A method for manufacturing a metal bladed wheel of a turbomachine reinforced by an insert made of metal matrix composite material, includes winding the ceramic fibers around a mandrel in order to form the insert, the ceramic fibers being surrounded by a material constituting the matrix; and spark plasma sintering the insert with a powder of metal constituting the bladed wheel to be manufactured.

A gas turbine engine component includes a ceramic matrix composite (CMC) body that includes an interior surface that defines a blind cavity. A barrier coating is disposed on an exterior of the CMC body. A ceramic body in the blind cavity lines at least a portion of the interior surface of the CMC body. The ceramic body defines an open, interconnected network of pores.

A method to produce a ceramic matrix composite with controlled surface characteristics includes: applying a scrim ply to a surface of a fiber preform, where the fiber preform includes silicon carbide fibers coated with boron nitride; infiltrating the fiber preform and the scrim ply with a slurry, thereby forming an impregnated ply on an impregnated fiber preform; infiltrating the impregnated fiber preform and the impregnated ply with a melt comprising silicon, and then cooling, thereby forming a ceramic matrix composite having a ceramic surface layer thereon, where the ceramic surface layer has a predetermined thickness and is devoid of boron; machining or grit blasting the ceramic surface layer to form an intermediate layer suitable for coating; and depositing an environmental barrier coating on the intermediate layer. Thus, a ceramic matrix composite coated with the environmental barrier coating is formed with the intermediate layer in between.

A turbomachine engine including a high-pressure compressor, a high-pressure turbine, a combustion chamber in flow communication with the high-pressure compressor and the high-pressure turbine, and a power turbine in flow communication with the high-pressure turbine. At least one of the high-pressure compressor, the high-pressure turbine, and the power turbine comprises a ceramic matrix composite (CMC) material. The turbomachine engine includes a low-pressure shaft coupled to the power turbine and characterized by a midshaft rating (MSR) between two hundred (ft/sec).sup.1/2 and three hundred (ft/sec).sup.1/2. The low-pressure shaft has a redline speed between fifty and two hundred fifty feet per second (ft/sec). The turbomachine engine is configured to operate up to the redline speed without passing through a critical speed associated with a first-order bending mode of the low-pressure shaft.

A seal assembly includes a carbon seal that has a sealing surface. A seal seat has a sealing surface and is positioned for rotation relative to the carbon seal. A diamond-like carbon coating at least partially forms the sealing surface on the seal seat.

An article for high temperature service is presented herein. One embodiment is an article including a substrate having a silicon-bearing ceramic matrix composite; and a layer disposed over the substrate, wherein the layer includes silicon and a dopant, the dopant including aluminum. In another embodiment, the article includes a ceramic matrix composite substrate, wherein the composite includes a silicon-bearing ceramic and a dopant, the dopant including aluminum; a bond coat disposed over the substrate, where the bond coat includes elemental silicon, a silicon alloy, a silicide, or combinations including any of the aforementioned; and a coating disposed over the bond coat, the coating including a silicate (such as an aluminosilicate or rare earth silicate), yttria-stabilized zirconia, or a combination including any of the aforementioned.

An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix phase and a network of gettering particles in the matrix phase. The gettering particles have an average maximum dimension between about 30 and 70 microns. The gettering particles have maximum dimensions that range from about 1 to 100 microns, and a dispersion of barium-magnesium alumino-silicate particles in the matrix phase. A composite material and a method of applying a barrier layer to a substrate are also disclosed.

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 SiO.sub.2, a dispersion of silicon oxycarbide particles in the matrix, and a dispersion of particles, of the other of barium-magnesium alumino-silicate or SiO.sub.2, in the matrix.

A method of forming a ceramic matrix composite component having an internal cooling circuit includes wrapping at least a first sheet around a first mandrel, wrapping at least a second sheet around a second mandrel, creating a first plurality of holes in the first sheet corresponding to a plurality of openings in the first mandrel, creating a second plurality of holes in the second sheet corresponding to a plurality of openings in the second mandrel, aligning the first mandrel and the second mandrel such that the first plurality of holes face and are aligned with the second plurality of holes, wrapping at least a third sheet around both the first mandrel and second mandrel to form a preform, the preform comprising each of the first sheet, the second sheet, and the third sheet, and densifying the preform. The first sheet, second sheet, and third sheet are formed from a ceramic fiber material.

The present invention relates to a protective layer against CMAS, to a CMAS-resistant article comprising the protective layer according to the invention, and to a process for preparing a corresponding article.