Abstract: An article includes a silicon oxycarbide-based layer that has Si, O, and C in a covalently bonded network. The silicon oxycarbide-based layer has first and second opposed surfaces. A calcium-magnesium alumino-silicate-based layer is interfaced with the first surface of the silicon oxycarbide-based layer.

Abstract: A ceramic matrix composite includes a plurality of ceramic fibers and an interface coating disposed on the plurality of ceramic fibers. The interface coating includes a carbon-based layer disposed on each ceramic fiber of the plurality of ceramic fibers and a boron-nitride based layer disposed on the first carbon-based layer. The ceramic matrix composite also includes a ceramic matrix surrounding the plurality of ceramic fibers. A ceramic matrix composite and a method of forming a ceramic matrix composite component are also disclosed.

Abstract: A ceramic matrix composite includes a plurality of ceramic fibers and an interface coating disposed on the plurality of ceramic fibers. The interface coating includes a carbon-based layer disposed on each ceramic fiber of the plurality of ceramic fibers and a boron-nitride based layer disposed on the first carbon-based layer. The ceramic matrix composite also includes a ceramic matrix surrounding the plurality of ceramic fibers. A ceramic matrix composite and a method of forming a ceramic matrix composite component are also disclosed.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix of barium-magnesium alumino-silicate or SiO2, a dispersion of silicon oxycarbide particles in the matrix, and a dispersion of particles, of the other of barium-magnesium alumino-silicate or SiO2, in the matrix.

Abstract: A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone comprised of an exterior surface of the ceramic matrix composite and pores that extend from the exterior surface into the ceramic matrix composite. A glaze material seals the surface zone within the pores of the surface zone and on the exterior surface of the surface zone as an exterior glaze layer on the ceramic matrix composite. The glaze material is a glass or glass-ceramic material. The ceramic matrix composite includes an interior zone under the surface zone, and the interior zone is free of any of the glaze material and has a greater porosity than the surface zone.

Abstract: A method for coating a ceramic matrix composite substrate with an environmental barrier coating includes the steps of: treating a surface of a ceramic matrix composite substrate to adjust wettability of the surface; and applying an aqueous slurry-based environmental barrier coating to the surface. The treating step can be a plasma treatment to remove organic contaminants, and can also be a treatment to modify oxidative state of the surface. The treatment can produce a surface for treatment that is hydrophilic and has a contact angle with aqueous-slurry coating materials of less than 40 degrees.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix of barium-magnesium alumino-silicate or SiO2, a dispersion of silicon oxycarbide particles in the matrix, and a dispersion of particles, of the other of barium-magnesium alumino-silicate or SiO2, in the matrix.

Abstract: An environmental barrier coating, comprising a substrate containing silicon; an environmental barrier layer applied to the substrate; the environmental barrier layer comprising an oxide matrix; an oxidant getter phase interspersed throughout the oxide matrix; and a self-healing phase interspersed throughout the oxide matrix.

Abstract: A ceramic matrix composite includes a plurality of ceramic fibers and an interface coating disposed on the plurality of ceramic fibers. The interface coating includes a carbon-based layer disposed on each ceramic fiber of the plurality of ceramic fibers and a boron-nitride based layer disposed on the first carbon-based layer. The ceramic matrix composite also includes a ceramic matrix surrounding the plurality of ceramic fibers. A ceramic matrix composite and a method of forming a ceramic matrix composite component are also disclosed.

Abstract: A disclosed method of forming a ceramic article includes forming a pre-ceramic polymer article within a mold tool, and performing a first pyrolizing step on the initial pre-ceramic polymer article to form a ceramic article. The method further includes performing at least one pre-heat treatment polymer infiltration and pyrolizing (PIP) cycle on the ceramic article and an initial heat treatment cycle of the ceramic article after the at least one pre-heat treatment PIP cycle. Subsequent PIP cycles and heat treatment cycles are performed in combination to form a ceramic article including a desired density.

Abstract: An article includes a silicon oxycarbide-based layer that has Si, O, and C in a covalently bonded network. The silicon oxycarbide-based layer has first and second opposed surfaces. A calcium-magnesium alumino-silicate-based layer is interfaced with the first surface of the silicon oxycarbide-based layer.

Abstract: In a method for repairing a coated article, the article has: a ceramic matrix composite (CMC) substrate; and a coating system having a plurality of layers. A damage site at least partially penetrates at least one of the layers. The method includes: applying a slurry of a repair material to the damage site for repairing a first of the penetrated layers; and after the applying, heating the repair material with a plasma torch.

Abstract: A process of coating a substrate containing silicon with an environmental barrier coating, comprising altering a surface of the substrate and applying an environmental barrier layer to the surface of the substrate.

Abstract: A cover plate for a rotor assembly is disclosed. In various embodiments, the cover plate includes an annular member having a radially inner portion and a radially outer portion with respect to a longitudinal axis, the radially inner portion including an aft face and an angled forward face, the angled forward face defining a forward face angle with respect to a cylindrical plane that is coaxial with the longitudinal axis, the face angle having a value that is greater than or equal to fifty degrees; a first tab and a second tab disposed proximate the radially inner portion of the annular member; and a slot disposed between the first tab and the second tab.

Abstract: A method of fabricating a ceramic article includes providing a porous body that includes a plurality of fiber bundles that has an intra-bundle porosity and an inter-bundle porosity, infiltrating the intra-bundle porosity and the inter-bundle porosity with a mixture of particles in a liquid carrier, the particles having an average size selected with respect to at least the intra-bundle porosity, removing the liquid carrier from the porous body to deposit the particles in the intra-bundle porosity and in the inter-bundle porosity, infiltrating a preceramic polymer into a remaining intra-bundle porosity and a remaining inter-bundle porosity, and thermally converting the preceramic polymer to a ceramic material.

Abstract: A ceramic article includes a ceramic matrix composite that has a porous reinforcement structure and a ceramic matrix within pores of the porous reinforcement structure. The ceramic matrix composite includes a surface zone comprised of an exterior surface of the ceramic matrix composite and pores that extend from the exterior surface into the ceramic matrix composite. A glaze material seals the surface zone within the pores of the surface zone and on the exterior surface of the surface zone as an exterior glaze layer on the ceramic matrix composite. The glaze material is a glass or glass-ceramic material. The ceramic matrix composite includes an interior zone under the surface zone, and the interior zone is free of any of the glaze material and has a greater porosity than the surface zone.

Abstract: A cover plate for a rotor assembly is disclosed. In various embodiments, the cover plate includes an annular member having a radially inner portion and a radially outer portion with respect to a longitudinal axis, the radially inner portion including an aft face and an angled forward face, the angled forward face defining a forward face angle with respect to a cylindrical plane that is coaxial with the longitudinal axis, the face angle having a value that is greater than or equal to fifty degrees; a first tab and a second tab disposed proximate the radially inner portion of the annular member; and a slot disposed between the first tab and the second tab.

Abstract: An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix of barium-magnesium alumino-silicate or SiO2, a dispersion of silicon oxycarbide particles in the matrix, and a dispersion of particles, of the other of barium-magnesium alumino-silicate or SiO2, in the matrix.

Abstract: An environmental barrier coating, comprising a substrate containing silicon; an environmental barrier layer applied to the substrate; the environmental barrier layer comprising an oxide matrix; an oxidant getter phase interspersed throughout the oxide matrix; and a self-healing phase interspersed throughout the oxide matrix.

Abstract: A method for coating a ceramic matrix composite substrate with an environmental barrier coating includes the steps of: treating a surface of a ceramic matrix composite substrate to adjust wettability of the surface; and applying an aqueous slurry-based environmental barrier coating to the surface. The treating step can be a plasma treatment to remove organic contaminants, and can also be a treatment to modify oxidative state of the surface. The treatment can produce a surface for treatment that is hydrophilic and has a contact angle with aqueous-slurry coating materials of less than 40 degrees.