A method of producing a ceramic matrix composite including a protective ceramic coating thereon comprises applying a surface slurry onto an outer surface of an impregnated fiber preform. The surface slurry includes particulate ceramic solids dispersed in a flowable preceramic polymer comprising silicon, and the impregnated fiber preform comprises a framework of ceramic fibers loaded with particulate matter. The flowable preceramic polymer is cured, thereby forming on the outer surface a composite layer comprising a cured preceramic polymer with the particulate ceramic solids dispersed therein. The cured preceramic polymer is then pyrolyzed to form a porous ceramic layer comprising silicon carbide, and the impregnated fiber preform and the porous ceramic layer are infiltrated with a molten material comprising silicon. After infiltration, the molten material is cooled to form a ceramic matrix composite body with a protective ceramic coating thereon.

An airfoil includes a ceramic matrix composite airfoil core that defines an airfoil portion and a root portion. The ceramic matrix composite airfoil core is subject to core thermal growth. A platform includes a ceramic matrix composite that wraps around the root portion. The platform is subject to platform thermal growth. A buffer layer is located between the root portion and the platform. The buffer layer absorbs a mismatch between the core thermal growth and the platform thermal growth.

An airfoil includes a ceramic matrix composite airfoil core that defines an airfoil portion and a root portion. The ceramic matrix composite airfoil core is subject to core thermal growth. A platform includes a ceramic matrix composite that wraps around the root portion. The platform is subject to platform thermal growth. A buffer layer is located between the root portion and the platform. The buffer layer absorbs a mismatch between the core thermal growth and the platform thermal growth.

In some examples, a method including depositing a plurality of particles on a ceramic or ceramic matrix composite (CMC) substrate to form a barrier coating on the ceramic or CMC substrate, the plurality of particles including a silica-rich rare earth (RE) disilicate material and a second material, wherein the silica-rich RE disilicate material includes excess silica compared to a stoichiometric RE disilicate material, wherein the barrier coating includes a first domain including the silica-rich RE disilicate material and a second phase, the second phase being disposed at grain boundaries, splat boundaries, or both of the barrier coating.

In some examples, a method including depositing a plurality of particles on a ceramic or ceramic matrix composite (CMC) substrate to form a barrier coating on the ceramic or CMC substrate, the plurality of particles including a silica-rich rare earth (RE) disilicate material and a second material, wherein the silica-rich RE disilicate material includes excess silica compared to a stoichiometric RE disilicate material, wherein the barrier coating includes a first domain including the silica-rich RE disilicate material and a second phase, the second phase being disposed at grain boundaries, splat boundaries, or both of the barrier coating.

A method for manufacturing a pillar-shaped honeycomb structure filter including a step of preparing a pillar-shaped honeycomb structure having a plurality of first cells and a plurality of second cells that are alternately arranged adjacent to each other with a porous partition wall interposed therebetween; a step of adhering ceramic particles containing 50% by mass or more in total of one or two selected from SiC and SiN to a surface of the first cells; and a step of performing a heat-oxidation treatment on the pillar-shaped honeycomb structure in which the ceramic particles are adhered to the surface of the first cells to form a porous film comprised of the ceramic particles having an oxide film thereon so as to satisfy: (1) 0.05≤T≤0.5; (2) 0.05≤T/D50; and (3) 4≤{(W.sub.1−W.sub.0)/W.sub.0×100}/D50.

A method for manufacturing a pillar-shaped honeycomb structure filter including a step of preparing a pillar-shaped honeycomb structure having a plurality of first cells and a plurality of second cells that are alternately arranged adjacent to each other with a porous partition wall interposed therebetween; a step of adhering ceramic particles containing 50% by mass or more in total of one or two selected from SiC and SiN to a surface of the first cells; and a step of performing a heat-oxidation treatment on the pillar-shaped honeycomb structure in which the ceramic particles are adhered to the surface of the first cells to form a porous film comprised of the ceramic particles having an oxide film thereon so as to satisfy: (1) 0.05≤T≤0.5; (2) 0.05≤T/D50; and (3) 4≤{(W.sub.1−W.sub.0)/W.sub.0×100}/D50.

The present invention relates to a method for manufacturing a zirconia slurry for forming porous surfaces on an abutment and a crown of a ceramic implant, the method including: the zirconia pulverization step (step S10) of putting zirconia powder, carbon powder as a foaming agent, and an organic binder in a ball mill and agitating and pulverizing the zirconia, carbon powder, and organic binder to allow the mixed zirconia powder to have nanoparticles; the carbon powder oxidization step (step S20) of heating the zirconia powder mixed with the carbon powder to a temperature of 1200 to 1800° C. and oxidizing the carbon powder to a concentration of 10 to 40 wt % to allow the porous surfaces to be formed on every particle of the zirconia powder; and the degreasing step (step S30) of putting a dispersing agent and a solvent in the zirconia powder whose particles have the porous surfaces to make a zirconia solution and removing the organic binder from the zirconia powder.

The present invention relates to a method for manufacturing a zirconia slurry for forming porous surfaces on an abutment and a crown of a ceramic implant, the method including: the zirconia pulverization step (step S10) of putting zirconia powder, carbon powder as a foaming agent, and an organic binder in a ball mill and agitating and pulverizing the zirconia, carbon powder, and organic binder to allow the mixed zirconia powder to have nanoparticles; the carbon powder oxidization step (step S20) of heating the zirconia powder mixed with the carbon powder to a temperature of 1200 to 1800° C. and oxidizing the carbon powder to a concentration of 10 to 40 wt % to allow the porous surfaces to be formed on every particle of the zirconia powder; and the degreasing step (step S30) of putting a dispersing agent and a solvent in the zirconia powder whose particles have the porous surfaces to make a zirconia solution and removing the organic binder from the zirconia powder.

A gas turbine engine article includes a substrate and an environmental barrier coating (EBC) system disposed on the substrate. The EBC system includes, from the substrate, a dense bond coat layer, a porous bond coat layer, and a topcoat layer in contact with the porous bond coat layer at an interface. The porous bond coat layer includes a matrix, oxygen-scavenging gas-evolution particles dispersed through the matrix, and engineered buffer pores. The oxygen-scavenging gas-evolution particles react with oxygen and generate a gaseous byproduct that diffuses through the interface to escape the EBC system. The engineered buffer pores buffer diffusion of gaseous byproduct to the interface by retaining at least a portion of the gaseous byproduct.