Improved turbine nozzle and method of manufacturing the same

Abstract

The present invention provides a method for manufacturing a turbine (10) component and a turbine (10) component. The method includes irradiating a powder layer in a powder bed (1120) to form a fusion region. The powder bed is disposed on a build plate (1002). The method also includes the step of providing a subsequent powder layer on the powder bed (1120) by passing a recoater arm (1160) through the powder bed (1120) from a first side of the powder bed (1120). The method also includes repeating the irradiating and providing steps until a turbine nozzle assembly (201) is formed on the build plate (1002). The turbine nozzle assembly (201) includes a turbine nozzle (200) and a plurality of heat sinks (232) disposed within the turbine nozzle (200). The plurality of heat sinks (232) transfer heat away from a heat-sensitive portion of the turbine nozzle (200).

Description

Technical Field

[0001] The present disclosure generally relates to turbine nozzles. In particular, the present disclosure relates to improved structures and methods for manufacturing turbine nozzles. Background Art

[0002] Turbines are widely used in fields such as power generation. For example, a conventional gas turbine system includes a compressor section, a combustor section, and at least one turbine section. The compressor section is configured to compress air as it flows through the compressor section. The air is then directed from the compressor section to the combustor section, where it is mixed with fuel and combusted, thereby generating a hot gas stream. The hot gas stream is provided to the turbine section, which extracts energy from the hot gas stream to power the compressor, generator, and / or various other loads. Due to the complex shapes and internal geometries of many turbine components, additive manufacturing processes can be utilized to properly manufacture the components within tight design tolerances. For example, in a typical turbine, additive manufacturing processes can be used to manufacture one or more rotor blades, shrouds, airfoils, fuel nozzles, and / or combustion components or subcomponents.

[0003] In contrast to subtractive manufacturing methods, additive manufacturing processes typically involve the accumulation of one or more materials to create a net-shape or near-net-shape (NNS) object. While "additive manufacturing" is an industry-standard term, it encompasses a variety of manufacturing and prototyping techniques known by various names, including freeform fabrication, 3D printing, and rapid prototyping / machining. Additive manufacturing techniques enable the creation of complex parts from a variety of materials. Generally, free-standing objects can be made from computer-aided design (CAD) models. Specific types of additive manufacturing processes use an energy beam (e.g., an electron beam or electromagnetic radiation (such as a laser beam)) to sinter or fuse powdered material, forming a solid three-dimensional object in which the particles of the powdered material are bonded together. Various material systems are used, such as engineering plastics, thermoplastic elastomers, metals, and ceramics. Laser sintering or melting is a notable additive manufacturing process for the rapid production of functional prototypes and tools. Applications include the direct creation of complex workpieces, patterns for precision casting, metal molds for injection molding and die casting, and molds and cores for sand casting. Prototyping objects to enhance communication and testing of concepts during the design cycle are other common uses of additive manufacturing processes.

[0004] Selective laser sintering, direct laser sintering, selective laser melting, and direct laser melting are commonly used industry terms to refer to the creation of three-dimensional (3D) objects by sintering or melting fine powders using a laser beam. More precisely, sintering involves fusing (agglomerating) powder particles at a temperature below the melting point of the powder material, while melting involves completely melting the powder particles to form a solid homogeneous body. The physical process associated with laser sintering or laser melting involves the transfer of heat to the powder material, which then sinters or melts the powder material.

[0005] However, during the laser sintering / melting process, a three-dimensional object (such as one or more of the turbine components described above) experiences numerous thermal stresses due to the heat experienced by the melting and / or sintering of the material. These thermal stresses have been shown to cause various deformations and / or distortions in the turbine components. Therefore, there is a need for an improved method for additively manufacturing turbine components that advantageously minimizes or completely eliminates distortions in the turbine components caused by the thermal stresses experienced during the additive manufacturing process. Summary of the Invention

[0006] Aspects and advantages of methods of manufacturing turbine components and turbine components according to the present disclosure will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the technology.

[0007] According to one embodiment, a method for manufacturing a turbine nozzle for a turbine using an additive manufacturing system is provided. The method includes irradiating a powder layer in a powder bed to form a fusion region. The powder bed is disposed on a build plate. The method also includes the step of providing a subsequent powder layer on the powder bed by passing an applicator arm over the powder bed from a first side of the powder bed. The method also includes repeating the irradiating and providing steps until a turbine nozzle assembly is formed on the build plate. The turbine nozzle assembly includes a turbine nozzle and a plurality of cooling fins disposed within the turbine nozzle. The plurality of cooling fins transfer heat away from heat-sensitive portions of the turbine nozzle.

[0008] According to another embodiment, a turbine component is provided that is produced on a build plate by an additive manufacturing process. The turbine component includes an airfoil and a plurality of cooling fins. The airfoil extends between a leading end and a trailing edge fused to the build plate. The airfoil includes an outer liner segment, an inner liner segment, a pressure sidewall, and a suction sidewall. The outer liner segment and the inner liner segment are disposed opposite each other. The suction sidewall and the pressure sidewall extend between the leading end and the trailing edge and between the outer liner segment and the inner liner segment. The plurality of cooling fins are configured to transfer heat away from heat-sensitive portions of the airfoil during the additive manufacturing process.

[0009] These and other features, aspects, and advantages of the method for manufacturing a turbine component and the turbine component of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present technology and, together with the description, serve to explain the principles of the technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] This specification sets forth a complete and enabling disclosure of the method of manufacturing a turbine component and a turbine component of the present invention, including the best mode of making and using the system and method of the present invention, as will be apparent to one of ordinary skill in the art, with reference to the accompanying drawings, in which:

[0011] Figure 1 is a schematic diagram of a turbine according to an embodiment of the present disclosure;

[0012] Figure 2 is an upstream view of an exemplary combustion section of a turbomachine according to an embodiment of the present disclosure;

[0013] Figure 3 is a perspective view of an integrated burner nozzle viewed from a first side according to an embodiment of the present disclosure;

[0014] Figure 4 is a perspective view of an integrated burner nozzle viewed from a second side according to an embodiment of the present disclosure;

[0015] Figure 5 is a schematic / block diagram of an additive manufacturing system for generating an object according to an embodiment of the present disclosure;

[0016] Figure 6 shows a perspective view of a turbine nozzle according to an embodiment of the present disclosure, isolated from other components of an integrated combustor nozzle and positioned on a build plate;

[0017] Figure 7 shows a perspective view of a turbine nozzle according to an embodiment of the present disclosure, isolated from other components of an integrated combustor nozzle and positioned on a build plate;

[0018] Figure 8 shows a cross-sectional view of a turbine nozzle according to an embodiment of the present disclosure, isolated from other components of an integrated combustor nozzle and positioned on a build plate;

[0019] Figure 9 shows a first tooth end of a heat sink according to an embodiment of the present disclosure;

[0020] Figure 10 A second tooth end of a heat sink according to an embodiment of the present disclosure is shown.

[0021] Figure 11 is a flow chart of a method for manufacturing a turbine nozzle according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0022] Reference will now be made in detail to embodiments of the present invention assembly, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the present invention's technology, rather than as a limitation of the present technology. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention's technology without departing from the scope or essence of the present invention as protected by the claims. For example, a feature shown or described as part of one embodiment can be used in another embodiment to produce yet another embodiment. Therefore, this disclosure is intended to encompass these modifications and variations that fall within the scope of the appended claims and their equivalents.

[0023] The detailed description uses numerical and letter designations to refer to features in the drawings. Similar or analogous designations in the drawings and the description have been used to refer to similar or analogous components of the present invention. As used herein, the terms "first," "second," and "third" are used interchangeably to distinguish one component from another and are not intended to indicate the position or importance of each component.

[0024] As used herein, the terms "upstream" (or "upward") and "downstream" (or "downward") refer to relative directions relative to the flow of fluid in a fluid pathway. For example, "upstream" refers to the direction from which the fluid is flowing, and "downstream" refers to the direction towards which the fluid is flowing. The term "radially" refers to a relative direction that is substantially perpendicular to the axial centerline of a particular component, the term "axially" refers to a relative direction that is substantially parallel and / or coaxially aligned with the axial centerline of a particular component, and the term "circumferentially" refers to a relative direction that extends around the axial centerline of a particular component. Approximate terms, such as "substantially," "substantially," "approximately," or "about" include values ​​that are within ten percent of the specified value. When used in the context of an angle or direction, such terms include values ​​that are within ten degrees of the specified angle or direction. For example, "substantially vertical" includes directions that are within ten degrees of vertical in any direction (e.g., clockwise or counterclockwise).

[0025] The terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when used in this specification, the terms "comprises" and / or "comprising" specify the presence of stated features, integers, steps, operations, elements, and / or parts, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, and / or groups thereof.

[0026] As described below, exemplary embodiments of the present subject matter involve the use of additive manufacturing machines or methods. As used herein, the terms "additive manufacturing" or "additive manufacturing techniques or processes" generally refer to a manufacturing process in which successive layers of material are deposited on top of one another to "build up" a three-dimensional component layer by layer. The successive layers are typically fused together to form a unitary component, which may have various integral subcomponents.

[0027] While additive manufacturing techniques are described herein as enabling the fabrication of complex objects, typically in a vertical direction, by building the object point by point, layer by layer, other fabrication methods are possible and within the scope of the present subject matter. For example, while the discussion herein discusses adding material to form successive layers, one skilled in the art will appreciate that the methods and structures disclosed herein can be practiced using any additive manufacturing technique or fabrication technology. For example, embodiments of the present invention can utilize additive layer processes, subtractive layer processes, or hybrid processes.

[0028] Suitable additive manufacturing techniques according to the present disclosure include, for example, fused deposition modeling (FDM), selective laser sintering (SLS), 3D printing (such as by inkjet and laser jet), photolithography (SLA), direct selective laser sintering (DSLS), electron beam sintering (EBS), electron beam melting (EBM), laser engineered net shape (LENS), laser net shape manufacturing (LNSM), direct metal deposition (DMD), digital light processing (DLP), direct selective laser melting (DSLM), selective laser melting (SLM), direct metal laser melting (DMLM) and other known processes.

[0029] In addition to using a direct metal laser sintering (DMLS) or direct metal laser melting (DMLM) process (in which an energy source is used to selectively sinter or melt portions of a powder layer), it will be understood that, according to an alternative embodiment, the additive manufacturing process can be a "binder jetting" process. In this regard, binder jetting involves continuously depositing layers of additive powder in a manner similar to that described above. However, binder jetting does not use an energy source to generate an energy beam to selectively melt or fuse the additive powder, but rather involves selectively depositing a liquid binder onto each powder layer. The liquid binder can be, for example, a photocurable polymer or another liquid binder. Other suitable additive manufacturing methods and variations are intended to be within the scope of the present subject matter.

[0030] Referring now to the accompanying drawings, Figure 1A schematic diagram of one embodiment of a turbine is shown, which in the illustrated embodiment is a gas turbine 10. Although an industrial or land-based gas turbine is shown and described herein, the present disclosure is not limited to land-based and / or industrial gas turbines unless otherwise indicated in the claims. For example, the present invention as described herein can be used with any type of turbine, including but not limited to steam turbines, aircraft gas turbines, or marine gas turbines.

[0031] As shown, the gas turbine 10 generally includes an inlet section 12, a compressor 14 disposed downstream of the inlet section 12, a combustion section 16 disposed downstream of the compressor 14, a turbine 18 disposed downstream of the combustion section 16, and an exhaust section 20 disposed downstream of the turbine 18. Furthermore, the gas turbine 10 may include one or more shafts 22 coupling the compressor 14 to the turbine 18.

[0032] During operation, air 24 flows through the inlet section 12 and enters the compressor 14, where the air 24 is gradually compressed, thereby providing compressed air 26 to the combustion section 16. At least a portion of the compressed air 26 is mixed with fuel 28 within the combustion section 16 and combusted to produce combustion gases 30. From the combustion section 16, the combustion gases 30 flow into the turbine 18, where energy (kinetic energy and / or thermal energy) is transferred from the combustion gases 30 to rotor blades (not shown), thereby rotating the shaft 22. The mechanical rotational energy can then be used for various purposes, such as powering the compressor 14 and / or generating electricity. The combustion gases 30 exiting the turbine 18 can then be discharged from the gas turbine 10 via the exhaust section 20.

[0033] Figure 2 An upstream view of the combustion section 16 is provided according to various embodiments of the present disclosure. Figure 2 As shown, the combustion section 16 may be at least partially surrounded by an outer or compressor discharge casing 32. The compressor discharge casing 32 may at least partially define a high pressure chamber 34 that at least partially surrounds various components of the combustor 16. The high pressure chamber 34 may be connected to the compressor 14 ( Figure 1 ) is fluidly connected to receive compressed air 26 from the compressor. In various embodiments, as Figure 2 As shown, the combustion section 16 includes a segmented annular combustion system 36 including a plurality of combustors or integrated combustor nozzles 100 circumferentially arranged about an axial centerline 38 of the gas turbine 10 , which may coincide with the gas turbine shaft 22 .

[0034] Figure 3 A perspective view of the integrated burner nozzle 100 is provided as viewed from a first side. Figure 4A perspective view of an integrated burner nozzle 100 viewed from a second side is provided according to an embodiment of the present disclosure. Figure 2 、 Figure 3 and Figure 4 As shown collectively, the segmented annular combustion system 36 includes a plurality of integrated combustor nozzles 100. As further described herein, each combustor nozzle 100 includes a first sidewall 116 and a second sidewall 118. In a particular embodiment, the first sidewall is a pressure sidewall and the second sidewall is a suction sidewall based on the integration of the sidewalls with the corresponding pressure and suction sides of the downstream turbine nozzle 200. It should be understood that any reference herein to pressure and suction sidewalls represents a particular embodiment, such references are for convenience of discussion, and such references are not intended to limit the scope of any embodiment unless the specific context dictates otherwise.

[0035] like Figure 3 and Figure 4 As collectively shown, each combustor nozzle 100 includes an inner liner 106, an outer liner 108, and a hollow or semi-hollow combustion liner 110 extending between the inner liner 106 and the outer liner 108. It is contemplated that more than one (e.g., 2, 3, 4, or more) combustion liners 110 may be positioned between the inner liner 106 and the outer liner 108, thereby reducing the number of joints between adjacent liners that need to be sealed. For ease of discussion herein, reference will be made to an integrated combustor nozzle 100 having a single combustion liner 110 between the respective inner liner 106 and outer liner 108, although a 2:1 ratio of liners to combustion liners is not required. As Figure 3 and Figure 4 As shown, each combustion liner 110 includes a forward or upstream end portion 112 , an aft or downstream end portion 114 , a pressure sidewall 116 , and a suction sidewall 118 .

[0036] The segmented annular combustion system 36 also includes a fuel injection module 117. In the exemplary embodiment shown, the fuel injection module 117 includes a plurality of fuel nozzles. The fuel injection module 117 is configured to be installed in the forward end portion 112 of the corresponding combustion liner 110. For the purposes of this description, the fuel injection module 117 including the plurality of fuel nozzles may be referred to as a "bundle fuel nozzle." However, the fuel injection module 117 may include or comprise any type of fuel nozzle or combustor (such as a swirl fuel nozzle or a swirl nozzle), and unless specifically recited as such, the claims should not be limited to bundle fuel nozzles.

[0037] In at least one embodiment, Figure 3 and Figure 4As shown, the downstream end portion 114 of one or more of the combustion liners 110 transitions into a turbine nozzle 200 having an airfoil 202 that directs and accelerates the flow of combustion products toward the turbine blades. Thus, the downstream end portion 114 of each combustion liner 110 can be considered an airfoil without a leading edge. When the integrated combustor nozzle 100 is installed within the combustion section 16, the turbine nozzle 200 can be positioned immediately upstream of a stage of turbine rotor blades of the turbine 18.

[0038] As used herein, the term “integrated combustor nozzle” refers to a seamless structure that includes a combustion liner 110, a turbine nozzle 200 located downstream of the combustion liner 110, an inner liner 106 (embodied by the turbine nozzle 200) extending from a forward end 112 to an aft end 114 of the combustion liner 110, and an outer liner 108 (embodied by the turbine nozzle 200) extending from the forward end 112 to the aft end 114 of the combustion liner 110. In at least one embodiment, the turbine nozzle 200 of the integrated combustor nozzle 100 is used as a first-stage turbine nozzle and is positioned upstream of a first stage of turbine rotor blades.

[0039] To illustrate an example of an additive manufacturing system and process, Figure 5 A schematic / block diagram of an additive manufacturing system 1000 for producing a turbine component 1220 , such as the turbine nozzle 200 described herein, is shown. Figure 513. The additive manufacturing system 1000 may be configured for direct metal laser sintering (DMLS) or direct metal laser melting (DMLM). The additive manufacturing system 1000 manufactures an object, such as a turbine nozzle 200. For example, the object 1220 may be manufactured in a layer-by-layer manner by sintering or melting powder material in a powder bed 1120 using an energy beam 1360 generated by a source (such as a laser 1200). The powder to be melted by the energy beam is supplied from a reservoir 1260 and is evenly spread across the build plate 1002 using a recoater arm 1160 (which extends along a recoater direction 1340) to maintain the powder at a material level 1180 and remove excess powder material extending above the powder material level 1180 to a waste container 1280. The energy beam 1360, under the control of the galvanometer scanner 1320, sinters or melts the cross-sectional layers of the built object. Build plate 1002 is lowered, and another layer of powder is spread over the build plate and the constructed object, after which the powder is continuously melted / sintered by laser 1200. This process is repeated until object 1220 is completely constructed from the melted / sintered powder material. Laser 1200 can be controlled by a computer system including a processor and memory. The computer system can determine a scanning pattern for each layer and control laser 1200 to irradiate the powder material based on the scanning pattern. After the manufacture of object 1220 is completed, various post-processing procedures can be applied to object 1220. Post-processing procedures include removing excess powder by, for example, purging or vacuuming. Other post-processing procedures include stress relief processes. In addition, thermal post-processing procedures and chemical post-processing procedures can be used to finish object 1220.

[0040] Figure 6 and Figure 7 Two different perspective views of a turbine nozzle assembly 201 are shown, comprising a turbine nozzle 200 and a plurality of cooling fins 232 ( Figure 8 ). The turbine nozzle assembly is isolated from the various other components of the integrated combustor nozzle 100 and positioned on a build plate 1002. Turbine nozzle 200 may be additively manufactured on a build plate 1002, for example, via an additive manufacturing system 1000. For example, Figure 6 and Figure 7 Turbine nozzle 200 is depicted prior to removal from build plate 1002 and installation onto integrated combustor nozzle 100 , according to an embodiment of the present disclosure.

[0041] As shown, the turbine nozzle 200 may include an airfoil 202 extending from a build plate 1002. In many embodiments, the turbine nozzle may also include an inner liner segment 204 that is spaced apart from and disposed opposite an outer liner segment 206. As shown, the airfoil 202 may extend between the inner liner segment 204 and the outer liner segment 206. The airfoil 202 may have a generally aerodynamic profile that directs and accelerates the flow of combustion products toward the turbine blades. For example, the airfoil 202 may have a pressure sidewall 208 and a suction sidewall 210, each of which extends between a leading end 212 and a trailing edge 214 of the airfoil. As shown, the leading end 212 of the airfoil 202 may be fixedly coupled to the build plate 1002 during and immediately after the additive manufacturing process. Figure 3 and Figure 4 As shown, when the turbine nozzle 200 is installed in the integrated combustion nozzle 100, the pressure sidewall 208 may extend continuously with the pressure sidewall 116 of the combustion liner 110, and the suction sidewall 210 may extend continuously with the suction sidewall of the combustion liner 110. Similarly, when the turbine nozzle 200 is installed in the integrated combustion nozzle 100, the inner liner segment 204 may extend continuously with the inner liner 106, and the outer liner segment 206 may extend continuously with the outer liner segment 108.

[0042] In many embodiments, the turbine nozzle 200 may include one or more heat-sensitive portions 218 (e.g., Figure 6 and Figure 7 ). Heat-sensitive portion 218 may be one or more areas of turbine nozzle 200 that are susceptible to deformation and / or distortion due to the high heat of energy beam 1360 and the melting / sintering of powder during the additive manufacturing process. For example, heat-sensitive portion 218 of turbine nozzle 200 may not have a direct path between portion 218 and build plate 1002, leaving heat from the melting / sintering of powder nowhere to travel and / or dissipate. In this manner, if heat is not properly transferred, heat-sensitive portion 218 of turbine nozzle 200 may be susceptible to deformation and / or distortion caused by thermal stresses induced during the additive manufacturing process.

[0043] In many embodiments, both the pressure sidewall 208 and the suction sidewall 210 of the airfoil 202 can define a thermally sensitive portion 218. In particular embodiments, the thermally sensitive portion 218 can be provided only on the suction sidewall 208. As discussed below, the pressure sidewall 208 and the suction sidewall 210 of the airfoil 202 can each have a very small ratio of thickness 228, 230 to width 224, 222 and a ratio of thickness 228, 230 to height 226, i.e., the height 226 and width 224, 222 of the walls 208, 210 can be many times greater than the thickness 228, 230. In this manner, the walls 208, 210 are typically thinner and, therefore, more susceptible to deformation caused by thermal stresses during the additive manufacturing process.

[0044] For example, in many embodiments, the pressure sidewall 208 can include a thickness 228 to width 224 ratio between about 1% and about 10%. In other embodiments, the pressure sidewall can include a thickness 228 to width 224 ratio between about 1% and about 8%. In various embodiments, the pressure sidewall can include a thickness 228 to width 224 ratio between about 1% and about 5%. In an exemplary embodiment, the pressure sidewall can include a thickness 228 to width 224 ratio between about 2% and about 4%. Similarly, the suction sidewall 210 can include a thickness 230 to width 222 ratio between about 1% and about 10%. In other embodiments, the suction sidewall 210 can include a thickness 230 to width 222 ratio between about 1% and about 8%. In various embodiments, the suction sidewall 210 can include a thickness 230 to width 222 ratio between about 1% and about 5%. In an exemplary embodiment, the suction sidewall 210 may include a thickness 230 to width 222 ratio between approximately 2% and approximately 4%.

[0045] Likewise, in many embodiments, the pressure sidewall 208 and the suction sidewall 210 may each include a ratio of thickness 228, 230 to height 226 between about 0.5% and about 10%. In other embodiments, the pressure sidewall 208 and the suction sidewall 210 may each include a ratio of thickness 228, 230 to height 226 between about 0.5% and about 7%. In various embodiments, the pressure sidewall 208 and the suction sidewall 210 may each include a ratio of thickness 228, 230 to height 226 between about 0.7% and about 5%. In an exemplary embodiment, the pressure sidewall 208 and the suction sidewall 210 may each include a ratio of thickness 228, 230 to height 226 between about 1% and about 3%.

[0046] Figure 8 A cross-sectional view of turbine nozzle 200 is shown before removal from build plate 1002. Figure 8As shown, the turbine nozzle 200 may include ribs 220 extending between the pressure sidewall 208 and the suction sidewall 210 and between the inner liner section 204 and the outer inner liner section 206. In many embodiments, the ribs 220 may be substantially perpendicular to both the pressure sidewall 208 and the suction sidewall 210. The ribs 220 may be used to provide additional structural support to the airfoil 202 to prevent damage to the airfoil from vibration forces of the gas turbine 10 during operation. A plurality of cooling fins are configured to transfer heat away from heat-sensitive portions of the airfoil during the additive manufacturing process.

[0047] like Figure 8 As shown, turbine nozzle assembly 201 may include turbine nozzle 200 and a plurality of cooling fins 232. Fins 232 may be disposed within turbine nozzle 200. For example, fins 232 may extend between heat-sensitive portion 218 and ribs 220 to direct heat away from heat-sensitive portion 218 during the additive manufacturing process, thereby advantageously minimizing and / or preventing deformation or distortion of heat-sensitive portion 218. For example, in an exemplary embodiment, each of fins 232 may extend directly from suction sidewall 210 to ribs 220, thereby providing a means for heat from post-sintering or post-melting powder to travel from suction sidewall 210. In such an embodiment, fins 232 may indirectly transfer heat from heat-sensitive portion 218 to build plate 1002. In other embodiments (not shown), each fin 232 in plurality of fins 232 may extend directly from suction sidewall 210 to build plate 1002 , such that plurality of fins 232 may transfer heat from heat-sensitive portion 218 directly to build plate 1002 .

[0048] In many embodiments, such as Figure 8 As shown, the plurality of fins 232 can be arranged in linear rows spaced apart from one another between the pressure side wall 208 and the suction side wall 210, which advantageously provides heat transfer along the entire heat-sensitive portion 218 during the additive manufacturing process. As shown, in an exemplary embodiment, the plurality of fins 232 can be arranged in six linear rows, with each row spaced apart from the fins in the adjacent rows. However, in other embodiments, the plurality of fins can be arranged in more or fewer linear rows, depending on the size of the suction side wall 210. In various embodiments (not shown), the plurality of fins can be spaced apart from one another in the width direction (along the widths 222, 224 of the walls 208, 210). For example, Figure 8 The plurality of fins 232 shown may be arranged in the width direction of the wall (entering and exiting the wall) Figure 8 pages) are spaced apart from adjacent heat sinks.

[0049] In some embodiments, plurality of fins 232 may provide structural support for airfoil 202 during its manufacture. For example, in addition to providing a means for transferring heat during additive manufacturing of turbine nozzle 200, each of fins 232 may also provide structural support for various portions of airfoil 202, such as suction sidewall 210 and / or pressure sidewall 208. In this manner, fins 232 may advantageously prevent the presence of overhanging material during the additive manufacturing process, which could otherwise cause torque and / or complete collapse of the component. However, in other embodiments, fins 232 may simply be used to provide a means for transferring heat from heat-sensitive portion 218 to build plate 1002.

[0050] Figure 9 shows a first tooth end 234 of one of the plurality of fins 232 according to an embodiment of the present disclosure, and Figure 10 A second tooth end 236 of one of a plurality of heat sinks 232 is shown, according to an embodiment of the present disclosure. As shown, the first tooth end 234 can be fused to a heat-sensitive portion 218 of the airfoil 202 (such as a portion of the suction sidewall 210). Similarly, the second tooth end 236 can be fused to a second portion of the airfoil 202 or one of the build plates 1002. For example, in an exemplary embodiment, the second tooth end 236 can be fused to the rib 220. As shown, both the first tooth end 234 and the second tooth end 236 can include teeth 238 extending from the heat sink 232 and spaced apart from each other, which advantageously allows for a lower coupling force between the heat sink 232 and the airfoil 202. In this manner, the tooth ends 234, 236 advantageously facilitate removal of the heat sink 232 after the additive manufacturing process is completed. In many embodiments, the tooth ends 234, 236 allow for easy detachment of the heat sink 232 once the additive manufacturing process is complete.

[0051] Figure 11 1 is a flow chart of a set of sequential steps 1102 through 1106 that define a method 1100 for manufacturing a turbine nozzle 200 for a turbine using an additive manufacturing system, according to an embodiment of the present disclosure. The method 1100 may be performed using an additive manufacturing system, such as the additive manufacturing system 1000 described herein or another suitable system. Figure 11 As shown, method 1100 includes step 1102 of irradiating a powder layer in a powder bed 1120 to form a fusion region. In many embodiments, as Figure 5As shown, powder bed 1120 may be disposed on build plate 1002 such that the fusion region is fixedly attached to build plate 1002. Method 1100 may include step 1104 of providing a subsequent layer of powder on powder bed 1120 from a first side of powder bed 1120. Method 1100 also includes step 1106 of repeating steps 1102 and 1104 until turbine nozzle 200 and plurality of cooling fins 232 are formed in powder bed 1120. As discussed above, plurality of cooling fins 232 advantageously transfer heat away from heat sensitive portion 218 of airfoil 202, thereby preventing any deformation and / or distortion of heat sensitive portion 218. In this manner, cooling fins 232 allow turbine nozzle 200 to be manufactured using additive manufacturing system 1000 with minimal or no defects. As discussed above, plurality of cooling fins 232 advantageously transfer heat away from heat sensitive portion 218 of airfoil 202, thereby preventing any deformation and / or distortion of heat sensitive portion 218. In this manner, cooling fins 232 allow turbine nozzle 200 to be manufactured using additive manufacturing system 1000 with minimal or no defects. Figure 11 As shown, method 1100 may further include an optional step 1108 of removing airfoil 202 and plurality of cooling fins 232 from powder bed 1120 (e.g., removing turbine nozzle assembly 201 from build plate 1002) while airfoil 202 and plurality of cooling fins 232 are attached. Furthermore, in many embodiments, method 1100 may further include an optional step 1110 of removing plurality of cooling fins from airfoil 202. For example, once turbine nozzle assembly 201 is removed from build plate 1002, plurality of cooling fins 232 may be removed from turbine nozzle assembly 201, thereby forming a finished turbine nozzle 200.

[0052] Removal of fins 232 from airfoil 202 may occur immediately upon removal of turbine nozzle 200 from powder bed 1120, or during removal of the turbine nozzle from the powder bed. Alternatively, fins 232 may be removed after one or more post-processing steps have been performed on turbine nozzle 200. For example, turbine nozzle 200 and fins 232 may be subjected to a post-annealing process and / or chemical treatment and then subsequently removed from turbine nozzle 200.

[0053] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any combined methods. The patentable scope of the invention is defined by the claims and may include other examples that occur to those skilled in the art. If these other examples include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims, then these other examples are intended to be within the scope of the claims.

Claims

1. A method of manufacturing a turbine nozzle (200) for a turbine (10) using an additive manufacturing system (1000), the method comprising: irradiating a layer of powder in a powder bed (1120) to form a fused region, wherein the powder bed is disposed on a build plate (1002); providing a subsequent layer of powder on the powder bed (1120) by passing a recoater arm (1160) over the powder bed (1120) from a first side of the powder bed (1120); and The irradiating and providing steps are repeated until a turbine nozzle assembly (201) is formed on the build plate (1002), the turbine nozzle assembly (201) comprising the turbine nozzle (200) and a plurality of heat sinks (232) disposed within the turbine nozzle (200), wherein during the irradiating and providing steps the plurality of heat sinks (232) transfer heat from a heat-sensitive portion (218) of the turbine nozzle (200) directly to the build plate.

2. The method of claim 1 , wherein the turbine nozzle (200) includes an airfoil (202) extending between an outer liner section (206) and an inner liner section (204), and wherein the airfoil (202) includes a forward portion (212) fused to the build plate (1002), a trailing edge (214), a pressure sidewall (208), and a suction sidewall (210) extending between the forward portion (212) and the trailing edge (214).

3. The method of claim 2, wherein the heat-sensitive portion (218) of the airfoil (202) is a portion of the suction sidewall (210).

4. The method of claim 2, wherein the pressure sidewall (208) and the suction sidewall (210) each include a thickness (228, 230), a width (224, 222) defined between the outer liner section (206) and the inner liner section (204), and a ratio of thickness (228, 230) to width (224, 222) between about 1% and about 10%.

5. The method of claim 2, wherein the pressure sidewall (208) and the suction sidewall (210) each include a thickness (228, 230), a height (226) defined between the build plate (1002) and the trailing edge (214), and a ratio of thickness (228, 230) to height (226) between about 0.5% and about 10%.

6. The method of claim 1, further comprising removing the turbine nozzle assembly (201) from the build plate (1002) while the turbine nozzle (200) and the plurality of cooling fins (232) are connected.

7. The method of claim 6, further comprising removing the plurality of cooling fins (232) from the turbine nozzle assembly (201).

8. The method of claim 1 , wherein each of the plurality of cooling fins (232) includes a first tooth end fused to the heat-sensitive portion (218) of the turbine nozzle (200); and a second tooth end fused to one of a second portion of the turbine nozzle (200) or the build plate (1002).

9. The method of claim 1, wherein the plurality of fins (232) provide structural support for the turbine nozzle (200) during the illuminating and providing steps.

10. The method of claim 1, wherein the method is performed using direct metal laser sintering or direct metal laser melting.

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