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.

In some examples, article used as a component for a turbine engine that operates in a high temperature environment. The article may include: a ceramic or ceramic matrix composite (CMC) substrate; and a coating on the ceramic or the CMC substrate, wherein the coating defines an outer surface of the article. The coating includes a plurality of surface features defining channels on the outer surface of the article. The channels are configured to modify a flow of molten Calcia-Magnesia-Alumina Silicate (CMAS) over the outer surface of the coating in a gas flow over the outer surface of the article to reduce accumulation of the molten CMAS on the outer surface of the article.

In some examples, article used as a component for a turbine engine that operates in a high temperature environment. The article may include: a ceramic or ceramic matrix composite (CMC) substrate; and a coating on the ceramic or the CMC substrate, wherein the coating defines an outer surface of the article. The coating includes a plurality of surface features defining channels on the outer surface of the article. The channels are configured to modify a flow of molten Calcia-Magnesia-Alumina Silicate (CMAS) over the outer surface of the coating in a gas flow over the outer surface of the article to reduce accumulation of the molten CMAS on the outer surface of the article.

A full-fiber burner brick and a preparation method thereof, comprising mixing alumina crystal fiber and amorphous ceramic fiber with both of them being a combination of fibers of different lengths gradations, and moreover adding fine powder fillers of different particle size gradations and supplementing other additives. This enables the internal structure of the product more uniform, increases the bulk density of the product, and also benefits the suction filterability of fiber cotton blank, and is conducive to forming and improving the strength of the blank. The surface of the brick body is further provided with a coating, which can effectively protect the cotton fiber of the brick body fiber from harsh environments, improve its high temperature resistance, and help to extend the service life of the burner brick.

A method and system for treating calcium-based stone having a surface to be treated for corrosion and stain resistance is provided. The system comprises a sanding unit to sand the surface of the calcium-based stone with a grit size of 40 to 100 to promote coating adhesion. The system further comprises a coating unit to coat the surface of the calcium-based stone with a predetermined amount of a coating material for corrosion and stain resistance defining an uncured coating on the surface. The system further comprises a curing unit to cure the uncured coating on the surface with a photo-initiator defining a cured coating on the surface. The system further comprises a polishing unit to polish the cured coating on the surface with a grit size of 1000 to 3000. The system further comprises a buffing unit to buff the cured coating on the surface with a fabric defining a treated surface of the calcium-based stone.

A method and system for treating calcium-based stone having a surface to be treated for corrosion and stain resistance is provided. The system comprises a sanding unit to sand the surface of the calcium-based stone with a grit size of 40 to 100 to promote coating adhesion. The system further comprises a coating unit to coat the surface of the calcium-based stone with a predetermined amount of a coating material for corrosion and stain resistance defining an uncured coating on the surface. The system further comprises a curing unit to cure the uncured coating on the surface with a photo-initiator defining a cured coating on the surface. The system further comprises a polishing unit to polish the cured coating on the surface with a grit size of 1000 to 3000. The system further comprises a buffing unit to buff the cured coating on the surface with a fabric defining a treated surface of the calcium-based stone.

A method and system for treating calcium-based stone having a surface to be treated for corrosion and stain resistance is provided. The system comprises a sanding unit to sand the surface of the calcium-based stone with a grit size of 40 to 100 to promote coating adhesion. The system further comprises a coating unit to coat the surface of the calcium-based stone with a predetermined amount of a coating material for corrosion and stain resistance defining an uncured coating on the surface. The system further comprises a curing unit to cure the uncured coating on the surface with a photo-initiator defining a cured coating on the surface. The system further comprises a polishing unit to polish the cured coating on the surface with a grit size of 1000 to 3000. The system further comprises a buffing unit to buff the cured coating on the surface with a fabric defining a treated surface of the calcium-based stone.

An article includes a ceramic material and features a machined surface that is characteristic of cold ablation laser machining, and the machined surface exhibits no visible oxidation. A laser machining apparatus and technique is based on cold-ablation, but is modified or augmented with an inert assist gas to minimize deleterious surface modifications and mitigate oxide formation associated with laser machining.

A ceramic core (40) for an investment casting process (80) including a subsurface internal channel (50) for the introduction of leachate (98) to improve the effectiveness of a leaching process used to remove the core (94) from a cast alloy component (100). The subsurface internal channel may be completely hollow, or it may include one or more ribs (54). The core may be formed (82) using a 3D printing process wherein a carrier material (68) is deposited in a central region of the channel for the purpose of supporting an overlying layer (62) of core material, with the carrier material later being removed to reveal the hollow internal channel (52).

A method for making a ceramic matrix composite component includes densifying a fibrous preform of the component with a ceramic matrix to form an intermediate component; infiltrating a hole in the intermediate component with an infiltrate material comprising a solid and a metallic alloy whose reaction forms a carbide, silicide, boride or combination thereof, heating the infiltrate material to a temperature in excess of a melting point of the metallic alloy; and sequentially cooling regions of the hole starting from an interior end of the hole to the outer surface of the intermediate component to form a solidified through-thickness reinforcement element. The hole extends in a through-thickness direction and is open to an exterior surface of the intermediate component.