Method of coating a gas turbine engine component

Abstract

Methods and apparatuses for coating a gas turbine engine component are provided. For example, a method can include plugging a plurality of openings defined in a surface of a gas turbine engine component with a reusable filler material, applying an anchor source to the reusable filler material to retain the reusable filler material in the plurality of openings, applying a coating to the surface of the gas turbine engine component, removing the reusable filler material from the plurality of openings, and collecting the reusable filler material. The filler material can have various shapes for plugging the plurality of openings and can be formed from various materials.

Description

Technical Field

[0001] This topic generally relates to methods for coating components (such as gas turbine engine components) so that openings in the components are not blocked by the coating. Background Technology

[0002] Components used in high-temperature, corrosive, or other harsh environments, such as gas turbine engines, typically have protective coatings applied to their surfaces. These components often have orifices or openings that should not be covered or obstructed by the coating, posing challenges during the initial application and subsequent repair of the coating. Keeping these orifices or openings open during treatment, or sealing and reopening them after treatment, can be difficult. For example, the exact original location of an orifice or opening that was sealed during treatment must be located in order to reopen it later. Gas turbine engine components may have numerous orifices or openings, such as cooling vents defined in their outer surfaces. This complicates the reopening process and requires significant amounts of sealing material. Attached Figure Description

[0003] The specification with reference to the accompanying drawings sets forth a complete and feasible disclosure for those skilled in the art, including its best mode, wherein:

[0004] Figure 1A A schematic side view of a portion of a component having a plurality of openings defined in the outer surface of the component, according to an exemplary aspect of this subject matter, is provided.

[0005] Figure 1B A schematic cross-sectional view of the component is provided.

[0006] Figure 2 A flowchart illustrating a method for coating components according to an exemplary aspect of this subject is provided.

[0007] Figure 3 Provided with the original coating on the outer surface Figure 1B A schematic cross-sectional view of the component.

[0008] Figure 4A The original coating is removed and a reusable filler material is provided in multiple openings. Figure 3 A schematic cross-sectional view of the component.

[0009] Figure 4B , Figure 4C , Figure 4D , Figure 4E and Figure 4F Various embodiments are provided where the original coating is removed and reusable filler material and anchoring source are available. Figure 3 A schematic cross-sectional view of a part of the component.

[0010] Figure 5A It provides a source for anchoring magnets that has been removed from its original coating and has reusable filler material for magnetic rods disposed in multiple openings, and for raising the magnetic rods in the openings. Figure 3 A schematic cross-sectional view of a part of the component.

[0011] Figure 5B It provides a magnetic rod with reusable filler material in which the original coating is removed and the openings are arranged in multiple openings, and a magnetic anchoring source for abutting the magnetic rod against a component. Figure 3 A schematic cross-sectional view of a part of the component.

[0012] Figure 6 Provides a reusable filler material disposed in multiple openings during the coating process. Figure 4A A schematic cross-sectional view of the component.

[0013] Figure 7 Provided during the heat treatment process Figure 6 A schematic cross-sectional view of the coated component.

[0014] Figure 8 A schematic cross-sectional view of the coated component is provided during the removal and collection of reusable filler material for use in a second component.

[0015] Figure 9 A schematic cross-sectional view of a second component having a plurality of openings defined in its outer surface is provided, wherein reusable filler material is disposed in the plurality of openings. Detailed Implementation

[0016] Reference will now be made in detail to the present embodiments of this disclosure, one or more examples of which are illustrated in the accompanying drawings. The detailed description uses numerals and letter reference numerals to denote features in the drawings. Similar or analogous reference numerals in the drawings and description have been used to denote similar or analogous portions of this disclosure.

[0017] The term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any implementation described herein as "exemplary" is not necessarily to be construed as superior or better than other implementations. Furthermore, unless explicitly stated otherwise, all embodiments described herein should be considered exemplary.

[0018] Unless the context clearly indicates otherwise, the singular forms “a,” “a,” and “the” include plural references.

[0019] In a context such as “at least one of A, B and C”, the term “at least one” means only A, only B, only C, or any combination of A, B and C.

[0020] As used herein, the terms “first,” “second,” “third,” and other serial numbers are used to distinguish one component from another and are not intended to indicate the location or importance of individual components.

[0021] Unless otherwise stated herein, the terms “connection,” “fixed,” “attached to,” etc., refer to both direct connection, fixation, or attachment, and indirect connection, fixation, or attachment via one or more intermediate components or features.

[0022] The terms “redefinition”, “re-defined”, etc., refer to the removal of material from a part by means of machining (e.g., drilling, electrical discharge machining, etc.) or other means of material removal to define a hole, orifice or other opening in the part.

[0023] As used throughout this specification and claims, approximate language is applied to modify any quantitative expression that may allow for variation without altering its underlying function. Therefore, values ​​modified by one or more terms such as “about,” “approximate,” and “substantially” are not limited to specified exact values. In at least some cases, approximate language may correspond to the precision of the instrument used to measure the value, or the precision of the method or machine used to construct or manufacture the component and / or system. Approximate language may refer to a margin of + / -1%, 2%, 4%, 10%, 15%, or 20% at the endpoints of a single value, a range of values, and / or a defined range of values.

[0024] Throughout this specification and claims, scope limitations are combined and interchanged, and unless the context or language otherwise indicates otherwise, such scopes are identified and include all subscopes contained herein. For example, all scopes disclosed herein include endpoints, and endpoints may be combined independently of each other.

[0025] Generally, this subject matter provides methods for coating the surface of a component without obstructing one or more openings defined in the surface by a coating. More specifically, the inventors of this disclosure seek simple and cost-effective methods to prevent coatings from penetrating one or more openings, such as cooling holes or other channels defined in the surface of a gas turbine engine component. For example, aero-engine components (such as blades or nozzles) typically contain hundreds of cooling holes that must remain open and maintain their geometry to function as designed. Coating or recoating these components can be a challenging task because the process requires preventing coatings from penetrating a large number of cooling holes, or involves reopening the cooling holes. For example, reopening or redefining cooling holes may require complex drilling and / or laser alignment with existing cooling holes, and / or the large number of cooling holes on a single component may present challenges in terms of time, equipment, etc., for reopening or redefining these openings after repair or coating. Furthermore, sealing a large number of cooling holes with plugs or other materials (e.g., disposable plugs or disposable filler materials) used only once on a single component can be time-consuming and expensive.

[0026] The inventors of this disclosure recognized that sealing openings defined in the surface of a component with a reusable material avoids the complexity of redefining or reopening these openings and reduces the costs associated with preventing coatings from entering the openings. The inventors have discovered methods for sealing multiple openings in a component that are easy to perform and utilize reusable materials, providing time and cost savings.

[0027] Referring now to the accompanying drawings, where the same number represents the same element throughout the drawings. Figure 1A This is a schematic diagram of a part of component 100, and Figure 1B This is a schematic cross-sectional view of component 100. Component 100 may be an airfoil of a gas turbine engine (e.g., a turbofan jet engine), such as a turbine stator nozzle airfoil. In other embodiments, component 100 may be another airfoil (such as an inlet guide vane (IGV), an outlet guide vane (OGV), a rotor blade, etc.), or another gas turbine engine component (such as a combustor bushing, fan housing, shroud, turbine nozzle inner or outer band, frame (e.g., turbine center frame, etc.)). In other embodiments, component 100 may be a component of an assembly other than a gas turbine engine.

[0028] Component 100 can be formed from any suitable material. For example, gas turbine engine components are typically formed from metallic materials (such as superalloys) or composite materials (such as ceramic matrix composites (CMC) or polymer matrix composites (PMC)). In various embodiments, component 100 is formed from metallic materials or composite materials.

[0029] like Figure 1A As shown, component 100 includes a body 102 and a plurality of openings 104 defined in an outer body surface 106 of the body 102. The plurality of openings 104 may be cooling holes, channels, cavities, openings for instruments (such as one or more sensors), openings for attachment features, or any combination of such openings or orifices. For example, a first portion of the plurality of openings 104 may be a cooling hole, a second portion of the plurality of openings 104 may be an opening for an instrument (e.g., an inlet port), and a third portion of the plurality of openings 104 may be an opening for an attachment feature.

[0030] refer to Figure 1B In some embodiments, at least a portion of the plurality of openings 104 extends from the outer body surface 106 to the inner cavity 108. For example, at least a portion of the plurality of openings 104 may be defined in the component 100 as cooling holes, such as those allowing cooling fluid to flow between the inner cavity 108 defined within the body 102 and the outer body surface 106 (or the coating applied to the outer body surface 106 as described above) to cool the component 100 as cooling fluid flows through the component 100 and / or from the outermost surface of the component 100 (e.g., the outer body surface 106 or the surface defined by a coating applied to the outer body surface 106 as described above). However, it will be understood that one or more of the openings 104 do not need to completely penetrate the body 102, for example, from the outer body surface 106 to the inner cavity 108. That is, as Figure 1B As shown, some of the multiple openings 104 may be through holes defined to reach the internal cavity 108 through the component 100, while other openings 104 may be blind holes that do not reach the internal cavity 108.

[0031] and Figure 1B To maintain consistency, one or more of the plurality of openings 104 may be defined at substantially orthogonal angles relative to the outer body surface 106; for example, the opening length of the opening 104 may extend at substantially orthogonal angles relative to the outer body surface 106. Additionally or alternatively, one or more of the openings 104 may have opening lengths extending relative to the outer body surface 106 at one or more non-zero and non-orthogonal angles, respectively. For example, as... Figure 1B As shown, the two openings 104 defined on the right side of component 100 are non-line-of-sight openings 104, which include a directional change from a first end 104a at the outer body surface 106 to a second end 104b at the inner cavity 108, such that the corresponding second end 104b of the corresponding opening 104 at the inner cavity 108 is not within the line of sight to the first end 104a of the corresponding opening 104 at the outer body surface 106.

[0032] Additionally or alternatively, one or more of the openings 104 may have a non-constant cross-sectional area and / or one or more of the openings 104 may have a non-circular cross-sectional shape. For example, one or more of the plurality of openings 104 defined from the outer body surface 106 to the inner cavity 108 may gradually taper from a larger cross-sectional area at the surface 106 to a smaller cross-sectional area at the inner cavity 108. In such an embodiment, the width of the opening 104 defined to extend through the body 102 of the component 100 to the inner cavity 108 is greater at the outer body surface 106 than at the inner cavity 108. In other embodiments, the width of one or more openings 104 at the inner cavity 108 is greater than the width at the outer body surface 106. Furthermore, the plurality of openings 104 may have one or more suitable cross-sectional shapes, such as a circular or perfectly circular cross-section, a square cross-section, a rectangular cross-section, a hexagonal cross-section, etc.

[0033] During the initial fabrication of component 100, a coating may be applied to the outer body surface 106. In at least some embodiments, the plurality of openings 104 are defined such that the coating will not penetrate or seep into the openings 104 by means of this initial or original coating. Over time, such as after a period of use or after an event that damages component 100 (or another component in which component 100 is disposed). For example, the initial or original coating may suffer from peeling, cracking, abrasion, erosion, denting, or other degradation that may impair the performance or usefulness of the initial or original coating and / or component 100. In these embodiments, the initial or original coating may be reapplied to component 100 in which the plurality of openings 104 are defined. In other embodiments, instead of defining the plurality of openings 104 by the original coating, the original coating may be applied to component 100 in which the plurality of openings 104 are already defined. In either case, it is undesirable for the coating to penetrate or seep into the plurality of openings 104 so that the plurality of openings 104 can function as intended (as cooling holes, sensor receiving holes, etc.).

[0034] The coating can be one or more of a variety of coatings, such as a thermal barrier coating (TBC) or an environmental barrier coating (EBC), which can help protect the body 102 of component 100 from the harsh environment, such as that of a high-temperature gas turbine engine section. For example, an EBC can provide a seal against corrosive gases in the hot combustion environment of a gas turbine engine, which can oxidize silicon-containing ceramic matrix composites (CMCs) and monolithic ceramics. The EBC also helps prevent dimensional changes in CMC components due to the oxidation and volatilization of silica in high-temperature steam, where silica can be converted into volatile (gaseous) silicon hydroxide. EBCs can also benefit components made of other materials, such as superalloys. Therefore, when an EBC suffers from peeling, cracking, wear, erosion, denting, etc., it may be necessary to remove and reapply the EBC to continue to realize its benefits. The coating can be any of many other protective coatings and can be applied using any suitable process, such as a line-of-sight deposition process. A line-of-sight deposition process coats only surfaces directly visible from the source, where atoms or molecules move directly from the origin to the target with minimal scattering or deflection. Examples of line-of-sight processes include thermal spraying, room temperature spraying, physical vapor deposition (PVD), or sputtering. Exemplary thermal spraying processes include, but are not limited to, air plasma spraying (APS), very low pressure plasma spraying (VLPPS), suspension plasma spraying (SPS), high-velocity oxygen fuel (HVOF), solution precursor plasma spraying (SPPS), and high-velocity air fuel (HVAF). Exemplary physical vapor deposition processes include, but are not limited to, electron beam physical vapor deposition (EBPVD) and plasma spray physical vapor deposition (PSPVD). Exemplary sputtering techniques include, but are not limited to, magnetron sputtering, radio frequency (RF) sputtering, diode sputtering, and reactive sputtering. Other deposition processes, such as slurry-based processes or chemical vapor deposition (CVD) processes, can also be used to apply coatings.

[0035] Now for reference Figure 2 A flowchart of a method 200 according to an exemplary aspect of this disclosure is provided. Figure 2 Method 200 can be used to coat and / or recoat parts, such as gas turbine engine parts, as referenced above. Figure 1A and Figure 1B As stated above. Furthermore... Figure 3-9 The portions of method 200 are provided to illustrate this in sequence. Therefore, it will be understood that method 200 is generally used for coating and / or recoating the parts described herein. However, in other exemplary aspects, method 200 may be additionally or alternatively used for coating any other suitable parts. Additionally, although... Figure 2The steps are described in a specific order for illustrative and discussion purposes, but the methods discussed herein are not limited to any particular order or arrangement. Those skilled in the art will understand, using the disclosure provided herein, that the steps of the methods disclosed herein can be omitted, rearranged, combined, and / or adapted in various ways without departing from the scope of the subject matter.

[0036] As depicted, method 200 may optionally include removing the original coating at frame (202). For example, as described above and as... Figure 3 As shown, in some embodiments, an initial coating 110 is applied to the component 100 before defining the plurality of openings 104 within the body 102 of the component 100. For example, the initial coating 110 is applied to the outer body surface 106 of the body 102, and then the plurality of openings 104 are defined to enter the body 102 through the initial coating 110 and the outer body surface 106; at least some of the openings 104 may extend into the internal cavity 108 of the component 100, as described above regarding... Figure 1B As stated above.

[0037] As previously described, the original coating 110 may degrade, for example, the original coating 110 may suffer from peeling, cracking, abrasion, erosion, denting or other degradation, which reduces or completely eliminates the performance or benefits of the original coating 110, and / or reduces the performance of component 100. Figure 3 The degraded area 111 is shown. To restore the benefits provided by the coating, it is removed and replaced as described herein. In some embodiments, the initial or original coating 110 can be peeled off from the part 100 by any suitable chemical or physical process, such as polishing. Reference Figure 4A Removing the initial or original coating 110 from component 100 exposes the outer body surface 106 of component 100.

[0038] Therefore, as Figure 2 As shown in box (202), the original coating 110 can be removed to prepare for the application of a new coating. However, the new coating must not block or obstruct the multiple openings 104, as this could impair or hinder the performance of component 100, for example, by limiting or preventing the cooling flow through the multiple openings 104. Therefore, the multiple openings 104 can be blocked with filler during coating and then reopened after the new coating is applied to prevent the new coating from obstructing the openings 104.

[0039] The removal of the coating, as shown in box (202), is optional and can be omitted during the formation of a new or original part, or when applying the coating to an uncoated part. That is, it may not be necessary to remove the initial or original coating during method 200 to prevent the coating from obstructing openings in the part. In other words, the opening may be defined in the part before any coating is applied, and then blocked and reopened as described herein (i.e., the blockage is removed after coating) to ensure that the opening is open after coating application.

[0040] refer to Figure 2 At frame (204), method 200 includes sealing a plurality of openings defined in the surface of the component with a reusable filler material. Figures 4A-4F As schematically shown, reusable filler material 112 is used to seal a plurality of openings 104 defined in the outer body surface 106 of component 100. At least, reusable filler material 112 is a durable mask for the plurality of openings 104 that is removed in a non-destructive manner, but reusable filler material 112 can be formed from a variety of different materials as described in more detail below. In at least some embodiments, reusable filler material 112 can be reused after the coating process, simply by cleaning it between the coating process and reuse (e.g., in a subsequent coating process). That is, in at least some embodiments, reusable filler material 112 can be reused without reshaping, remolding, etc., except for removing coating material or adhesive anchoring material (e.g., by cleaning reusable filler material 112).

[0041] In some embodiments, the reusable filler material 112 is a plurality of blocks 112p of reusable filler, wherein one or more blocks 112p block each of a plurality of openings 104. Furthermore, in some embodiments, such as Figure 4A As shown, reusable filler material 112 extends beyond the plurality of openings 104 and the outer body surface 106 of component 100, such that after application, coating 116 ( Figure 6 , Figure 7 , Figure 8 There is a discontinuity at multiple openings 104, such as Figure 8 As shown. This discontinuity reduces or eliminates the need to remove the coating from above or around the opening 104 at the filler material 112 and / or the outer body surface 106.

[0042] The reusable filler material 112 can be formed of various materials and / or have various shapes. In some embodiments, the reusable filler material 112 is press-fitted or otherwise positioned in the opening 104 to hold the reusable filler material 112 in place. In other embodiments, an anchoring source 114 is used to anchor or hold the reusable filler material 112 in place. Thus, method 200 may optionally include applying an anchoring source to the reusable filler material at block (206) to hold the reusable filler material in a plurality of openings. For example, in some embodiments, the reusable filler material 112 is formed of a magnetic material (such as a ferromagnetic material), and the anchoring source 114 is a magnet, such as... Figure 4B and Figure 4C As shown. In another embodiment, such as Figure 4D As shown, the anchoring source 114 is a vacuum suction device used to apply suction through the open end opposite the filler material 112 and the coating. In yet another embodiment, such as Figure 4E As shown, anchoring source 114 is an adhesive material. In some embodiments, the adhesive material is a moldable clay material (such as polymeric clay or another similar moldable material), and in other embodiments, the adhesive material is a polymeric resin, such as an organic polymer, an inorganic polymer (such as geopolymer, sodium silicate, aluminum phosphate), a ceramic precursor polymer, a phenolic resin, or a furan or furfuryl alcohol resin. In embodiments where anchoring source 114 is an adhesive (such as moldable clay material, polymeric resin, putty, etc.), blocking the plurality of openings 104 may include applying adhesive material to each of the plurality of openings 104 and pressing reusable filler material 112 into the adhesive material. Alternatively, blocks 112p of reusable filler material 112 may be pressed into blocks of adhesive material, which in turn may be pressed into or applied to the respective openings 104 of the plurality of openings 104.

[0043] Furthermore, in some embodiments, the reusable filler material 112 may be formed of a relatively lightweight material for applying the desired anchoring source 114. For example, in the case where the anchoring source 114 is a vacuum suction device, the reusable filler material 112 may be formed of a relatively lightweight material (such as a polymer) to facilitate holding the reusable filler material 112 in place using the vacuum suction anchoring source 112 (e.g., without requiring excessively strong vacuum suction).

[0044] Therefore, it will be understood that the reusable filler material 112 is formed of a suitable material and / or has a suitable shape for holding the reusable filler material 112 in proper position within the plurality of openings 104 using the anchoring source 114. The shape of the reusable filler material 112 also simplifies the placement of the reusable filler material 112 in each of the plurality of openings 104. In some embodiments, plugging the plurality of openings with reusable filler material as shown at block (204) of method 200 includes at least one of agitate components or reusable filler material to self-assemble the reusable filler material within the plurality of openings.

[0045] More specifically, the reusable filler material can be multiple blocks, and sealing multiple openings includes placing the multiple blocks together with the component and agitating at least one of the multiple blocks or components such that the multiple blocks self-assemble in the multiple openings to seal the multiple openings with the reusable filler material. For example, the reusable filler material 112 can be multiple blocks 112p each having a spherical shape, i.e., each of the multiple blocks 112p of the reusable filler material is a ball or a spherical bead. In some embodiments, the multiple spherical blocks 112p are placed in a container together with the component 100, and the container is agitated (e.g., shaken or moved left and right and / or up and down) to agitate the multiple blocks 112p and the component 100, causing the multiple blocks 112p to roll into the multiple openings 104 defined in the component 100. The container may be agitated until each opening 104 has at least one block 112p of reusable filler material placed therein. Once rolled into place, the reusable filler material 112 (i.e., a plurality of spherical blocks 112p) will block the plurality of openings 104, wherein at least one block of the reusable filler material 112 is positioned in each of the plurality of openings 104.

[0046] The reusable filler material 112 can also self-assemble in the plurality of openings 104 in other ways. For example, applying a magnetic anchoring source 114 to the magnetic reusable filler material 112 can induce blocks of the reusable filler material 112 to self-assemble into the plurality of openings 104 defined in the component 100. As another example, a vacuum suction anchoring source 114 can induce blocks of the reusable filler material 112 to move into the plurality of openings 104, thereby self-assembling into the openings 104.

[0047] Furthermore, the anchoring source 114 can be manipulated to influence the orientation of the reusable filler material 112 within the plurality of openings 104. In some embodiments, the anchoring source 114 (which is a magnet) can be oriented or otherwise manipulated to orient the magnetic reusable filler material 112 relative to the plurality of openings 104 in a desired orientation. For example, the reusable filler material 112 can be a plurality of magnetic rods, the plurality of openings 104 can be a plurality of cooling holes, and the magnetic anchoring source 114 can be positioned adjacent to the component 100 to orient the plurality of magnetic rods, for example, to cover the entire throat region of the plurality of cooling holes or to cover the entire throat region smaller than the plurality of cooling holes. More specifically, refer to Figure 1A , Figure 5A and Figure 5B In some embodiments, one or more of the plurality of openings 104 (such as cooling holes) may have a throat region 115 at the outer body surface 106 of the component 100, the throat region 115 being wider than the remainder of the cooling holes extending into the body 102 of the component 100. Figure 5A As shown, the magnet anchoring source 114 can be used, for example, to erect the reusable filler material 112 (which is a plurality of magnetic rods) such that the reusable filler material 112 covers the width of the cooling hole extending into the body 102 (rather than the entire enlarged throat region 115). Alternatively, as Figure 5B As shown, the magnet anchoring source 114 can be used to place multiple magnetic rods against the component 100, such that reusable filler material 112 covers all or most of the enlarged throat region 115 (and also extends into the cooling holes to prevent coating from entering there).

[0048] The reusable filler material 112 may also have other shapes. In some embodiments, as described above, at least one of the plurality of blocks 112p of the reusable filler material 112 has a spherical shape, or a ball or spherical bead, and in other embodiments, at least one of the plurality of blocks 112p of the reusable filler material 112 is an elongated filament. For example, a block 112p of the reusable filler material 112 having an elongated filament shape may be a cylinder whose length is several times larger than its diameter, such that the block 112p is a relatively thin cylinder, thus resembling a filament. This filamentous reusable filler material 112 can be suitable for smaller openings 104, for example, for openings 104 having a relatively small diameter or cross-sectional area. Each block 112p of the reusable filler material 112, which is formed into long filaments, can extend into a corresponding opening 104 of a plurality of openings 104 in the component 100, in which the filament block 112p is disposed. For example, each filament block 112p can extend from the outer body surface 106 toward the inner cavity 108.

[0049] In some embodiments, one or more blocks 112p of reusable filler material 112 have a rod-like shape, for example, a cylindrical shape that is generally wider than a filament or has a larger diameter than a filament. Larger rod-shaped reusable filler material 112 can be used, for example, for openings 104 with a larger diameter, or for openings having a larger cross-sectional area than openings 104 in which filamentous reusable filler material 112 is used. That is, the size and / or shape of one or more blocks 112p of reusable filler material 112 can be selected based on the size and / or shape of the respective openings 104 in component 100, for example, to more effectively plug each corresponding opening 104.

[0050] Furthermore, in some embodiments, the filamentary or rod-shaped blocks 112p of the reusable filler material 112 may have shaped heads. That is, one end of the filamentary or rod-shaped block 112p may have a shape that anchors the block 112p in the corresponding opening 104, such as a sphere, teardrop, cone, etc. For example, as Figure 4C As shown, the filamentous block 112p can be bent, wrapped, or otherwise gathered at one end to have a generally teardrop-shaped head. The shaped head of the corresponding block 112p of the reusable filler material 112 can self-anchor the block 112p in the corresponding opening 104 and / or can work with an external anchoring source 114 to anchor the block 112p in the corresponding opening 104; the shaped head can also help to block the corresponding opening 104 to prevent coating material from entering.

[0051] In other embodiments, at least one of the plurality of blocks 112p of reusable filler material 112 has a shape complementary to the shape of at least one of the plurality of openings 104. (As mentioned above regarding...) Figure 1B Each opening 104 may have the same shape, or one or more openings 104 may have a shape different from the rest of the openings 104. For example, some openings 104 may extend in a generally linear manner with a constant cross-sectional shape, but other openings 104 may have a direction that varies along their length, and / or have variations in cross-sectional shape and / or width. In some embodiments, at least one block 112p of reusable infill material 112 is 3D printed to have a shape complementary to the shape of at least one of the multiple openings 104. By 3D printing the block 112p of reusable infill material 112, the reusable infill material 112 can conform to the opening 104 regardless of the shape, size, etc. of the opening 104 at all locations along the length of the opening 104. That is, the block 112p of reusable infill material 112 can be customized according to the shape and / or size of the multiple openings 104, which can help the reusable infill material 112 seal the openings 104 to prevent coating from entering the openings 104.

[0052] In other embodiments, blocks 112p of the reusable filler material 112 can be 3D printed to have a specific shape that does not necessarily conform to the shape of a single opening 104. For example, one or more blocks 112p of the reusable filler material 112 can be 3D printed to have an inner portion extending into the opening 104 and an outer portion covering the opening 104 at the outer body surface 106 of the component 100. In at least some embodiments, the outer portion of such a block 112p of the reusable filler material 112 can be wider or have a larger diameter than the inner portion of such a block 112p.

[0053] In some embodiments, the anchoring source 114 may be applied before the reusable filler material 112 is introduced to block the plurality of openings 104. More specifically, in method 200, the frame (206) for applying the anchoring source and the frame (204) for blocking the plurality of openings may be reversed. As an example, the anchoring source 114 is an adhesive material (such as moldable polymer clay), and the reusable filler material 112 is a plurality of spherical polymer beads. Before dispersing the reusable filler material 112, the adhesive material is applied to the component 100 such that, upon dispersion, the spherical polymer beads (the spherical polymer beads are blocks 112p of the reusable filler material 112) are embedded in the adhesive material at the plurality of openings 104; the adhesive material acts as an anchor to hold the spherical polymer beads in place within the openings 104. In other embodiments, the reusable filler material 112 may be dispersed or placed in the anchoring source 114, for example, as Figure 4E As shown, individual blocks 112p of reusable filler material 112 can be embedded in individual blocks of adhesive anchoring source 114, and then the blocks of anchoring source 114 in which reusable filler material 112 is embedded can be applied to part 100 such that reusable filler material 112 blocks multiple openings 104. It will be understood that the materials of adhesive anchoring source 114 and reusable filler material 112 (i.e., moldable polymeric clay and spherical polymeric beads, respectively, in this example) are merely examples, and other suitable materials and / or shapes of reusable filler material 112 may also be used.

[0054] Furthermore, the anchoring source 114 can be a combination of two or more anchoring sources as described herein. As an example, the anchoring source 114 may include a magnet and a vacuum suction device applied together to anchor the reusable filler material 112 in the plurality of openings 104. Furthermore, the shapes of the applied anchoring source 114 and the block 112p of the reusable filler material 112 can simultaneously hold the reusable filler material 112 in proper position within the plurality of openings 104. For example, as described above, the block 112p of the reusable filler material 112 can be shaped as an elongated filament with a spherical head and can be formed of a magnetic material such that when the magnetic anchoring source 114 is applied, both the magnetic anchoring source 114 and the spherical head of the block 112p contribute to anchoring the reusable filler material 112 in the plurality of openings 104. For example… Figure 4B and Figure 4C As shown, the magnetic anchoring source 114 can be applied from a certain direction (e.g., from opposite surfaces of the component) to attract the magnetic portion of the reusable filler material 112 (such as ferromagnetic filaments or pins) into the opening 104. The spherical head attached to the filament or pin can have a suitable diameter to prevent the reusable filler material 112 from entering the opening 104 too far, thereby effectively blocking the opening 104 and preventing the coating material from entering. Furthermore, as described above, the head of the filament block 112p of the reusable filler material 112 can also have other shapes, such as a conical shape, a teardrop shape, etc.

[0055] Back Figure 2 Method 200 includes applying a coating to the surface of a component at a frame (208). In some embodiments, the coating is applied at room temperature, but in other embodiments, applying the coating to the surface of the component includes subjecting the component and reusable filler material to elevated temperatures, such as at least about 50°C, at least about 100°C, at least about 300°C, at least about 350°C, at least about 500°C, at least about 750°C, at least about 1000°C, or higher. In some embodiments, the coating may be a thermal barrier coating (TBC) or an environmental barrier coating (EBC) for a turbine engine component. In some embodiments, such as Figure 2As shown, applying the coating includes a box (210) for performing the coating process at a first temperature, and optionally a box (212) for performing a heat treatment process at a second temperature. As described above, the coating process can be a line-of-sight deposition process (such as a thermal spraying process, a physical vapor deposition (PVD) process, or a sputtering technique) or another suitable process (such as a slurry-based process or a chemical vapor deposition (CVD) process). In at least some embodiments, the second temperature is greater than the first temperature. For example, the second temperature is at least about 300°C, such that the first temperature is below about 300°C. In various embodiments, the second temperature or heat treatment temperature can be at least about 300°C, at least about 500°C, at least about 750°C, at least about 1000°C, at least about 1200°C, at least about 1500°C, at least about 1800°C, at least about 2000°C, or higher. However, as mentioned above, the frame (212) is optional, and in some embodiments, method 200 includes a frame (210) for performing the coating process without performing the heat treatment process, i.e., the frame (212) is omitted in these embodiments.

[0056] Figure 6 and Figure 7 The coating and heat treatment processes described herein are illustrated schematically. Figure 6 The diagram shows a component 100 coated with a coating 116, while a reusable filler material 112 is anchored in a plurality of openings 104 by an anchoring source 114, thereby preventing the coating 116 from entering the plurality of openings 104. Figure 7 The image shows a heat treatment process performed on a component 100 to which coating 116 has been applied. For example... Figure 6 and Figure 7 As shown, the coating process and the heat treatment process can be carried out in chamber 118, etc., for example, to control the environment, such as temperature, pressure, atmosphere, etc. It will be understood that the coating process and the heat treatment process can be carried out in the same chamber 118 or in different chambers. Furthermore, as described in more detail below, in some embodiments, the reusable filler material 112 can be removed prior to the heat treatment process.

[0057] Return to reference Figure 2Method 200 may optionally include removing the anchoring source at block (214). For example, in embodiments where no anchoring source is applied, removal of the anchoring source is not required; therefore, block (214) of method 200 is optional. However, in embodiments utilizing an anchoring source, removal of the anchoring source may be necessary to enable removal of the reusable filler material from multiple openings. For example, in the case where anchoring source 114 is a magnet, the magnet or magnetic force is removed so that the reusable filler material 112 is no longer held in place by magnetic force within opening 104. In embodiments where anchoring source 114 is an adhesive material, the adhesive material may be physically removed (e.g., the reusable filler material 112 is adhered to or retained therein, such that the reusable filler material 112 is removed along with the adhesive material), or it may be chemically or thermally removed. For example, a chemical reaction or a temperature above a threshold temperature (e.g., in air or a specific atmosphere) may cause the adhesive material to decompose or degrade, thereby removing anchoring source 114. The threshold temperature can be higher than the initial temperature at which the coating process is carried out, for example, to ensure that the reusable filler material 112 remains in place during the coating process.

[0058] like Figure 2 As shown in boxes (216) and (218) in the figure, method 200 includes removing reusable filler material from multiple openings and collecting the reusable filler material. More specifically, removing the reusable filler material from multiple openings allows the component with the new coating applied to be passed to the next stage, for example, for further repair or assembly within a structure such as a gas turbine engine. Figure 8 The removal and collection of reusable filler material 112 from component 100 are illustrated. The reusable filler material 112 can be removed from the plurality of openings 104 in any suitable manner, for example, by blowing air from the internal cavity 108 through the openings 104 to remove the reusable filler material 112 therefrom, by agitating component 100 to remove the reusable filler material 112 from the openings 104, by physically removing the reusable filler material 112 from the openings 104, etc. It will be understood that, in order to remove the reusable filler material 112 from the openings 104, component 100 can be agitated in the same mode or direction and / or at the same frequency as agitating component 100 as described above to self-assemble the reusable filler material 112 into the plurality of openings 104, or at least one of the agitation mode, direction, or frequency can be different from agitating component 100 to self-assemble the reusable filler material 112 into the plurality of openings 104.

[0059] In some embodiments, the reusable filler material 112 is removed from the plurality of openings 104 after the coating process and before the heat treatment process, rather than after coating and heat treatment. That is, the block (216) for removing the reusable filler material is performed after the block (210) for the coating process and before the block (212) for the heat treatment process. Thus, the heat treatment process can be performed after the removal of the reusable filler material 112. It will be understood that in such embodiments, if the reusable filler material 112 is held in place by the anchoring source 114, the method also includes removing the anchoring source as shown at (214) after the block (210) for the coating process and before the block (216) for removing the reusable filler material, which is also performed before the block (212) for the heat treatment process.

[0060] It is worth noting that, in Figure 9 In the depicted embodiments, the reusable filler material 112 is recovered after coating 116 is applied to component 100. In at least some embodiments, the reusable filler material is collected such that it can be reused in another coating process. For example, the reusable filler material 112 is collected such that it can be used to plug openings in a second component, allowing the second component to have the coating applied thereto. That is, the reusable filler material 112 is formed of a material capable of withstanding the coating process and, optionally, the heat treatment process (if a heat treatment process is performed before removing the reusable filler material 112), such that it can be reused in another coating process to plug openings. As a non-exhaustive list of examples, the reusable filler material 112 can be formed of glass, glass ceramics, metals (such as iron materials or superalloys), ceramics (such as sintered ceramics or unsintered or green ceramics (including materials such as alumina, zirconium oxide, silicon nitride, silicon carbide, or porcelain)), or polymers. The reusable filler material 112 may be formed of a material capable of withstanding temperatures of at least about 100°C (such as about 200°C, about 350°C, about 500°C, about 650°C, about 750°C, about 1000°C, about 1500°C, about 1750°C or higher).

[0061] like Figure 2As shown, method 200 may optionally include cleaning the frame (220) of the reusable filler material. For example, after collecting the reusable filler material 112, it may be cleaned using a suitable cleaning agent and / or cleaning process to remove any debris or other foreign matter from the reusable filler material 112 that may, for example, hinder the effectiveness of the reusable filler material 112 in reuse. Furthermore, method 200 may be repeated after collecting the reusable filler material at frame (218) and optionally cleaning it at frame (220). For example, if the coating 116 applied to component 100 is damaged, method 200 may be repeated on component 100 to remove the coating 116, plug the multiple openings 104 with the reusable filler material 112, apply a new coating, and then remove and collect the reusable filler material 112. Reference Figure 9 In another embodiment, the reusable filler material 112 can be used for a separate second component 100-2 to apply a coating to the second component 100-2. For example, component 100 can be a first rotor blade of a first turbine stage of a gas turbine engine, and the second component 100-2 can be a second rotor blade of the first turbine stage of a gas turbine engine, such that component 100 and the second component 100-2 are identical or substantially identical. However, in other embodiments, component 100 and the second component 100-2 do not need to be substantially identical, but may only have similar openings defined therein, such that the reusable filler material 112 can be used for each of component 100 and the second component 100-2.

[0062] like Figure 9 As shown, the second component 100-2 has a plurality of openings 104-2, which may be the same as or similar to the plurality of openings 104 of component 100. That is, the reusable filler material 112 may have a suitable size and / or shape to adequately seal the openings 104-2 of the second component 100-2 when a coating is applied to the second component 100-2. The reusable filler material 112 can be removed and collected from the second component, for example, for reuse in a third, fourth, fifth, sixth, or more components to seal a third plurality of openings, a fourth plurality of openings, and so on.

[0063] It will be understood that while this document describes reusable filler materials, the shape, raw materials, placement techniques, etc., of materials used to block multiple openings in a component (such as cooling holes in a gas turbine engine) can also be applied to non-reusable filler materials. That is, filler materials constructed as described herein can be single-use filler materials. For example, filler materials can be pastes or other types of materials that are burned off, dissolved, or removed in a manner unsuitable for reuse. As another example, relatively inexpensive filler materials can be chosen that are shaped or formed as described herein and / or placed in openings in a component, discarded after removal from the openings following the coating process without reuse.

[0064] Therefore, as described herein, this subject matter provides a method for plugging openings in a component with a reusable filler material for a coating process, and then removing the reusable filler material for use in another component. For example, the method described herein describes a reusable filler material that plugs openings defined in the surface of a component such that the openings are substantially unobstructed after a coating is applied to the surface, and that the reusable filler material can be collected and reused after the coating is applied to the component. Reusable filler materials allow for time and cost savings, for example, by avoiding labor-intensive tasks such as re-drilling numerous cooling holes in gas turbine engine components, and by reducing the amount of filler material required for multiple coating processes or multiple components (because the reusable filler material can be used for more than one coating process). Other advantages of the subject matter described herein can also be realized by those skilled in the art.

[0065] Further aspects of this disclosure are provided by the subject matter of the following clauses:

[0066] A method of coating a gas turbine engine component includes: plugging a plurality of openings defined in a surface of the gas turbine engine component with a reusable filler material; applying a coating to the surface of the gas turbine engine component; removing the reusable filler material from the plurality of openings; and collecting the reusable filler material.

[0067] A method of coating a gas turbine engine component includes: plugging a plurality of openings defined in a surface of the gas turbine engine component with a reusable filler material; applying an anchoring source to the reusable filler material to retain the reusable filler material in the plurality of openings; applying a coating to the surface of the gas turbine engine component; removing the reusable filler material from the plurality of openings; and collecting the reusable filler material.

[0068] According to any of the foregoing provisions, applying the coating to the surface of the gas turbine engine component includes performing a coating process, which is a line-of-sight deposition process.

[0069] According to any of the foregoing provisions, applying the coating to the surface of the gas turbine engine component includes: performing a coating process at a first temperature; and performing a heat treatment process at a second temperature, wherein the second temperature is greater than the first temperature.

[0070] According to any of the foregoing clauses, the second temperature is at least about 300°C.

[0071] The method according to any of the foregoing clauses, wherein the anchoring source is a magnet and the reusable filler material is a magnetic material.

[0072] According to any of the foregoing provisions, the anchoring source is a vacuum suction device.

[0073] The method according to any of the foregoing clauses, wherein the anchoring source is an adhesive material.

[0074] The method according to any of the foregoing clauses, wherein the anchoring source is two or more of a magnet, a vacuum suction device, or an adhesive material.

[0075] According to any of the foregoing clauses of the method, the reusable filler material comprises a plurality of blocks, and at least one of the plurality of blocks of the reusable filler material has an elongated filament shape with a shaped head.

[0076] According to any of the foregoing clauses, blocking the plurality of openings with the reusable filler material includes agitating at least one of the gas turbine engine components or the reusable filler material to self-assemble the reusable filler material into the plurality of openings.

[0077] According to any of the foregoing clauses of the method, the reusable filler material comprises a plurality of blocks, wherein at least one of the plurality of blocks of the reusable filler material has a shape complementary to the shape of at least one of the plurality of openings.

[0078] According to any of the foregoing clauses of the method, the reusable filler material comprises a plurality of blocks, and at least one of the plurality of blocks of the reusable filler material has a spherical shape, a conical shape, or an elongated filament shape.

[0079] According to any of the foregoing clauses of the method, wherein the gas turbine engine component is an airfoil and the plurality of openings are a plurality of cooling holes defined in the airfoil.

[0080] The method according to any of the foregoing clauses further includes, after collecting the reusable filler material: plugging a second plurality of openings defined in the surface of the second gas turbine engine component with the reusable filler material; applying a coating to the surface of the second gas turbine engine component; removing the reusable filler material from the second plurality of openings; and collecting the reusable filler material.

[0081] A method of coating a gas turbine engine component includes: plugging a plurality of openings defined in a surface of the gas turbine engine component with a reusable filler material, wherein an anchoring source holds the reusable filler material in the plurality of openings; performing a coating process to apply a coating to the surface of the gas turbine engine component, the coating process including a line-of-sight deposition process; removing the anchoring source; removing the reusable filler material from the plurality of openings; and collecting the reusable filler material.

[0082] According to any of the foregoing provisions, the anchoring source is at least one of a magnet, a vacuum suction device, or an adhesive material.

[0083] According to any of the foregoing clauses, the reusable filler material comprises a plurality of blocks, and blocking the plurality of openings comprises: placing the plurality of blocks together with the gas turbine engine component; and agitating at least one of the plurality of blocks or the gas turbine engine component such that the plurality of blocks self-assemble in the plurality of openings to block the plurality of openings with the reusable filler material.

[0084] According to any of the foregoing clauses of the method, the reusable filler material extends beyond the plurality of openings and the surface of the gas turbine engine component, such that the coating is discontinuous at the plurality of openings.

[0085] The method according to any of the foregoing clauses further includes cleaning the reusable filler material after collecting it.

[0086] According to any of the foregoing clauses, the gas turbine engine component is a ceramic matrix composite (CMC) component, and the coating is an environmental barrier coating (EBC).

[0087] This written description uses examples to disclose embodiments of this disclosure, including best practices, and also enables any person skilled in the art to practice this disclosure, including making and using any apparatus or system and performing any combined methods. The patentable scope of this disclosure is defined by the claims and may include other examples that would occur to a person skilled in the art. Such other examples are intended to fall within the scope of the claims if they include structural elements that are not indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A method for coating gas turbine engine components, characterized in that, include: Seal the multiple openings defined in the surface of the gas turbine engine component with reusable filler material; An anchoring source is applied to the reusable filler material to retain the reusable filler material in the plurality of openings; The coating is applied to the surface of the gas turbine engine component; Remove the reusable filler material from the plurality of openings; as well as Collect the reusable filler material.

2. The method according to claim 1, characterized in that, in, Applying the coating to the surface of the gas turbine engine component includes performing a coating process, which is a line-of-sight deposition process.

3. The method according to claim 1, characterized in that, in, Applying the coating to the surface of the gas turbine engine component includes: The coating process is carried out at a first temperature; and The heat treatment process is carried out at a second temperature. The second temperature is greater than the first temperature.

4. The method according to claim 3, characterized in that, in, The second temperature is at least about 300°C.

5. The method according to claim 1, characterized in that, in, The anchoring source is a magnet, and the reusable filler material is a magnetic material.

6. The method according to claim 1, characterized in that, in, The anchoring source is a vacuum suction device.

7. The method according to claim 1, characterized in that, in, The anchoring source is an adhesive material.

8. The method according to claim 1, characterized in that, in, The anchoring source is two or more of a magnet, a vacuum suction device, or an adhesive material.

9. The method according to claim 1, characterized in that, in, The reusable filler material comprises a plurality of blocks, and at least one of the plurality of blocks of the reusable filler material has an elongated filament shape with a shaped head.

10. The method according to claim 1, characterized in that, in, Blocking the plurality of openings with the reusable filler material includes agitating at least one of the gas turbine engine components or the reusable filler material to self-assemble the reusable filler material into the plurality of openings.

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