Method for coating a substrate with hole(s)

Abstract

To provide a coating method for maintaining an original shape and dimension of apertures or cooling holes in coated components.SOLUTION: A coating method includes: providing a component having at least one aperture formed in a surface thereof; additively manufacturing a hollow member on a portion of the surface to define a space above each aperture, the portion of the surface being adjacent to the aperture, the hollow member having an inner peripheral geometry complementary to a peripheral geometry of at least one of the apertures; applying at least one coating onto the surface of the component and around the hollow member to form an applied coating having an applied coating thickness; and removing at least a portion of the hollow member to make a top portion of the hollow member coplanar with the applied coating to expose the space through the applied coating.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates generally to methods for coating substrates. In particular, the present disclosure relates to a coating method for selectively coating a substrate having pores, and to a coated substrate having pores formed by the coating method. [Background technology]

[0002] When turbines are used in aircraft or power generation, they are typically operated at as high a temperature as possible to increase operational efficiency. Because high temperatures can damage the alloys used in the components, various techniques have been used to increase the operating temperatures of metal components. One technique calls for incorporating internal cooling channels into the component through which cool air is forced during engine operation. Holes or cooling holes can be formed in the substrate by techniques such as waterjet machining and / or electrical discharge machining (EDM). Cooling air (usually provided by the engine's compressor) is delivered through the holes from the cooler side of the component wall to the hot side. As long as the holes are open, the rushing air helps prevent a drop in temperature at the hot metal surface and prevents the component from melting or otherwise deteriorating.

[0003] Another technique for protecting metal components and effectively increasing their actual operating temperatures involves the use of coatings such as bond coats, thermal barrier coatings (TBCs), or environmental barrier coatings (EBCs). TBCs are typically ceramic-based. Coating systems often also include a bond coat disposed between the ceramic coating and the substrate to improve adhesion. The use of TBCs with cooling holes is often an effective means of protecting engine components. However, incorporating both coating systems is extremely difficult. For example, cooling holes often cannot be formed in engine components after the TBC is applied. This is because lasers typically cannot effectively penetrate both the ceramic material and the metal to form the hole pattern and may potentially crack the TBC. If the cooling holes are formed before the coating system is applied, they may be covered or at least partially blocked when the coating is applied. Summary of the Invention

[0004] A first aspect of the present disclosure provides a coating method for a component with at least one hole, the coating method including the steps of: providing a component having at least one hole formed in a surface thereof; additively manufacturing a hollow member on a portion of the surface to define a space above each hole, the portion of the surface adjacent to the hole, the hollow member having an inner circumferential geometric shape complementary to the periphery geometric shape of at least one of the holes; applying at least one coating on the surface of the component and around the hollow member to form an applied coating having an applied coating thickness; and removing at least a portion of the hollow member to make an upper portion of the hollow member flush with the applied coating and expose the space through the applied coating, leaving a lower portion of the hollow member defining the space through the applied coating.

[0005] A second aspect of the present disclosure provides a coated component, the component comprising: a surface; at least one hole formed on the surface; a coating layer on the surface, the coating layer including at least one additively manufactured hollow member extending from the surface to a top surface, each hollow member defining a space above a respective one of the at least one hole, the periphery of the hollow member being co-located with each of the at least one hole and having an inner periphery geometric shape complementary to the periphery geometric shape of a respective one of the at least one hole; and a coating material sprayed onto and around the surface of the hollow member, the coating material having an upper surface that is co-planar with the portion of the hollow member after at least one portion of the hollow member is removed.

[0006] The exemplary aspects of the present disclosure are designed to solve the problems described herein and / or other problems not discussed.

[0007] These and other features of the present disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure, taken in conjunction with the accompanying drawings, which illustrate various embodiments of the disclosure. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a component of the present disclosure. [Figure 2] 1 is a flowchart of a process according to the present disclosure. [Figure 3] 2 is a cross-sectional view of the component of FIG. 1 having a hollow member formed thereon with a plurality of holes in accordance with the present disclosure. [Figure 4] 2 is a cross-sectional view of the component of FIG. 1 with a hollow member and a coating formed thereon, the hollow member including a plurality of holes, in accordance with the present disclosure. [Figure 5] 2 is a cross-sectional view of the component of FIG. 1 with a hollow member and a coating formed thereon, the hollow member being provided with a plurality of holes, and with a portion of the hollow member removed, in accordance with the present disclosure. [Figure 6] 10 is a cross-sectional view of a component according to another aspect of the present disclosure having a hollow member formed thereon with a plurality of holes according to the present disclosure. [Figure 7] 1 is a cross-sectional view of a component according to another aspect of the present disclosure, including a plurality of holes, a hollow member, and a coating formed thereon, according to the present disclosure; [Figure 8] 1 is a cross-sectional view of a component according to another aspect of the present disclosure, comprising a plurality of holes, a hollow member and a coating formed thereon, and a portion of the hollow member removed, according to the present disclosure; [Figure 9] 1 is a diagram of a spray device having components according to the present disclosure.

[0009] It should be noted that the drawings of the present disclosure are not to scale. The drawings are intended to depict only typical aspects of the present disclosure and therefore should not be considered limiting of the scope of the present disclosure. In the drawings, like numbers represent like elements between the drawings. DETAILED DESCRIPTION OF THE INVENTION

[0010] At the outset, in order to clearly explain the present technology, it is necessary to select certain terminology when referring to and describing relevant components within a turbine. Wherever possible, common industry terminology is used and utilized consistent with its accepted meaning. Unless otherwise noted, such terminology should be given a broad interpretation consistent with the context of this application and the scope of the appended claims. Those skilled in the art will recognize that in many cases, a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single component may include multiple components and may be referred to in other contexts as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single component.

[0011] Additionally, several descriptive terms may be used regularly herein, and it will prove useful to define these terms at the beginning of this section. These terms and their definitions are as follows, unless otherwise specified: As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a working fluid through a turbine engine, or a fluid such as, for example, the flow of air through a combustor or a coolant through one of the turbine's component systems. The term "downstream" corresponds to the direction of fluid flow, and the term "upstream" refers to the opposite direction of flow. The terms "forward" and "aft," unless otherwise specified, refer to directions, with "forward" referring to the front end or compressor end of the engine and "aft" referring to the aft end or turbine end of the engine.

[0012] It is often desired to describe components located at different radial positions relative to the central axis. The term "radial" refers to movement or position perpendicular to the axis. For example, if a first component is located closer to the axis than a second component, the first component may be described herein as being "radially inward" or "inward" of the second component. Conversely, if a first component is located farther from the axis than the second component, the first component may be described herein as being "radially outward" or "outward" of the second component. The term "axial" refers to movement or position parallel to the axis. Finally, the term "circumferential" refers to movement or position around the axis. It will be understood that such terms may be applied relative to the central axis of the turbine.

[0013] Additionally, as noted below, certain descriptive terms may be used herein in a conventional manner: the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to denote the location or importance of the individual components.

[0014] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural unless expressly stated otherwise. It should be further understood that the terms "comprise" and / or "comprising," as used herein, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or sets thereof. "Optional" or "optionally" means that the subsequently-stated event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not occur.

[0015] When an element or layer is referred to as "on," "engaged," "connected," or "coupled" to another element or layer, it can be directly on, engaged, connected, or coupled to the other element or layer, or intervening elements or layers may be present. Conversely, when an element is referred to as "directly on," "directly engaged," "directly connected," or "directly coupled" to another element or layer, there may not be intervening elements or layers. Other terms used to describe relationships between elements should be interpreted similarly (e.g., "between" versus "directly between," "adjacent to" versus "directly adjacent to," etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0016] As noted above, the present disclosure provides methods for coating components. In particular, the present disclosure relates to coating methods for selectively coating components with pores, and coated components with pores formed by the coating methods.

[0017] 1 , in one embodiment, component 100 includes any suitable component having at least one hole 109 formed therein. In another embodiment, component 100 includes any suitable component used in applications subject to temperature changes, such as, but not limited to, power generation systems (e.g., gas turbines, jet turbines, and other turbine assemblies). Suitable example components 100 include, but are not limited to, nozzles, blades, vanes, shrouds, rotor blades, transition pieces, liners, or combinations thereof. Hole 109 includes any opening formed in exterior surface 102 of component 100, such as, but not limited to, cooling holes (e.g., trench cooling holes, diffuser-shaped cooling holes, straight cooling holes, angled cooling holes), openings for providing fuel flow, or combinations thereof, and other cooling hole configurations now known or later developed.

[0018] 1, component 100 is illustratively shown as a turbine blade having an airfoil section 103, a platform section 105, and a dovetail section 107. Airfoil section 103 has a plurality of holes 109 formed therein that function as cooling holes.

[0019] In one embodiment, component 100 is made from a high-temperature, oxidation- and corrosion-resistant alloy having high-temperature strength, such as a nickel-, cobalt-, or iron-based superalloy. In another embodiment, component 100 includes a coating 400 ( FIG. 4 ) applied to the exterior surface 102 of the component. Coating 400 may include any suitable coating that covers at least a portion of and / or provides protection (e.g., improved heat resistance, improved corrosion resistance) to exterior surface 102, such as, but not limited to, a bond coat, a thermal barrier coating (TBC), an environmental barrier coating (EBC), or a combination thereof, or other coating now known or later developed. Suitable examples of bond coats include, but are not limited to, MCrAlX coatings, where M is cobalt, nickel, iron, or a combination thereof, and X is yttrium (Y) and / or silicon (Si) and / or at least one rare earth element or reactive element, such as hafnium (Hf). Suitable examples of TBCs include, but are not limited to, ceramic coatings such as zirconium oxide (ZrO), whose crystalline structure may be partially or fully stabilized by the addition of yttrium oxide (YO), aluminum oxide, zirconium oxide, hafnium oxide, yttria-stabilized zirconium oxide, metallic materials, silicon-based materials, graphite, aluminum oxide, yttria-stabilized zirconia, and combinations thereof, or other coatings now known or hereafter developed. Generally, EBC systems include two or more layers of coating materials (e.g., bond coats and / or thermal barrier coats), often rare earth or yttrium silicate, each serving a specific purpose. Thus, this disclosure focuses on the application of layers, as an EBC may include layers (and thus, reference to layers refers to multiple layers in an EBC).

[0020] 2-5, in one embodiment, a first coating method 200 includes providing a component 100 having a hole 109 formed in its exterior surface 102 (step 201), and then additively manufacturing / printing (step 203) at least one hollow member 300 ( FIG. 3 ) over a portion of the exterior surface 102 at the hole 109 to define a space 309 ( FIG. 4 ) above the hole 109. After the hollow member 300 is printed (step 203), at least one coating is applied (step 205) onto the exterior surface 102 of the component 100 and around the hollow member 300 to form a layer of coating 400 ( FIG. 4 ) having an applied coating thickness 403 ( FIG. 4 ).

[0021] Once coating 400 is formed, a portion of hollow member 300 is removed (step 207) to expose spaces 309 through coating 400 down to holes 109. Alternatively, if desired and to reduce the overall thickness of coating 400, a portion of coating 400 can be removed (step 207) by removing a portion of hollow member 300, thereby exposing spaces 309 through coating 400 down to holes 109 with a reduced coating thickness 403.

[0022] In one embodiment, hollow member 300 comprises a geometry that is complementary to holes 109. Suitable complementary geometries for holes 109 and hollow member 300 include, but are not limited to, tubular, hemispherical, square, rectangular, cylindrical, elliptical, hourglass, chevron, any other complementary geometric shape that can extend from outer surface 102 at holes 109 (e.g., planar or non-planar), or combinations thereof. For example, in one embodiment, the geometry of hollow member 300 is complementary to a diffuser-shaped cooling hole.

[0023] The hollow member 300 is printed onto the exterior surface 102 of the component 100 at any suitable height to form a space 309 that is coextensive with the coating 400 after step 207. The walls of the space 309 are formed by the interior walls of the hollow member 300 and are substantially collinear with the walls of the hole 109.

[0024] For example, hollow member 300 may be printed onto outer surface 102 of component 100 around hole 109 (see FIG. 3 or FIG. 5) such that hollow member 300 extends away from outer surface 102 of component 100 at a height equal to or greater than the applied coating thickness 403. Suitable coating thickness 403 heights include, but are not limited to, up to about 2.5 millimeters (0.1 inches).

[0025] In another embodiment, the inner periphery 310 and geometry of hollow member 300 are aligned, equal, and complementary to the outer periphery 111 and geometry of bore 109. This configuration allows bore 109 and hollow member 300 to be coaxial with one another. This configuration also allows for a smooth, linear transition from bore 109 to hollow member 300, creating a substantially flush inner transition surface from bore 109 to hollow member 300.

[0026] The hollow member 300 is formed by any suitable 3D printing, printing, or additive manufacturing process (collectively referred to hereinafter as "additive manufacturing processes"), such as, but not limited to, a wide variety of processes that manufacture components by successively building up layers of material rather than removing material. As such, additive manufacturing can create the complex geometry of the hollow member 300 without the use of tools, molds, or fixtures of any kind and with little or no waste material. Instead of machining the hollow member 300 from a solid billet of material, much of which would be cut away and discarded, additive manufacturing uses only the material needed to print the hollow member 300.

[0027] Additive manufacturing techniques typically involve obtaining a three-dimensional computer-aided design (CAD) file of the component to be formed (here, the hollow member 300 on a build platform formed by the exterior surface 102 of the component 100), electronically slicing the component into layers, e.g., 18-102 micrometers thick, and creating a file with a two-dimensional image of each layer, including vectors, images, or coordinates. This file can then be loaded into a preparation software system that interprets the file so that the hollow member 300 can be constructed by different types of additive manufacturing systems. 3D printing, rapid prototyping (RP), and direct digital manufacturing (DDM) are additive manufacturing forms in which layers of material are selectively dispensed, sintered, shaped, deposited, etc., to form the hollow member 300.

[0028] Powder additive manufacturing techniques, such as direct metal laser melting (DMLM) (also known as selective laser melting (SLM)), involve sequentially fusing layers of powder together to form a component. More specifically, fine powder layers are uniformly distributed over a powder bed using an applicator, which then sequentially melts them. Each applicator is equipped with an applicator element—in the form of a lip, brush, blade, or roller made of metal, plastic, ceramic, carbon fiber, or rubber—that spreads the powder evenly over the build platform. The powder bed can be moved along a vertical axis. The process takes place in a processing chamber with a precisely controlled atmosphere. As each layer is formed, each two-dimensional slice of the component's geometry can be fused together by selectively melting the powder. Melting can be achieved with a high-power melting beam, such as, but not limited to, a 100-watt ytterbium laser, which completely welds (melts) the metal powder to form a solid. The melting beam is moved in the XY direction using a scanning mirror and has sufficient intensity to completely weld (melt) the powder to form a solid. For each subsequent two-dimensional layer, the powder bed can be lowered and the process repeated until the component is fully formed.

[0029] 2-5 , after printing / additive manufacturing the hollow member 300 (step 203), at least one coating 400 is applied (step 205) onto the exterior surface 102 of the component 100 by any suitable application method to form a coating 400 having an applied coating thickness 403. Suitable application methods include, but are not limited to, air plasma spraying, high velocity oxygen fuel (HVOF) spraying, or electron beam physical vapor deposition, or other application methods now known or hereafter developed. During application of the at least one coating (step 205), the orientation and geometry (described below) of the hollow member 300 relative to the coating being applied reduces or eliminates deposition of the coating 400 material in any portion of the hollow member 300, such as in the holes 109 and spaces 309 (see FIG. 4 ).

[0030] Once the coating(s) 400 are applied (step 205), the top portion 301 of the hollow member 300 may be removed (step 207). Further, as described herein, portions of the coating 400 may be removed by any suitable removal method to provide the desired coating thickness 403, possibly if the applied coating 400 (step 205) is too thick. Thus, after removal, the top surface 410 ( FIG. 5 ) of the coating 400 is flush with the remainder of the hollow member 300. Suitable removal methods include, but are not limited to, machining, sanding, grit blasting, etching, polishing, or a combination thereof. For example, in one embodiment, removing the coating includes polishing the coating 400 with a diamond pad.

[0031] In one aspect of the present disclosure, the upper portion 301 ( FIG. 4 ) of the hollow member 300 comprises an upper geometry that is different from the lower geometry of the lower portion 303. For example, and by way of example only and not intended to limit embodiments of the present disclosure in any way, hollow member 350 of FIG. 4 includes a rectangular printed upper section. This different upper geometry may be such that if hollow member 300 is open at the end away from hole 109 (see hollow member 320 of FIG. 4 having open end 321), hollow member 300 is configured to exclude coating 400 from entering hollow member 300. By printing / additively manufacturing hollow member 300, the upper portion 301 can be closed (see hollow member 330 of FIG. 4 ), particularly when coating 400 is sprayed on, or can be open enough to resist the ingress of coating 400.

[0032] Additionally, as described herein, the geometry of the lower portion 303 can match the geometry of the holes 109, and the geometry of the upper portion 301 can match the geometry of the holes 109 or comprise any other configuration or shape extending from the lower portion 303. For example, and not intended to limit the disclosure in any way, the hollow member 300 at the lower portion 303 can have a geometry that matches the circular holes 109 and transition to an oval shape at the upper portion 301 extending away from the outer surface 102.

[0033] Once the top portion 301 is removed (step 207), portions of the top and bottom portions 301, 303 remain, defining the space 309, as shown in Figure 5. In one embodiment, the geometric shape of the space 309 includes, but is not limited to, cylindrical, spherical, square, rectangular, dome-shaped, oval, trapezoidal, curved, rectilinear, twisted, irregular, any other shape that allows flow therethrough, or combinations thereof.

[0034] A further aspect of the present disclosure includes printing / additive manufacturing an angled hollow member 500 with angled holes 109 (including but not limited to those used in film-cooled turbine components), as shown in Figures 6-8. Like reference numbers are used for like elements.

[0035] 6-8 , the angled hollow member 500 is printed onto a portion of the exterior surface 102 at the angled hole 109, defining a space 509 above the angled hole 109, with the hole 109 typically being oval or elliptical in shape intersecting the surface 102. As in the above embodiment, the angled hollow member 500 comprises a complementary geometry to the hole 109. Additionally, the inner perimeter 510 and geometry of the angled hollow member 500 may be equal to and complementary to the outer perimeter 111 and geometry of the angled hole 109 at the surface 102. Thus, the angled hole 109 and the angled hollow member 500 substantially form a coplanar transition surface from the angled hole 109 to the hollow member 500, and the hollow member 500 is substantially collinear with the wall of the angled hole 109.

[0036] The hollow member 500 is printed onto the exterior surface 102 of the component 100 at any suitable height to form a space 509 with the applied coating 400. The walls of the space 509 are formed by the interior walls of the hollow member 500, and the walls of the space 509 are substantially collinear with the walls of the hole 109.

[0037] The hollow member 500 is printed (using any suitable printing or additive manufacturing process described above) onto the exterior surface 102 of the component 100 around the angled hole 109 such that the hollow member 500 extends away from the exterior surface 102 of the component 100 at an angle that matches the angle of the hole 109. This configuration allows the hole 109 and hollow member 500 to be coaxial with one another. As described above, the hollow member 500 has a height that is equal to or greater than the thickness 403 of the applied coating.

[0038] After printing / additively manufacturing the hollow member 500, at least one coating 400 is applied onto the exterior surface 102 of the component 100 by any suitable application method to form a coating 400 having an applied coating thickness 403. During application of the coating(s) 400, the orientation and geometry of the hollow member 500, which is angled relative to the coating material applicator / sprayer, reduces or eliminates coating material on or within the holes 109 and spaces 509. When the top portion 501 is removed, as in FIG. 8 , portions of the top and bottom portions 501, 503 remain, defining the spaces 509. Thus, after removal, the top surface 410 of the coating is flush with the remainder of the hollow member 500. Furthermore, removal of any portions of the coating(s) 400 can be performed in conjunction with removal of the hollow member 500, if necessary to achieve the desired coating thickness 403.

[0039] With respect to the process for applying coating 400, as described above, coating(s) 400 are applied onto exterior surface 102 of component 100 by any suitable applicator / sprayer and application method to form coating 400 having applied coating thickness 403. As described above, one suitable application method is by spraying coating(s) 400.

[0040] In any of the embodiments herein, the spray coating applicator / sprayer can include a spray gun with a spray head that can be positioned at an angle relative to the hole 109 of the component 100. The angled spray head is effective in reducing spray from entering the hole 109 because the angles of the hole 109 (including those substantially perpendicular to the surface 102) and the hollow member 300, 500 will not align with the spray, and therefore the spray will not enter the hole 109 directly. Furthermore, when a printed hollow member 300, 500 is provided in the hole 109, the angled spray head can improve coverage between the hole 109 and the hollow member 300, 500. The hollow member 300, 500 should prevent any spray and coating(s) 400 from entering the hole 109, which allows for more efficient and effective consumption of the coating without wasted spray in the hole 109 that must be removed and discarded.

[0041] FIG. 9 illustrates this aspect of the embodiment having a spray gun 550 with an angled spray head 555. Additionally, the angled spray head 555 can be adjustable to move its orientation relative to the surface 102 from 0 degrees (perpendicular to the surface 102) to approximately 90 degrees, i.e., nearly parallel to the surface 102. As shown, the angled spray head 555 can direct the spray directly between the printed hollow members, as shown for set 500A, or can direct the spray offset between the printed hollow members, as shown for set 500B. One desirable angle is approximately 20 degrees from perpendicular, although this angle is not intended to limit the embodiment in any way. The hollow members 300, 500 prevent the spray and coating from entering the holes 109, thereby allowing for more efficient and effective consumption of the coating without wasted spray in the holes 109 that must be removed and discarded.

[0042] One advantage of an embodiment of the present disclosure includes maintaining the original shape and dimensions of the holes or cooling holes in the coated component. Another advantage of an embodiment is better control of airflow through the coated component. Yet another advantage is faster processing of the coated component. Another advantage of an embodiment is reduced cleaning time for the cooling holes after the component is coated or recoated. Yet another advantage includes significant labor savings, since drilling is not required to open the cooling holes after coating.

[0043] Components of the present disclosure may be used in any application that experiences temperature changes, such as power generation systems, including, but not limited to, gas turbines, steam turbines, jet turbines, and other turbine assemblies. Additionally, embodiments of the present disclosure may provide increased coating efficiency, provide holes through the coating without post-coating clearing, increased control of airflow in the coated component, reduced coating costs, reduced coating time, reduced time to clean holes after coating the component, or combinations thereof, compared to coating methods that do not use one or more of the features disclosed herein.

[0044] The above figures illustrate some of the processes involved in some embodiments of the present disclosure. In this regard, each figure or block within the flow diagrams of the figures represents a process associated with the described method embodiment. It should also be noted that in some alternative implementations, the operations described in the figures or blocks may occur out of the order shown in the figures, or may actually be performed substantially simultaneously or in reverse order, depending on the operations involved, for example. Those skilled in the art will also recognize that additional blocks describing the processes may be added.

[0045] As used herein throughout this specification and claims, approximation language can be applied to modify any quantitative expression that can reasonably vary without resulting in a change in the basic function involved. Thus, values ​​modified by terms such as "approximately," "about," and "substantially" are not limited to the exact value specified. In at least some instances, approximation language can correspond to the precision of the instrument used to measure the value. Here, and throughout this specification and claims, range limitations are combinable and / or interchangeable, and unless the context and language dictate otherwise, such ranges are identified and include all subranges encompassed therein. "About," as applied to a particular value in a range, applies to both endpoints and can indicate + / - 10% of the stated value, unless specifically dependent on the precision of the instrument used to measure the value.

[0046] The corresponding structure, material, acts, and equivalents of all means-plus-function or step-plus-function elements in the following claims are intended to encompass any structure, material, or acts for performing that function in combination with other specifically claimed claim elements. The description of the present disclosure has been presented for purposes of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the disclosure. The present embodiments were chosen and described in order to best explain the principles and practical application of the disclosure and to enable others skilled in the art to understand the disclosure in its various embodiments with various modifications as suited to the particular uses envisioned. [Explanation of symbols]

[0047] 100 components 102 Exterior / Surface 103 Airfoil Section 105 Platform Section 107 Dovetail Section 109 Angled Hole 111 Hole circumference 200 First Coating Method 201 steps 203 steps 205 steps 207 steps 300 Hollow member 301 Upper part of hollow member 303 Lower part of hollow member 309 Space 310 Inner circumference of hollow member 320 Hollow Members 321 Open end of hollow member 330 Hollow members 350 Hollow Members 400 coating 403 Coating Thickness 410 Coating Top 500 Angled Hollow Member 500A 1 set of hollow members 500B 1 set of hollow members 501 Upper part of hollow member 503 Lower part of hollow member 509 Space 510 Inner circumference of hollow member 550 spray gun 555 Angled Spray Head

Claims

1. additively manufacturing a hollow member (300, 320, 330, 350, 500) on a portion of a surface (102) of a component (100) having at least one hole (109) formed in the surface (102), wherein the hollow member (300, 320, 330, 350, 500) defines a space (309, 509) above the at least one hole (109), the portion of the surface (102) is adjacent to the at least one hole (109), and the hollow member (300, 320, 330, 350, 500) has an inner peripheral geometric shape complementary to a peripheral geometric shape of the at least one hole (109); applying at least one coating (400) onto the surface (102) of the component (100) and around the hollow member (300, 320, 330, 350, 500) to form an applied coating (400) having an applied coating thickness (403); removing at least a portion of the hollow member (300, 320, 330, 350, 500) so that an upper portion of the hollow member (300, 320, 330, 350, 500) is flush with the applied coating (400) and the space (309, 509) is exposed through the applied coating (400); A coating (400) method comprising: a lower portion of said hollow member (300, 320, 330, 350, 500) remains through said applied coating (400) to define said space (309, 509); The additive manufacturing step includes additively manufacturing the hollow member (300, 320, 330, 350, 500) extending away from the surface (102) and having a height equal to or greater than the thickness of the applied coating.

2. 10. The coating method of claim 1, wherein the coating and the hollow member comprise at least one of a thermal barrier coating composition, an environmental barrier coating composition, and a bond coat composition.

3. 2. The coating method of claim 1, wherein additively manufacturing the hollow member comprises additively manufacturing the hollow member in the same location as the at least one hole.

4. 4. The coating method of claim 3, wherein additively manufacturing the hollow member co-located with the at least one hole comprises aligning an inner periphery of the hollow member with an outer periphery of the at least one hole to define a flush transition surface therebetween.

5. 4. The coating method of claim 3, wherein the at least one hole defines an axis disposed at a non-perpendicular angle relative to the surface, and additively manufacturing the hollow member comprises additively manufacturing the hollow member in the same position as the at least one hole and coaxial with the axis of the at least one hole.

6. 10. The coating (400) method of claim 1, further comprising: the hollow member (300, 320, 330, 350, 500) and the coating (400) being selected from ceramic materials, aluminum oxide, zirconium oxide, hafnium oxide, yttria-stabilized zirconium oxide, metallic materials, silicon-based materials, graphite, aluminum oxide, yttria-stabilized zirconia, and combinations thereof.

7. The coating (400) method of claim 1, wherein the component (100) is selected from the group comprising a nozzle, a blade, a vane, a shroud, a rotor blade, a transition piece, a liner, and combinations thereof.

8. The coating (400) method of claim 1, wherein the removing step comprises machining, grit blasting, sanding, etching, polishing, or a combination thereof.

9. The coating method of claim 1, wherein applying at least one coating comprises performing air plasma spraying, high velocity oxygen fuel (HVOF) spraying, or electron beam physical vapor deposition.

10. 2. The coating method of claim 1, wherein applying at least one coating comprises spraying the coating with a spray gun, the spray gun having a spray head positioned at an angle relative to the at least one hole.

11. The coating (400) method of claim 1, further comprising removing a portion of the applied coating (400) to reduce a coating thickness (403).

12. 12. The coating (400) method of claim 11, wherein applying at least one coating (400) comprises applying the coating (400) to a thickness of up to about 2.5 millimeters (0.1 inches).

13. 12. The coating (400) method of claim 11, wherein removing the portion of the applied coating (400) further comprises removing the portion of the hollow member (300, 320, 330, 350, 500).

14. The coating (400) method of claim 1, wherein the additive manufacturing step comprises additively manufacturing the hollow member (300) having an open end.

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