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 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.

This relates to a turbine blade comprising a preformed fibrous fabric of fibres consisting of carbon, silicon carbide or rhenium fixed with a binder resin, and wherein the preformed and fixed fibrous fabric is coated and infiltrated, respectively, with B.sub.4C, wherein the preformed fibrous fabric that has been fixed and coated and infiltrated, respectively, with B.sub.4C further has a multilayer coating consisting of at least one layer of silicon carbide and at least one layer of a metal boride, a metal nitride or a metal carbide, and wherein an oxide ceramic is applied over the multilayer coating. The turbine blade is resistant to high temperatures and is particularly well suited for use in a gas turbine. Methods for producing the turbine blade are also described.

A coated fiber structure for use in a ceramic matrix composite includes a fiber and an interface coating system applied to the fiber. The interface coating system includes a first coating layer disposed on the fiber and a second coating layer disposed on the first coating layer. The first coating layer comprises a rare earth nitride or a rare earth carbide. The second coating layer comprises silicon-doped boron nitride.

A method for uniformly distributing particulate matter in a fiber reinforcement of a CMC material, comprising: providing at least one preform of at least one fiber reinforcement; infiltrating the preform with at least one slurry containing at least one particulate material and at least one solvent to form at least one slurry infiltrated preform comprising the particulate material; freezing the slurry infiltrated preform containing the particulate material to form at least one frozen slurry infiltrated preform containing the particulate material; sublimating the frozen slurry infiltrated preform including the particulate material to form at least one structural support comprising the particulate material uniformly distributed thereupon within at least one sublimated slurry infiltrated preform; and melt-infiltrating with at least one metal, at least one metalloid, at least one metal alloy, or at least one metalloid alloy, the sublimated slurry infiltrated preform containing the structural support to form a melt-infiltrated CMC material.