methods of manufacture of such a blade having a continuous density gradient so that the portion of the blade nearest the rotator shaft is of a higher density than the portion of the blade furthest from the rotator shaft.