Abstract: A gas turbine engine article includes a silicon-containing ceramic wall that has an external combustion gaspath side and an internal side that borders a cooling air cavity. The external combustion gaspath side has an associated combustion gas flow direction there along. An array of cooling holes extends through the silicon-containing ceramic wall and connects the internal side with the external combustion gaspath side. The cooling holes are oriented to discharge cooling air to the external gaspath side in a direction counter to the combustion gas flow direction.

Abstract: Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Abstract: A gas turbine engine article includes a substrate that has a pre-bond surface that includes a serpentine groove. A coating is disposed on the pre-bond surface and mechanically interlocks with the serpentine groove.

Abstract: An adaptive surface texturing method is provided for use with a part formed of ceramic matrix composites (CMCs) to be coated with an environmental barrier coating (EBC). The method includes coating a CMC surface of the part with an initial coating, determining a contour and an undulation pattern of the CMC surface and designing a texturing pattern to follow the contour and the undulation pattern and to be formed in the initial coating based on a thickness of the initial coating and an average particle size of a slurry of the EBC.

Abstract: A gas turbine engine article includes a substrate that has a pre-bond surface that includes a serpentine groove. A coating is disposed on the pre-bond surface and mechanically interlocks with the serpentine groove.

Abstract: A waterjet-guided laser machine includes a laser source, an LED, a waterjet head, and a light sensor. The waterjet head includes a water inlet and a nozzle having an outlet for a discharging a waterjet. There is a laser optical path along which a pulsed laser beam travels to the nozzle outlet. There is also a light beam optical delivery path along which the light beam travels from the LED to the nozzle outlet. The light beam optical delivery path is coincident with the laser optical path in the nozzle. There is a light beam optical return path along which the light beam that is reflected off of a workpiece travels to the light sensor. The light beam optical return path is coincident with the laser optical path inside the nozzle and coincident with the light beam optical delivery path inside the nozzle.

Abstract: A method for fabricating a component according to an example of the present disclosure includes the steps of depositing a stoichiometric precursor layer onto a preform, and densifying the preform by depositing a matrix material onto the stoichiometric precursor layer. An alternate method and a component are also disclosed.

Abstract: A gas turbine engine article includes a silicon-containing ceramic wall that has an external combustion gaspath side and an internal side that borders a cooling air cavity. The external combustion gaspath side has an associated combustion gas flow direction there along. An array of cooling holes extends through the silicon-containing ceramic wall and connects the internal side with the external combustion gaspath side. The cooling holes are oriented to discharge cooling air to the external gaspath side in a direction counter to the combustion gas flow direction.

Abstract: A method of machining cooling holes includes providing a workpiece in which a cooling hole is to be formed. The cooling hole, once formed, defines distinct first and second sections. The workpiece is secured in a fixture that is mounted in a first machine. In the first machine, a laser is used to drill a through-hole in a wall of the workpiece. The through-hole is spatially common to the first and second sections of the cooling hole. After drilling the through-hole, the fixture with the workpiece secured therein is removed from the first machine and mounted in a second machine. In the second machine, ultrasonic machining is used to expand a portion of the through-hole to form the second section. An abrasive slurry used in the process is drained through the through-hole during the ultrasonic machining.

Abstract: A method is provided for machining a workpiece. During this machining method, an aperture is formed in the workpiece using a machining system. The machining system includes an ultrasonic machining device, a slurry delivery device and a controller. The forming of the aperture includes delivering a slurry to an interface between the ultrasonic machining device and the workpiece using the slurry delivery device, and transmitting ultrasonic vibrations into the slurry using the ultrasonic machining device. A feedback parameter is monitored during the forming of the aperture using the controller. A slurry delivery parameter for the slurry delivery device is adjusted during the forming of the aperture based on the feedback parameter using the controller.

Abstract: Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Abstract: A method for machining a ceramic workpiece includes providing a sonotrode that has a transducer and a horn arranged along an axis, and the horn has helical slots and terminates at a tip, bringing the tip into proximity of the ceramic workpiece and providing an abrasive media to a work zone around the tip, using the transducer to produce ultrasonic vibration that axially propagates down the horn and causes axial vibration at the tip, and the helical slots convert a portion of the axial vibration to torsional vibration at the tip, and the axial vibration and the torsional vibration causing the abrasive media to abrade the ceramic workpiece in the work zone and thereby remove a localized portion of the ceramic workpiece.

Abstract: A method for fabricating a component according to an example of the present disclosure includes the steps of depositing a stoichiometric precursor layer onto a preform, and densifying the preform by depositing a matrix material onto the stoichiometric precursor layer. An alternate method and a component are also disclosed.

Abstract: A method of machining includes mounting a component in a drilling machine. The component has a target region where the hole is to be drilled. The component and a jet head are situated relative to each other in a drilling arrangement in which the target region is at a first position that is vertically equal to or vertically above a second position at which the jet head is located. A liquid stream is jetted from the jet head and contains either abrasive particles or a laser beam. The stream impinges the target region, and the abrasive particles or the laser beam cause removal of material from the component to form the hole. The liquid stream rebounds off of the component as back-splash. The drilling arrangement causes gravitational draining of the back-splash from the target region to reduce interference between the back-splash and the liquid stream.

Abstract: Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Abstract: A method comprises discharging from a metal vaporization device a vapor of a metal or a metal precursor to a chemical vapor infiltration device where the chemical vapor infiltration device is in fluid communication with the metal vaporization device. The chemical vapor infiltration device contains a preform containing ceramic fibers. The preform is infiltrated with a metallic coating or a coating of a metallic precursor along with a ceramic precursor coating. The metallic coating and/or the metallic precursor coating and the ceramic precursor coating are applied sequentially or simultaneously.

Abstract: An article includes a substrate and a barrier layer on the substrate. The barrier layer includes a matrix, diffusive particles dispersed in the matrix, and gettering particles dispersed in the matrix. The gettering particles include at least one alloyed metal silicide. A composite material and a method of fabricating an article are also disclosed.

Abstract: Disclosed is a coated ceramic fiber including a silicon carbide coating layer adjacent to the ceramic fiber and a silicon dioxide coating layer adjacent to the silicon carbide coating layer, wherein the silicon dioxide coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Abstract: Disclosed is a coated ceramic fiber including a zirconium interface coating layer deposited on the ceramic fiber, a zirconium dioxide interface coating layer adjacent to the zirconium interface coating layer, and an additional interface coating layer adjacent to the zirconium dioxide interface coating layer, wherein zirconium dioxide interface coating layer forms micro cracks after a crystal structure transformation. The coated ceramic fiber may be included in a composite material having a ceramic matrix.

Abstract: A method for fabricating a component according to an example of the present disclosure includes the steps of depositing a stoichiometric precursor layer onto a preform, and densifying the preform by depositing a matrix material onto the stoichiometric precursor layer. An alternate method and a component are also disclosed.