A method of controlling a substrate etching process includes disposing a bottom surface or a top surface of a substrate adjacent to volume of etching fluid to produce an etchant-substrate interface and heating the etchant-substrate interface via spatially controlled electromagnetic radiation. The method also includes transmitting a monitoring beam through the substrate, the substrate and volume of etching fluid being at least partially transparent at the wavelength range of the monitoring beam and measuring a property of the substrate surface during the substrate etching process via the monitoring beam to produce a real-time measured property for the substrate. A corresponding etching system and computer-program product is also disclosed herein.

A method of improving surface roughness of ceramic matrix composites (CMCs) is provided. The method includes completing a formation of the CMCs and a chemical vapor infiltration (CVI) process to initially coat the CMCs, inspecting a CMC surface, identifying, from a result of the inspecting, a defect in the CMC surface that negatively impacts a surface roughness characteristic thereof, locally targeting and ablating the defect and re-inspecting the CMC surface to ensure that the defect is correct.

A method for manufacturing a ceramic substrate that includes preparing a plurality of ceramic green sheets, at least one of the plurality of ceramic green sheets having a disappearance material that disappears by firing in a recessed portion formation planned region of the at least one of the plurality of ceramic green sheets; forming a mother multilayer body by laminating the plurality of ceramic green sheets such that the at least the one ceramic green sheet having the disappearance material is positioned on an uppermost layer of the mother multilayer body; and forming a recessed portion in the mother multilayer body before firing by pressing the recessed portion formation planned region of the mother multilayer body.

A method of making a ceramic device with a controlled roughness includes using a defocused laser beam to roughen a surface of a ceramic substrate, and removing one or more portions of the roughened surface without removing all of the roughened surface. If desired, the ceramic device may include reaction-bonded silicon carbide, and an opening may be formed in the device so that the device can be used to apply a clamping suction to a wafer surface. A ceramic surface with a controlled roughness is also disclosed. The defocused laser beam may be used to make the surface rough enough to prevent it from sticking to a mating element, and to have adequate wear resistance, but not so rough as to prevent the formation of sufficient suction to clamp the surface to a mating element.

A method of making a ceramic matrix composite according to an exemplary embodiment of this disclosure, among other possible things includes forming a ceramic matrix composite component by infiltrating an array of ceramic-based fibers with a ceramic-based matrix. The array of ceramic-based fibers forms a surface that includes gaps between adjacent ones of the fibers. The method also includes applying a paste including filler particles and filler matrix in a carrier fluid to the surface of the ceramic-based fibers that includes the gaps such that the paste fills the gaps and removing the carrier fluid to leave behind a filler including the filler particles and the filler matrix in the gaps. A ceramic matrix composite component is also disclosed.

A method of making a ceramic matrix composite according to an exemplary embodiment of this disclosure, among other possible things includes forming a ceramic matrix composite component by infiltrating an array of ceramic-based fibers with a ceramic-based matrix. The array of ceramic-based fibers forms a surface that includes gaps between adjacent ones of the fibers. The method also includes applying a paste including filler particles and filler matrix in a carrier fluid to the surface of the ceramic-based fibers that includes the gaps such that the paste fills the gaps and removing the carrier fluid to leave behind a filler including the filler particles and the filler matrix in the gaps. A ceramic matrix composite component is also disclosed.

A method of forming an aerodynamic component for use in a gas turbine engine using ceramic matrix composites (CMCs) is provided. The method includes executing a full densification of the CMCs once a final shape of the aerodynamic component is achieved, identifying first and second sectors of an exterior surfaces of the aerodynamic component which have a surface roughness of less than a first roughness level and identifying second sectors of the exterior surface of the component which have a surface roughness of greater than a second roughness level, machining the first sectors to increase the surface roughness to greater than the first roughness level and machining the second sectors to decrease the surface roughness to less than the second roughness level.

A method for processing a component is provided and includes masking a first portion of the component with a maskant. The maskant includes a slurry having a plurality of particles in a fluid carrier. The plurality of particles comprises at least one of silicon, carbon, one or more rare earth disilicates, monosilicates or oxides, and combinations thereof. The method includes depositing a silicon-based coating on a second portion of the component via a chemical vapor deposition process and removing the maskant and any overlying silicon-based coating from the first portion of the component.

An example article includes a substrate and a barrier coating on the substrate extending from an inner interface facing the substrate to an outer surface opposite the inner interface. The barrier coating includes a bulk matrix and a plurality of discrete plugs inset within the bulk matrix and dispersed across the outer surface of the barrier coating. An example technique includes forming the barrier coating on the substrate of a component.

A ceramic spinner and a method of making the same is provided. The ceramic spinner includes: a top portion with a first opening, the first opening having a first diameter; a base portion with a second opening, the second opening having a second diameter smaller than the first diameter; a cylindrical portion extending between the top portion and the base portion, the cylindrical portion including a peripheral outer wall, a peripheral inner wall, and a plurality of through holes extending between the peripheral outer wall and the peripheral inner wall. The cylindrical portion may include a material having a module of rupture (MOR) exceeding 100 MPa, a Mohs hardness exceeding 8, or a Young's Modulus exceeding 250 GPa, or any combinations thereof.