COMPOSITE COMPONENTS AND METHODS OF REDEFINING OPENINGS IN COMPOSITE COMPONENTS

A method of redefining an opening in a composite component comprises filling the opening with a filling material, where the opening is defined in a body of the composite component and opens onto a surface defined by the composite component, and redefining the opening such that the opening extends into the body. Some methods comprise removing an existing coating from the surface of the composite component prior to filling the opening with the filling material and applying a new coating to the surface prior to redefining the opening such that the opening extends through the new coating and into the body. An exemplary composite component comprises a body, a surface with a coating thereon, an original opening defined through the body and filled with a filling material, and a new opening defined through the coating into the body, which may be defined at a new location from the original opening.

FIELD

The present subject matter relates generally to composite components. More particularly, the present subject matter relates to methods of redefining openings in composite components.

BACKGROUND

Reinforced ceramic matrix composites (“CMCs”) comprising fibers dispersed in continuous ceramic matrices of the same or a different composition are well suited for structural applications because of their toughness, thermal resistance, high-temperature strength, and chemical stability. Such composites typically have high strength-to-weight ratio that renders them attractive in applications in which weight is a concern, such as in aeronautic applications. Their stability at high temperatures renders CMCs very suitable in applications in which components are in contact with a high-temperature gas, such as in a gas turbine engine.

CMCs can have additional surface coatings to protect the composite when used in high temperature, corrosive, and/or other harsh environments. Further, one or more holes or openings may be defined in a CMC, which can present a challenge for repairing a surface coating and/or the underlying CMC. For example, the holes or openings may be kept open during the repair or may be plugged and re-opened after the repair, either of which can be difficult. For example, the exact original location of holes or openings that are plugged during the repair must be found to re-open the holes or openings after the repair. Similar repair challenges can exist for other composites. Accordingly, improved methods for repairing CMCs and other composites would be desirable.

DETAILED DESCRIPTION

The terms “redefine,” “redefining,” and the like refer to removing material from a component to define a hole, aperture, or other opening in the component, such as through machining (e.g., drilling, electric discharge machining, etc.) or other means for material removal.

Generally, the present subject matter provides methods for redefining openings in composite components. For instance, the present subject matter provides a method of redefining openings in a composite component where openings in the composite component are filled with a material, such as a matrix material, after a surface coating is removed. The composite component is re-coated with a new surface coating, and the openings are redefined in the composite component. The opening filler or matrix material is well-matched to one or more properties of the material of the composite component such that the openings redefined in the composite component do not have to be defined in the exact same location as the original openings. For example, the redefined openings can be defined within a range of distances relative to the respective locations of the original openings. Additionally, or alternatively, the redefined openings can have a different size, shape, and/or pattern relative to the original openings.

Referring now to the drawings, wherein identical numerals indicate the same elements throughout the figures,FIG.1is a schematic cross-sectional view of a gas turbine engine in accordance with an embodiment of the present disclosure. More particularly, for the embodiment ofFIG.1, the gas turbine engine is a high-bypass turbofan jet engine10, referred to herein as “turbofan engine10.” As shown inFIG.1, the turbofan engine10defines an axial direction A (extending parallel to a longitudinal centerline12provided for reference) and a radial direction R. In general, the turbofan engine10includes a fan section14and a core turbine engine16disposed downstream from the fan section14.

For the depicted embodiment, fan section14includes a fan38having a plurality of fan blades40coupled to a disk42in a spaced apart manner. As depicted, fan blades40extend outward from disk42generally along the radial direction R. The fan blades40and disk42are together rotatable about the longitudinal centerline12by LP shaft36. In some embodiments, a power gear box having a plurality of gears may be included for stepping down the rotational speed of the LP shaft36to a more efficient rotational fan speed.

In some embodiments, components of the turbofan engine10may comprise a composite material, such as a ceramic matrix composite (CMC) material, which has high temperature capability. Composite materials generally comprise a fibrous reinforcement material embedded in matrix material, e.g., a ceramic matrix material. The reinforcement material serves as a load-bearing constituent of the composite material, while the matrix of a composite material serves to bind the fibers together and act as the medium by which an externally applied stress is transmitted and distributed to the fibers.

Exemplary CMC materials may include silicon carbide (SiC), silicon, silica, carbon, or alumina matrix materials and combinations thereof. Ceramic fibers may be embedded within the matrix, such as oxidation stable reinforcing fibers including monofilaments like sapphire and silicon carbide (e.g., Textron's SCS-6), as well as rovings and yarn including silicon carbide (e.g., Nippon Carbon's NICALON®, Ube Industries' TYRANNO®, and Dow Corning's SYLRAIVIIC®), alumina silicates (e.g., 3M's Nextel 440 and 480), and chopped whiskers and fibers (e.g., 3M's Nextel 440 and SAFFIL®), and optionally ceramic particles (e.g., oxides of Si, Al, Zr, Y, and combinations thereof) and inorganic fillers (e.g., pyrophyllite, wollastonite, mica, talc, kyanite, and montmorillonite). For example, in certain embodiments, bundles of the fibers, which may include a ceramic refractory material coating, are formed as a reinforced tape, such as a unidirectional reinforced tape. A plurality of the tapes may be laid up together (e.g., as plies) to form a preform component. The bundles of fibers may be impregnated with a slurry composition prior to forming the preform (e.g., prepreg plies) or after formation of the preform. The preform may then undergo thermal processing, such as a cure or burn-out to yield a high char residue in the preform, and subsequent chemical processing, such as melt-infiltration with silicon, to arrive at a component formed of a CMC material having a desired chemical composition. In other embodiments, the CMC material may be formed as, e.g., a carbon fiber cloth rather than as a tape.

Turning toFIG.2A, a composite component100of a gas turbine engine, such as turbofan engine10, will be described according to an embodiment of the present subject matter. As schematically illustrated inFIG.2A, the composite component100may be a composite airfoil such as a turbine stator nozzle airfoil. In other embodiments, the composite component100may be another composite airfoil, such as an inlet guide vane (IGV), an outlet guide vane (OGV)52, a rotor blade, etc. or other composite component such as a combustor liner, a fan case, a shroud, a turbine nozzle inner band or outer band, a frame (e.g., a turbine center frame or the like), etc.

The composite component100shown inFIG.2Aincludes a body102defining a surface104, with an existing coating106disposed on the surface104. A plurality of apertures, holes, or openings108are defined through the existing coating106into the body102. The plurality of openings108may be cooling holes, openings for instrumentation such as one or more sensors, openings for attachment features, channels, cavities, or the like or combinations thereof. For example, the plurality of openings108may be defined in the composite component100as cooling holes that allow a cooling fluid to flow from a cavity105defined within the composite component100, through the body102and the existing coating106to cool the composite component100, e.g., as the cooling fluid flows through the composite component100and/or as the cooling fluid flows over a surface110defined by the existing coating106. However, it will be appreciated that one or more of the openings108need not go all the way through the composite component100, e.g., from the surface110to the cavity105; that is, one or more openings108of the plurality of openings108may or may not be defined through the composite component100to the cavity105.

As shown inFIG.2A, each opening108has an opening length l. The opening length l may be the same for each opening108or may vary among the plurality of openings108, e.g., one opening108may define a shorter path between the cavity105and the surface110than another opening108. As further illustrated inFIG.2A, one or more openings108of the plurality of openings108may be defined at a substantially orthogonal angle with respect to the body surface104, i.e., the opening length l may extend at a substantially orthogonal angle with respect to surface104. Additionally, or alternatively, one or more of the openings108may have an opening length l extending at one or more non-zero and non-orthogonal angles, respectively, to the body surface104. For example, as shown inFIG.2B, a portion of the plurality of openings108have an opening length l extending at a non-zero and non-orthogonal angle α with respect to the surface104, while the remainder of the openings108have an opening length l extending substantially orthogonal or perpendicular to the surface104.

Additionally, or alternatively, one or more of the openings108may have a non-constant cross-sectional area and/or one or more of the openings108may have a non-round cross-sectional shape. For example, referring toFIG.2C, the openings108depicted that are defined from the surface110to the cavity105taper from a larger cross-sectional area at the surface110to a smaller cross-sectional area at the cavity105, e.g., the openings108defined through the composite component100to the cavity105have a larger width woat the surface110than at the cavity105. Further, the two openings108defined approximately in the middle of the illustrated portion of the composite component100are non-line of sight openings108, which comprise a change in direction from an end108bat the cavity105to an end108aat the surface110such that the end108bof the opening108at the cavity105is not along a line of sight to the end108aof the opening108at the surface110. Moreover,FIG.2Cdepicts an opening108on the right that has a non-round cross-section and that does not extend through the composite component100to the cavity105, e.g., the rightmost opening108may be an opening for an attachment feature or the like.

Over time, e.g., after a certain period of use or after an event in which the turbofan engine10and/or the composite component100is damaged, the existing coating106may need to be replaced. For instance, the existing coating106may sustain chipping, cracking, abrasion, erosion, recession, or other degradation, illustrated as degraded areas112inFIG.2A, that could hinder the performance or usefulness of the existing coating106.

In at least some embodiments, the existing coating106may be an environmental barrier coating (EBC), which can help protect the composite component body102from the harsh environment of, e.g., high temperature engine sections. For example, EBCs can provide a seal against the corrosive gases in the hot combustion environment, which can oxidize silicon-containing CMCs and monolithic ceramics, and EBCs can help prevent dimensional changes in the CMC component due to oxidation and volatilization of silicon oxide in high temperature steam, where silicon oxide can be converted to volatile (gaseous) silicon hydroxide species. Thus, when the EBC sustains chipping, cracking, abrasion, erosion, recession, etc., the EBC may need to be removed and reapplied to continue realizing the benefits of the EBC.

Referring now toFIGS.3through7, various methods of repairing a composite component100, e.g., by replacing the existing coating106with a new coating, are described. For example,FIGS.3through6provide schematic illustrations of various points in a method700of repairing a composite component100.FIG.7provides a flow diagram of the method700.

As shown inFIG.7, the method700includes (702) removing an existing coating106from a surface104of the composite component100. As previously described, the existing coating106may become degraded such that the performance or benefits of the coating are diminished or non-existent, and to restore the benefits provided by the coating, it is removed and replaced. In some embodiments, the existing coating106may be stripped from the composite component100by any suitable chemical or physical process, such as milling or the like. Referring toFIG.3, removing the existing coating106from the composite component100exposes the surface104of the composite component100defined by the body102.

After the existing coating106is removed, the method700includes (704) filling the plurality of openings108with a filling material114, as shown inFIG.4. For example, the composite component100may be a CMC component comprising a ceramic reinforcement material116, such as fibers or particles, disposed in a component matrix material118as schematically shown inFIG.2D. The filling material114may be a ceramic matrix material comprising a liquid carrier, a filler dispersed within the carrier, and a polymeric binder disposed in the carrier. The liquid carrier may be selected such that it partially or fully dissolves one or more organic components of the formulation, such as the binder. The filler may be fibers and/or a powder and may comprise at least one of silicon, silicon carbide, and carbon. The polymeric binder may be used to alter the flow properties of the filling material114, such as by thickening the filling material114to allow it to remain in place when applied to the composite component100as described herein. Optionally, the filling material114further comprises other ingredients disposed in the carrier, such as a shrinkage control agent, which provides a measure of rigidity to the formulation as it is processed. For example, the mass loss associated with volatilizing the liquid carrier and converting the binder to char creates a driving force to shrink the size of the remaining material, and excessive shrinkage can lead to undesirable cracking within the product material. Including a shrinkage control agent such as short fibers can provide mechanical support to mitigate the tendency to shrink.

The filling material114(e.g., the liquid carrier, the ceramic filler, and/or the polymeric binder forming the filling material114) may be selected to have substantially similar thermodynamic, physical, and/or chemical properties to the component matrix material118, e.g., such that the thermodynamic, physical, and/or chemical properties of the filling material114are well-matched to the thermodynamic, physical, and/or chemical properties of the component matrix material118. For instance, the filling material114and the component matrix material118may have a substantially similar coefficient of thermal expansion, elastic modulus, thermal conductivity, oxidation resistance, material compatibility, and/or chemical composition. As one example, the filling material114and the component matrix material118may have a material compatibility that helps prevent an unfavorable or undesirable reaction between the filling material114and the component matrix material118. Because the thermodynamic, physical, and/or chemical properties are substantially similar or well-matched, the composite component100at the plurality of openings108is similar to the remainder of the composite component100, the openings108need not be defined at precisely their original location when the openings108are redefined in the composite component100after recoating the composite component100as described below.

ComparingFIGS.3and4,FIG.4illustrates the filling material114disposed over the composite component surface104and within the plurality of openings108. The filling material114may be a paste, slurry, or other consistency for dispersing within the plurality of openings108. For instance, a filling material114slurry may be formed by mixing a liquid carrier with a ceramic filler and a polymeric binder and, optionally, other ingredients such as, e.g., a shrinkage control agent, etc. It will be appreciated that the filling material114need not completely fill each opening108, i.e., one or more of the openings108may be partially filled with the filling material114along the length l of the opening108. For example, when the filling material114is received in the one or more openings108, a small depression may be left near the composite component surface104, e.g., to help locate the openings108when redefining the openings108as described herein. As another example, one or more openings108may not be filled near the end of the respective opening108opposite the composite component surface104, e.g., at or near end108billustrated inFIG.2C.

In some embodiments, filling the plurality of openings108with the filling material114comprises injecting the filling material114into the plurality of openings108. As schematically shown inFIG.4A, the filling material114may be injected manually, e.g., by a human operator120manipulating an injection tool122by hand or otherwise to inject the filling material114into the openings108(FIG.3), or the filling material114may be injected automatically, e.g., by a robot or other automated machine124using an injection tool122to inject the filling material114into the openings108. It will be appreciated that the filling material114may be injected into each opening108individually or simultaneously into a plurality of openings108.

In other embodiments, filling the plurality of openings108with the filling material114comprises applying the filling material114to the surface104and over the plurality of openings108. For example, referring toFIG.4B, an application tool126, such as a putty knife or other straight-edge or similar tool, may be used by a human operator120to manually apply the filling material114over the surface104, including over the plurality of openings108(FIG.3). As another example, a robot or other automated machine124may automatically apply the filling material114over the surface104, including over the plurality of openings108, using the application tool126, e.g., a putty knife or other straight-edge or similar tool. In yet other embodiments, rather than or in addition to applying the filling material to the outer surface104and over the openings108, the filling material114may be applied to an inner surface, such as the inner surface of the composite component100defining the cavity105, and over the plurality of openings108.

In still further embodiments, filling the plurality of openings108with the filling material114comprises applying the filling material114to the surface104, and/or to an inner surface of the composite component100, and subjecting the composite component100to an elevated pressure. For instance, referring toFIG.4C, after the filling material114is applied over the surface104, including over one or more of the openings108(FIG.3), using the application tool126or another suitable tool, the composite component100is disposed in an autoclave or other chamber128. Then, the pressure within the chamber128is raised above ambient pressure to force the filling material114on the surface104into the plurality of openings108.

In yet other embodiments, filling the plurality of openings108with the filling material114comprises applying the filling material114to the surface104(and/or to an inner surface of the composite component100), placing the composite component100within an enclosure, and creating a pressure differential between an interior of the enclosure and an exterior of the enclosure. For example, referring toFIG.4D, after the filling material114is applied over the surface104, including over one or more of the openings108, using the application tool126or another suitable tool (e.g., as described with respect toFIGS.4A and4B), the composite component100is disposed in a bag130and sealed within the bag130. As such, the composite component100with the filling material114is placed within an enclosure, i.e., the bag130. In some embodiments, a vacuum line is connected to the bag130such that a vacuum may be drawn on the bag130with the composite component100therein, which lowers the pressure in the bag130relative to atmospheric pressure outside the bag130. The pressure differential between an interior132of the bag130and an exterior133of the bag130causes the bag130to push against the composite component100and force the filling material114into the openings108. In further embodiments, the composite component100, disposed in the bag130, may be placed in a chamber128, such as an autoclave or other pressure vessel, and the pressure raised above atmospheric pressure within the chamber128to force the filling material114on the surface104(and/or the inner surface of the composite component100) into the plurality of openings108. The bagged composite component100may be subjected to the elevated pressure within the chamber128with or without a vacuum being pulled on the bag130. It will be appreciated that, if a vacuum is pulled on the bag130, thereby lowering the pressure in the interior132of the bag130below atmospheric pressure, and the bag130is disposed in the chamber128and the pressure within the chamber128raised above atmospheric pressure, the pressure differential between the interior132of the bag130and the exterior133of the bag130will be greater than only pulling a vacuum on the bagged composite component100. In at least some embodiments, the greater compaction pressure provided by the larger pressure differential can help force the filling material114into the openings108compared to vacuum bagging alone.

As shown inFIG.7, the method700further may include (706) repairing the body102of the composite component100. As previously discussed with reference toFIG.2B, the composite component100may sustain damage, which can produce degraded areas112in the existing coating106and can also damage the body102of the composite component100. Accordingly, the body102may be repaired, e.g., by scarfing or otherwise cleaning out the damaged area(s) and replacing the damaged composite material with new layers of ceramic reinforcement material116(e.g., new fibers, etc.), new component matrix material118, new composite plies, etc., along with replacing the damaged existing coating106. It will be appreciated that repairing the body102need not occur after filling the one or more openings108with the filling material114as shown inFIG.7but, instead, may occur at any appropriate point in the method700. For instance, in some embodiments, repairing the body102may occur after removing the existing coating106but prior to filling the one or more openings108with the filling material114.

Keeping withFIG.7, after the one or more openings108are filled with the filling material114, the method700includes (708) processing the composite component100having the filled openings108. For instance, the composite component100may undergo burnout (or firing) and densification, e.g., the composite component100may be heated (fired) in a vacuum or inert atmosphere to decompose any binders and remove any solvents in the filling material114and convert the filling material114to the desired ceramic matrix material. Due to decomposition of the binders during burnout, the filling material114is porous, and the body102of the composite component100, particularly any areas that may have received new ceramic reinforcement material116and/or ceramic matrix material118, also may have pores or voids therein. Accordingly, the composite component100may undergo densification, e.g., melt infiltration (MI), chemical vapor infiltration (CVI), or polymer infiltration and pyrolysis (PIP), to fill the porosity and yield a densified CMC component100. Specific processing techniques and parameters for the above process will depend on the particular composition of the materials. For example, silicon carbide CMC components may be infiltrated with molten silicon, e.g., through a silicon MI process or a reactive MI process. Other densification techniques include, but are not limited to, PIP processes (e.g., where silicon carbide reinforcement material components are infiltrated with a preceramic polymer, such as polysilazane and then heat treated to form a SiC matrix), oxide/oxide processes (e.g., for aluminum or alumino-silicate reinforcement material components), and CVI processes (e.g., for carbon fiber reinforced silicon carbide matrix (C/SiC) CMCs, for SiC/SiC CMCs, etc.).

As further shown inFIG.7, the method700includes (710) applying a new coating134to the surface104. As shown inFIG.5, the new coating134is applied over the surface104and the openings108filled with the filling material114. The new coating134may be, e.g., a new EBC or other surface coating, and may be applied using any suitable application method. For instance, the new coating134may be applied as a thermal spray, such as an air plasma spray, or a slurry coating, e.g., using a dip and spin application technique.

Referring still toFIG.7, the method700includes (712) redefining at least one opening108of the plurality of openings108such that a new, redefined opening108′ extends through the new coating134and into the body102of the composite component100, as shown inFIG.6. The opening(s)108may be redefined as new opening(s)108′, e.g., by drilling, electric discharge machining (EDM), laser drilling, or any suitable means for defining a hole, aperture, or other opening in the composite component100.

It will be appreciated that the redefined opening(s)108′ may be referred to as new opening(s)108′ because the original plurality of openings108were filled with the filling material114such that the new opening(s)108′ need not be redefined in precisely the same location, orientation, size, shape, number, and/or pattern as the original openings108. For example, referring back toFIG.2A, each existing or original opening108of the plurality of openings108has an original width woand is defined at an original location136in the body102of the composite component100, prior to filling the existing or original opening108with the filling material114as described herein. The original width womay be within a range of about 6 mils to about 160 mils, such as within a range of about 40 mils to about 120 mils and such as within a range of about 60 mils to about 100 mils. For example, the low end of the range of original width womay be about the thickness of a single CMC ply. As described herein, e.g., with respect toFIG.2C, the original width woof each opening108may vary along the length l of the original opening108, or the cross-sectional area of the original opening108may vary along its length l.

In at least some embodiments, redefining the opening108in the body102comprises redefining the opening108(as a new opening108′) at a new location138that may be, e.g., within one-half the original width wo(½ wo) of the original location136. For instance, inFIG.6, an original opening108is shown in phantom or dashed lines, with a new opening108′ shown in solid lines. As indicated, the difference in location between the new opening108′ and the original opening108is up to one-half the original width wo. For example, for an original opening108having an original width woof 100 mils and defined at an original location136, the redefined or new opening108′ is defined at a new location138within 50 mils of the original location136. In at least some embodiments, the new opening(s)108′ are defined at the respective original location136of each opening108.

Further, a new opening108′ may be defined in the same orientation as the respective original opening108, e.g., the new opening108′ may be defined at the same angle to the surface104as the respective original opening108. Additionally, or alternatively, one or more new openings108′ may be defined at different orientations than the respective original opening108, e.g., one or more new openings108′ may be defined at a different angle to the surface104than the respective original opening108. As further examples, one or more new openings108′ may be defined with a different width or cross-sectional area as the respective original opening108and/or the new openings108′ may be defined in a different pattern in the composite component100compared to the original openings108. Further, the width or cross-sectional area of each new opening108′ may vary in the same manner or in a different manner as a respective original opening108.

Accordingly, as described herein, the present subject matter provides methods of redefining one or more openings in composite components and composite components having one or more redefined openings therein. For instance, the present subject matter provides for filling in openings of a composite component with a matrix material to provide a relatively pristine surface for re-coating the composite component in a repair process. That is, the matrix material fills openings defined in the composite component to restore a surface of the composite component to an uninterrupted state to accept a coating on the surface and then the openings are redefined in the composite component. The matrix material may have one or more properties that are substantially similar to the properties of the composite component material such that when the openings are redefined in the composite component, the alignment of the openings does not have to exactly match the original positions of the openings. Other advantages of the subject matter described herein also may be realized by those of ordinary skill in the art.

A method comprising filling an opening with a filling material, the opening defined in a body of a composite component and opening onto a surface defined by the composite component; and redefining the opening such that the opening extends into the body, wherein the composite component is a ceramic matrix composite component comprising ceramic reinforcement material disposed in a component matrix material.

The method of any preceding clause, further comprising applying a coating to the surface after filling the opening with the filling material.

The method of any preceding clause, further comprising removing an existing coating from the surface of the composite component prior to filling the opening with the filling material.

The method of any preceding clause, further comprising adding ceramic reinforcement material, component matrix material, or both in the body of the composite component.

The method of any preceding clause, wherein the opening is defined at an original location in the body prior to filling the opening with the filling material, and wherein redefining the opening comprises redefining the opening at a new location.

The method of any preceding clause, wherein the opening has an original width, and wherein the new location is within one-half the original width of the original location.

The method of any preceding clause, wherein filling the opening with the filling material comprises injecting the filling material into the opening.

The method of any preceding clause, wherein filling the opening with the filling material comprises applying the filling material to the surface and over the opening.

The method of any preceding clause, wherein filling the opening with the filling material comprises applying the filling material to the surface, placing the composite component with the filling material applied thereto within an enclosure, and creating a pressure differential between an interior of the enclosure and an exterior of the enclosure.

The method of any preceding clause, wherein the enclosure is a bag.

The method of any preceding clause, wherein the enclosure is a bag, and wherein creating the pressure differential between the interior of the enclosure and the exterior of the enclosure comprises drawing a vacuum on the bag.

The method of any preceding clause, wherein the enclosure is a bag, and further comprising disposing within a chamber the composite component with the filling material applied thereto that is placed within the bag.

The method of any preceding clause, wherein creating the pressure differential between the interior of the enclosure and the exterior of the enclosure comprises raising the pressure within the chamber.

The method of any preceding clause, wherein the filling material has substantially similar thermodynamic, physical, and chemical properties to the component matrix material, and wherein the substantially similar thermodynamic, physical, and chemical properties are at least one of coefficient of thermal expansion, elastic modulus, thermal conductivity, oxidation resistance, material compatibility, and chemical composition.

The method of any preceding clause, wherein the opening has a length extending substantially orthogonal to the surface.

The method of any preceding clause, wherein the opening has a length extending at a non-zero and non-orthogonal angle to the surface.

The method of any preceding clause, wherein the opening has a width within a range of about 6 mils to about 160 mils.

The method of any preceding clause, wherein the opening has a width within a range of about 40 mils to about 120 mils.

The method of any preceding clause, wherein the opening has a width within a range of about 60 mils to about 100 mils.

The method of any preceding clause, wherein the composite component is an airfoil, shroud, combustor liner, turbine nozzle band, or frame and the opening is a cooling hole.

The method of any preceding clause, wherein the existing coating is an environmental barrier coating.

The method of any preceding clause, wherein the opening filled with the filling material is an original opening and the redefined opening is a new opening, and wherein the new opening is defined at a different location than the original opening.

The method of any preceding clause, wherein the original opening is a plurality of original openings and the new opening is a plurality of new openings, and wherein the plurality of new openings are defined in a different pattern than the plurality of original openings.

The method of any preceding clause, wherein the original opening is a plurality of original openings and the new opening is a plurality of new openings, and wherein at least one new opening of the plurality of new openings has different dimensions from an original opening of the plurality of original openings.

The method of any preceding clause, wherein the original opening is a plurality of original openings and the new opening is a plurality of new openings, and wherein at least one new opening of the plurality of new openings has a different cross-sectional shape from an original opening of the plurality of original openings.

The method of any preceding clause, wherein the original opening is a plurality of original openings and the new opening is a plurality of new openings, and wherein the plurality of new openings is different in number from the plurality of original openings.

A method comprising removing an existing coating from a surface of a ceramic matrix composite component; filling an opening with a filling material, the opening defined in a body of the ceramic matrix composite component and opening onto the surface; applying a new coating to the surface; and redefining the opening such that the opening extends through the new coating and into the body.

The method of any preceding clause, wherein the filling material comprises a liquid carrier, a filler dispersed within the liquid carrier, and a polymeric binder disposed in the liquid carrier.

The method of any preceding clause, wherein the filler comprises at least one of silicon, silicon carbide, and carbon.

The method of any preceding clause, wherein the opening has a width within a range of about 6 mils to about 160 mils.

The method of any preceding clause, wherein the opening has a width within a range of about 40 mils to about 120 mils.

The method of any preceding clause, wherein the opening has a width within a range of about 60 mils to about 100 mils.

The method of any preceding clause, wherein the opening is defined at an original location in the body prior to filling the opening with the filling material, and wherein redefining the opening comprises redefining the opening within one-half the width of the original location.

A composite component comprising a ceramic matrix composite body having a surface; a coating on the surface; an original opening defined through the body, the original opening filled with a filling material; and a new opening defined through the coating into the body, wherein the original opening is defined at an original location in the body, and wherein the new opening is defined at a new location.

The composite component of any preceding clause, wherein the original opening has an original width, and wherein the new location is within one-half the original width of the original location.