Ceramic matrix composite components including counterflow channels and method for manufacturing them

Abstract

There is a need for ceramic matrix composite components and methods of manufacturing ceramic matrix composite components that provide improved cooling for CMC gas turbine components when subjected to extreme conditions such as extreme thermal gradients and high temperatures. A ceramic matrix composite (CMC) component and method of fabrication includes a plurality of counter-flow elongated functional features. The CMC component includes a plurality of longitudinally extending ceramic matrix composite plies forming a dense body and a plurality of elongated functional features formed within the dense body. Each of the plurality of functional features extends longitudinally and is configured to align with a plurality of ceramic matrix composite plies. Each of the plurality of elongated functional features includes an inlet configured in a transverse configuration across the plies. The plurality of elongated functional features are configured to deliver a fluid flow from a fluid source to an exterior of the ceramic matrix composite component. The plurality of functional features are configured in an alternating flow configuration.

Description

Technical Field

[0001] The present invention generally relates to a gas turbine for power generation, and more particularly, to a method for forming a ceramic matrix composite component for a high-temperature gas passage turbine component of a gas turbine.

Background Art

[0002] Silicon carbide (SiC)-based ceramic matrix composite (CMC) materials have been proposed as materials for specific components of gas turbine engines, such as turbine blades, vanes, nozzles, shrouds, and buckets. Various methods for fabricating SiC-based components are known, including Silicomp, melt infiltration (MI), chemical vapor infiltration (CVI), polymer infiltration pyrolysis (PIP), and oxide / oxide methods. These fabrication techniques are quite different from each other, but each involves the use of handling and tooling or dies to produce near-net shape parts through methods that include heating at various stages of the process.

[0003] Similar to turbine blades and vanes formed from more common superalloy materials, CMC blades, vanes, and shrouds typically have cavities and cooling passages primarily for component weight reduction, centrifugal load reduction, and operating temperature reduction. These features are typically formed in CMC components using a combination of removable and disposable tools, or perforation, etc. Internal cooling channels are advantageous for cooling both metal and CMC high-temperature gas passage hardware because they reduce cooling flow requirements and thermal gradients / stresses.

[0004] In many cases, CMC gas turbine components are subjected to extreme conditions in the form of extreme thermal gradients and high temperatures. Even if the CMC components have cavities or cooling vents as mentioned above, these extreme conditions can cause crack formation, coating fracture, and thinning of the CMC components. These problems shorten the operational life, preventing the CMC components from reaching their full potential. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] U.S. Patent No. 10,384,981 [Patent Document 2] The U.S. patent application is titled "Methods of Forming Ceramic Matrix Composites Using Sacrificial Fibers and Non-Wetting Coating" and is patent attorney processing number 328251-1. [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, there is a need for ceramic matrix composite components and methods for manufacturing ceramic matrix composite components that provide improved cooling to CMC gas turbine components when subjected to extreme conditions such as extreme thermal gradients and high temperatures. [Means for solving the problem]

[0007] The aspects and benefits of this disclosure are partially described in the following description, can be made apparent from that description, or can be learned through the implementation of this disclosure.

[0008] A ceramic matrix composite (CMC) component is provided as a whole, along with a method for forming the component. In one embodiment, the ceramic matrix composite component includes a plurality of longitudinally extending ceramic matrix composite plies forming a dense body, and a plurality of elongated functional feature portions formed within the dense body. Each of the plurality of functional feature portions extends longitudinally and is configured to be oriented with respect to the plurality of ceramic matrix composite plies. Each of the plurality of elongated functional feature portions includes at least one of an inlet configured in a cross-ply configuration and an outlet configured in a cross-ply configuration. The plurality of elongated functional feature portions are configured to supply a fluid flow from a fluid source to the outside of the ceramic matrix composite component. The plurality of functional feature portions are configured in an alternating flow configuration.

[0009] In an alternative embodiment, the ceramic matrix composite component includes a plurality of longitudinally extending ceramic matrix composite plies forming a dense body, a first plurality of cooling channels formed within the dense body and defining a fluid flow path for a fluid flowing backward from a fluid source to the outside of the ceramic matrix composite component, and a second plurality of cooling channels formed within the dense body and defining a fluid flow path for a fluid flowing forward from a fluid source to the outside of the ceramic matrix composite component. Each of the first plurality of cooling channels is configured to extend longitudinally in alignment with the plurality of ceramic matrix composite plies and to have an inlet configured to cross the plies. Each of the second plurality of cooling channels is configured to extend longitudinally in alignment with the plurality of ceramic matrix composite plies and to have an inlet configured to cross the plies. The first plurality of cooling channels and the second plurality of cooling channels are configured in an alternating flow configuration.

[0010] In yet another embodiment, a method for forming a ceramic matrix composite (CMC) product includes the steps of: forming a CMC preform comprising a matrix precursor, a plurality of reinforcing fibers, and a plurality of sacrificial fibers; performing one of the steps of removing one or more sacrificial fibers, or applying a fluid impregnating agent to the CMC preform, so that a plurality of elongated functional feature portions are formed along the CMC preform in a counter-flow configuration; and performing the other of the steps of removing one or more sacrificial fibers, or applying a fluid impregnating agent to the CMC preform, so that a plurality of elongated functional feature portions are formed along the CMC preform in a counter-flow configuration.

[0011] These and other features, aspects, and advantages of the Disclosure will be better understood by referring to the following description and the appended claims. The appended drawings are incorporated into and form part of this specification and serve to illustrate embodiments of the Disclosure and, together with this description, illustrate the principles of the Disclosure.

[0012] A complete and effective disclosure, including the best mode, is provided herein with reference to the accompanying drawings, intended for those skilled in the art. [Brief explanation of the drawing]

[0013] [Figure 1] This is a perspective view of a ceramic matrix composite (CMC) component, more particularly a portion of a CMC shroud, according to one or more embodiments disclosed herein. [Figure 2] This is a cross-sectional view of a portion of the shroud segment of Figure 1, viewed in the direction of 2-2 in Figure 1, according to one or more embodiments disclosed herein. [Figure 3] This is a cross-sectional view of a ceramic matrix composite (CMC) component of Figure 1, as seen in the direction of 3-3 in Figure 2, according to one or more embodiments disclosed herein. [Figure 4] This is a cross-sectional view of a ceramic matrix composite (CMC) component of Figure 1, as seen in the direction of 4-4 in Figure 2, according to one or more embodiments disclosed herein. [Figure 5] This is a schematic isometric view of a portion of another embodiment of a shroud segment according to one or more embodiments disclosed herein. [Figure 6] This is a cross-sectional view of a portion of another embodiment of the shroud segment according to one or more embodiments disclosed herein. [Figure 7] This is a cross-sectional view of a ceramic matrix composite (CMC) component according to one or more embodiments disclosed herein, as seen in the direction of 7-7 in Figure 6. [Figure 8] This is a cross-sectional view of a ceramic matrix composite (CMC) component according to one or more embodiments disclosed herein, as seen in the direction of 8-8 in Figure 6. [Figure 9] This is a schematic diagram of a method for forming a CMC component according to one or more embodiments disclosed herein. [Modes for carrying out the invention]

[0014] To the extent possible, use the same reference numerals to represent the same part throughout the drawing.

[0015] Embodiments of the present disclosure, compared to a concept that does not include one or more of the features disclosed herein, for example, enable the formation of multiple counterflow cooling channels in a CMC component, the channels being configured to be oriented with one or more CMC layers. The inclusion of counterflow cooling channels oriented with one or more CMC layers maintains the structural integrity of the component. The method according to the present disclosure has a more efficient cooling method that can reduce complexity at a lower cost and reduce the cooling requirements and cooling flow rates of the component.

[0016] When introducing elements of various embodiments of the present invention, the articles "a," "an," "the," and "said" are intended to mean that one or more of those elements exist. The terms "comprising," "including," and "having" are intended to include and also mean that there may be additional elements other than the recited elements. Next, reference is made in detail to embodiments of the present disclosure in which one or more examples are shown in the drawings. Each example is presented for the purpose of explaining the present disclosure and not for limiting the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and changes can be made to the present disclosure without departing from the scope or spirit of the present disclosure. For example, features illustrated or described as part of one embodiment can be used with another embodiment to result in further embodiments. Accordingly, it is intended that the present disclosure include such modifications and changes within the scope of the appended claims and their equivalents.

[0017] In the present disclosure, when a layer is described as being "on" or "over" another layer or substrate, it is understood that the layers can be in direct contact with each other or can have another layer or feature therebetween, unless explicitly stated otherwise. Thus, these terms merely describe the relative position of the layers with respect to each other, and since the relative position of above or below depends on the orientation of the device with respect to the viewer, these terms do not necessarily mean being "on top of."

[0018] Chemical elements are discussed in the present disclosure using their usual chemical abbreviations, such as those commonly found in the periodic table of the elements. For example, hydrogen is represented by its usual chemical abbreviation H, helium is represented by its usual chemical abbreviation He, and so on.

[0019] In this book, the "average particle diameter" or "average fiber diameter" refers to the diameter of particles or fibers such that about 50% of the particles or fibers have a diameter greater than that diameter and about 50% of the particles or fibers have a diameter less than that diameter.

[0020] In this book, "substantially" refers to at least about 90% or more of the stated group. For example, in this book, "substantially all" indicates that at least about 90% or more of each group has the property to which it applies, and "substantially none" or "substantially absent" indicates that at least about 90% or more of each group does not have the property to which it applies. In this book, "majority" refers to at least about 50% or more of the stated group. For example, in this book, "the majority of" indicates that at least about 50% or more of each group has the property to which it applies.

[0021] Ceramic matrix composite products ("CMC products"), particularly ceramic matrix composite products formed from melt infiltration, are provided in this book in their entirety along with methods of forming such products. The CMC products are formed from a plurality of ply layers that include a plurality of elongated functional features configured in a counterflow arrangement to enhance the function of the CMC, such as cooling channels within the CMC preform.

[0022] Systems used for power generation include, but are not limited to, gas turbines, steam turbines, and other turbine assemblies used for power generation, such as ground-based aerial turbines. In certain applications, power generation systems that include turbomachinery (e.g., turbines, compressors, and pumps) and other machinery may include components that are exposed to severe wear conditions. For example, certain power generation system components such as blades, buckets, casings, rotor wheels, shafts, shrouds, and nozzles may operate in high-temperature and / or high-speed environments. These components are manufactured using ceramic matrix composites, and these components may also include cooling passages. This disclosure provides CMC components that include multiple counterflow cooling passages or channels, and methods for forming ceramic matrix composite (CMC) components. Exemplary embodiments of this disclosure are shown in Figures 1 to 8 as part of a turbine shroud, but this disclosure is not limited to the illustrated structures.

[0023] Figure 1 is a perspective view of a component 10, such as a turbine shroud segment, though not limited to this. Figure 1 shows a turbine shroud segment 12, but other preferred components according to this disclosure include, but are not limited to, combustor liners, blades, nozzles, nozzle end walls, blade platforms, or other high-temperature gas passage components. The component 10 is preferably formed from a ceramic matrix composite (CMC) material. In this publication, ceramic matrix composite or "CMC" refers to a composite material comprising a ceramic matrix reinforced with ceramic fibers. Some examples of CMCs permissible in this publication include, but are not limited to, materials having a matrix and reinforcing fibers comprising oxides, carbides, nitrides, oxycarbides, oxynitrides, and mixtures thereof. Examples of non-oxide materials include, but are not limited to, CMC having a silicon carbide matrix and silicon carbide fibers (when produced by silicon melt impregnation, the matrix contains residual free silicon), CMC having a silicon carbide / silicon matrix mixture and silicon carbide fibers, CMC having a silicon nitride matrix and silicon carbide fibers, and CMC having a silicon carbide / silicon nitride matrix mixture and silicon carbide fibers. Furthermore, a CMC may have a matrix and reinforcing fibers made of oxide ceramics. In particular, oxide-oxide CMCs may consist of a matrix and reinforcing fibers containing oxide-based materials such as aluminum oxide (Al2O3), silicon dioxide (SiO2), aluminosilicates, and mixtures thereof. Therefore, in this book, the term "ceramic matrix composite" is not limited to carbon fiber reinforced carbon (C / C), carbon fiber reinforced silicon carbide (C / SiC), and silicon carbide fiber reinforced silicon carbide (SiC / SiC).In one embodiment, the ceramic matrix composite material exhibits improved ductility, fracture toughness, thermal shock, and anisotropy compared to an (unreinforced) monolithic ceramic structure.

[0024] Several methods can be used to fabricate SiC-SiC CMCs. In one method, the matrix is ​​partially formed or densified by molten impregnation (MI) of a CMC preform with molten silicon or silicon containing an alloy. In another method, the matrix is ​​at least partially formed by chemical vapor impregnation (CVI) of a CMC preform with silicon carbide. In a third method, the matrix is ​​at least partially formed by thermal decomposition of a preceramic polymer that becomes silicon carbide. This method is often referred to as polymer impregnation firing (PIP). The above three techniques can also be used in combination.

[0025] In one example of the MI CMC process, a boron nitride-based coating system is deposited onto SiC fibers. The coated fibers are then impregnated with a matrix precursor material to form a prepreg tape. One method of producing the tape is filament winding. The fibers are drawn through a bath of matrix precursor slurry, and the impregnated fibers are wound onto a drum. The matrix precursor can include silicon carbide and / or carbon nanoparticles, as well as organic materials. The impregnated fibers are then cut along the axis of the drum and removed from the drum to produce a flat prepreg tape in which the fibers are usually oriented in the same direction. The resulting material is a unidirectional prepreg tape. Prepreg tapes can also be made using a continuous prepreg machine or by other means. The tape is then cut into predetermined shapes, laid up, and laminated to produce a preform. The preform is pyrolysis or combustion to carbonize all organic material from the matrix precursor and to make it porous. Next, molten silicon is impregnated into the porous preform, where it can react with carbon to form silicon carbide. Ideally, excess free silicon fills all remaining pores, resulting in a high-density composite material. The matrix thus produced typically contains residual free silicon.

[0026] The prepreg MI process creates a material with a two-dimensional fiber structure where the fiber orientation changes between plies by stacking multiple one-dimensional prepreg plies on top of each other. Plies are often identified based on the continuous fiber orientation. A zero-degree orientation is established, and other plies are designed based on the angle of their fibers relative to the zero-degree direction. Plies in which the fibers extend perpendicular to the zero-degree direction are known as 90-degree plies, tolerance plies, or transverse plies.

[0027] MI techniques can also be used in two-dimensional or three-dimensional woven structures. An example of this technique is the slurry casting process, in which the fibers are first woven into a three-dimensional preform or a two-dimensional cloth. In the case of cloth, layers of cloth are cut into predetermined shapes and stacked to produce a preform. Chemical vapor impregnation (CVI) techniques are used to deposit interfacial coatings (typically boron nitride-based or carbon-based) onto the fibers. CVI can also be used to deposit layers of silicon carbide matrix. The remainder of the matrix is ​​formed by casting a matrix precursor slurry into the preform and then impregnating it with molten silicon.

[0028] An alternative to the MI method is to use CVI technology to densify silicon carbide matrices into one-dimensional, two-dimensional, or three-dimensional structures. Similarly, PIP can be used to densify the matrix of composite materials. Matrices produced by CVI and PIP can be produced without excess free silicon. Furthermore, MI, CVI, and PIP can be used in combination to densify matrices.

[0029] Multiple shroud segments 12 (of which only one is illustrated) define the shroud structure and are positioned concentrically with the rotor around which the turbine blades are attached. Generally, the shroud is produced in a ring shape, segmented, and then supplied to the end use as a set. As stated above, this disclosure is not intended to be limited to the specific shroud segments shown.

[0030] Each shroud segment 12 is generally made from multiple CMC plies (described shortly) and includes an arc-shaped shroud base 14 having axial components. A pair of upright ribs 18 and 20 are formed substantially perpendicular to the arc-shaped shroud base 14. The ribs 18 and 20 support the arc-shaped shroud base 14, and together they define cooling passages (described shortly) and chambers, such as chamber 22, within the shroud base 14. The ribs 18 and 20, and any optional flanges (not shown) included, help to mount the shroud segment 12 within the engine casing and mounting structure. Further cooling passages may be located on the ribs 18 and 20. During operation of the power generation system, a flow of cooling air (not shown) is directed through the cooling passages in the shroud base 14 to lower the temperature of the shroud segment 12.

[0031] Typically, in a gas turbine engine, multiple stationary shroud segments, generally similar to the shroud segment 12, are assembled circumferentially around the axis of the axial-flow engine and radially outward around a rotating blade member, such as a turbine blade, defining a portion of the flow path boundary radially outward of the blade. Furthermore, assemblies of shroud segments are assembled axially in the engine between axially adjacent engine members, such as a nozzle and / or engine frame. The stationary shrouds confine combustion gases to a gas flow path so as to utilize the combustion gases with maximum efficiency to drive the gas turbine. The operating temperature of this flow path can exceed 500°C. The shroud segment 12, including a surface 28 that defines the inner diameter, is exposed to a high-temperature gas flow path that flows from the front of the shroud segment, indicated as collectively by reference numeral 11, to the rear of the shroud segment, indicated as collectively by reference numeral 13, as shown by arrow 26 throughout the drawing.

[0032] Next, referring to Figures 2 to 4, partial cross-sectional views of component 10 in Figure 1 are shown. Figure 2 is a partial cross-sectional view of component 10 viewed in the direction of 2-2 in Figure 1. Figure 3 is a partial cross-sectional view of component 10 viewed in the direction of 3-3 in Figure 2. Figure 4 is a partial cross-sectional view of component 10 viewed in the direction of 4-4 in Figure 2. Multiple elongated functional feature portions 30, more specifically multiple cooling channels 32, formed on component 10 are shown in Figures 2 to 4. Multiple elongated functional feature portions 30 are defined within the CMC preform using multiple sacrificial fibers. The fabrication of elongated functional features using sacrificial fibers is discussed in U.S. Patent No. 10,384,981 by D. Hall et al., entitled “Methods of Forming Ceramic Matrix Composites Using Sacrificial Fibers and Related Products,” filed concurrently with this specification by D. Dunn et al., entitled “Methods of Forming Ceramic Matrix Composites Using Sacrificial Fibers and Non-Wetting Coating,” with attorney's approval number 328251-1, which is also incorporated herein by reference.

[0033] As mentioned above, component 10 consists of multiple ceramic matrix composite (CMC) plies 34 (Figures 3 and 4), only a few of which are shown for clarity. As shown in Figure 2, the functional feature section 30 is in fluid communication with a plenum (not shown) via multiple inlets (to be described shortly) and with the outside of component 10 via multiple outlets (to be described shortly). In an alternative embodiment, at least one of the multiple functional feature sections 30 may be in fluid communication with an alternative source of cooling fluid (not shown).

[0034] Referring more closely to Figure 2, a plurality of functional feature units 30, more specifically a plurality of cooling channels 32, are shown. Each of the plurality of cooling channels 32 includes an inlet 36 and an outlet 38. Each inlet 36 is in fluid communication with a cooling fluid source, such as a plenum (not shown) or an alternative source. Each outlet 38 is in fluid communication with the outside of the component 10.

[0035] Cooling fluid 40 flows through each cooling channel 32. As shown in the figure, the multiple cooling channels 32 are configured in a counter-flow configuration to supply cooling fluid 42 flowing forward and cooling fluid 44 flowing backward. More specifically, the cooling channels 32 are configured in an alternating configuration such that cooling channels 32 containing cooling fluid 42 flowing forward are adjacent to cooling channels 32 containing cooling fluid 44 flowing backward, and so that cooling channels 32 located next to each other have cooling fluids flowing in opposite or opposite directions.

[0036] As shown in Figure 2, the multiple cooling channels 32 are configured to include an inlet 36 for each of the first portions 32a of the multiple cooling channels 32 that contain the forward-flowing fluid 42. Furthermore, an inlet 36 is included for each of the second portions 32b of the multiple cooling channels 32 that contain the backward-flowing fluid 44. The inlets 36 for each of the third portions 32c of the multiple cooling channels 32 that contain the backward-flowing fluid 44 are located near the inlets 36 of each of the first portions 32a of the multiple cooling channels 32, so that the heat extraction from the fluid flow is distributed between the cooler-flowing fluid and the hotter-flowing fluid, thereby generating a more uniform temperature field. In this particular embodiment, the multiple cooling channels 32 are configured to include multiple long forward-flowing fluid channels 52 and multiple short backward-flowing fluid channels 56, as shown in Figure 3, and multiple long backward-flowing fluid channels 54, as shown in Figure 4.

[0037] As shown in Figures 3 and 4, each of the multiple cooling channels 32 is configured to be oriented with the multiple ceramic matrix composite (CMC) plies 34 in order to maintain the structural integrity of the component 10.

[0038] In the embodiments shown in Figures 2 to 4, the multiple cooling channels are aligned with the hot gas flow 26. In alternative embodiments, as shown in Figure 5, similar reference numerals are used to refer to the aforementioned elements, and the multiple functional feature units 30, more specifically the multiple cooling channels 32, are aligned perpendicular to the hot gas flow 26. The orientation of the cooling channels 32 relative to the hot gas flow 26 depends on the heat transfer requirements and external loads.

[0039] Next, referring to Figures 6 to 8, partial cross-sectional views of an alternative embodiment of component 50 that is generally similar to component 10 in Figure 1 are shown. Figure 6 is a partial cross-sectional view of a portion of the shroud segment of component 50, viewed in the same direction as in Figure 2. Figure 7 is a partial cross-sectional view of component 50, viewed in the direction of 7-7 in Figure 6. Figure 8 is a partial cross-sectional view of component 50, viewed in the direction of 8-8 in Figure 7. Unless otherwise noted, component 50 includes the same components as those identified in the description of component 10 in Figures 2 to 4. Multiple elongated functional feature sections 30, more specifically multiple cooling channels 32, formed on component 50 are shown in Figures 6 to 8. Similar to component 10, component 50 consists of multiple ceramic matrix composite (CMC) plies 34 (Figures 7 and 8), only a few of which are shown for clarity. As shown in Figure 6, the functional feature sections 30 are in fluid communication with the plenum (not shown) via multiple inlets (to be described shortly) and with the outside of component 50 via multiple outlets (to be described shortly). In an alternative embodiment, at least one of the multiple functional feature sections 30 may be in fluid communication with an alternative source of cooling fluid (not shown).

[0040] Referring more closely to Figure 6, a plurality of functional feature units 30, more specifically a plurality of cooling channels 32, are shown. Each of the plurality of cooling channels 32 includes an inlet 36 and an outlet 38. Each inlet 36 is in fluid communication with a cooling fluid source, such as a plenum (not shown) or an alternative source. Each outlet 38 is in fluid communication with the outside of the component 50.

[0041] Cooling fluid 40 flows through each cooling channel 32. As shown in the figure, the multiple cooling channels 32 are configured in a counter-flow configuration to supply cooling fluid 42 flowing forward and cooling fluid 44 flowing backward. More specifically, the cooling channels 32 are configured in an alternating configuration such that cooling channels 32 containing cooling fluid 42 flowing forward are adjacent to cooling channels 32 containing cooling fluid 44 flowing backward, and so that cooling channels 32 located next to each other have cooling fluids flowing in opposite or opposite directions.

[0042] As shown in Figure 6, the multiple cooling channels 32 are configured to include an inlet 36 for each of the first portions 32a of the multiple cooling channels 32 that contain the forward-flowing fluid 42. Furthermore, an inlet 36 is included for each of the second portions 32b of the multiple cooling channels 32 that contain the backward-flowing fluid 44. The inlets 36 for each of the third portions 32c of the multiple cooling channels 32 that contain the backward-flowing fluid 44 are located near the inlets 36 of each of the first portions 32a of the multiple cooling channels 32, so that the heat extraction from the fluid flow is distributed between the cooler-flowing fluid and the hotter-flowing fluid, thereby generating a more uniform temperature field. In this particular embodiment, the multiple cooling channels 32 are configured to include a long flow path 54 for the backward-flowing fluid, as shown in Figure 7, a long flow path 52 for the forward-flowing fluid, as shown in Figure 8, and a short flow path 56 for the backward-flowing fluid, as shown in Figures 7 and 8. In contrast to the embodiments shown in Figures 2 to 4, in this particular embodiment, the short flow path 56 for the fluid flowing backward is configured with an "over-under" design and further direction changes in order to increase its length and pressure drop.

[0043] In the embodiments shown in Figures 6 to 8, the multiple cooling channels are aligned with the hot gas flow 26. In an alternative embodiment, similar to Figure 5, the multiple functional features 30, more specifically the multiple cooling channels 32, are aligned perpendicular to the hot gas flow 26 depending on the heat transfer requirements and external load.

[0044] In the illustrated embodiments, the arrangement of the ceramic matrix composite ply 34 and the cooling channels 32 is schematic and enlarged for illustrative purposes. The size and shape of the cavities, such as the CMC ply 34 and the cooling channels 32, are not limited to those shown in Figures 2 to 8.

[0045] Figure 9 schematically illustrates a method 100 for forming CMC components 10, 50 according to this disclosure, which have a plurality of elongated functional feature portions 30, more specifically a plurality of counterflow cooling channels 32, arranged internally (see also Figures 2 to 8). Components 10, 50 are formed using a layup technique. Method 100 first includes the step of forming a CMC preform in step 102, which includes a matrix precursor, a plurality of ceramic reinforcing fibers, and a plurality of sacrificial fibers. The step of forming the CMC preform first includes preparing a ceramic matrix composite ply 34. The ceramic matrix composite ply 34 may be a single ply or a plurality of plies, such as a series of plies formed in a laminated stack. Examples of materials for the ply 34, but not limited to, as described above, include, for example, a prepreg composite ply containing carbon fiber fabric, a binder material, and coated SiC fibers.

[0046] As described above, the method, more specifically step 102 of forming the CMC preform, includes means for defining multiple functional feature portions internally, such as by using multiple sacrificial fibers. The sacrificial fibers enable the formation of one or more elongated functional feature portions 30 to enhance the function of the CMC, such as multiple counterflow cooling channels 32 within the CMC preform. The shape of the functional feature portions 30 defined within the CMC preform includes any suitable shape, including rounded, curved, elliptical, straight, or other suitable shapes.

[0047] Further plies 34 are arranged to surround the sacrificial fibers. The preform components are placed in an autoclave and an autoclave cycle is completed to form a CMC preform containing matrix precursors, multiple ceramic reinforcing fibers, and multiple sacrificial fibers. The preform components undergo typical autoclave pressure and temperature cycles used in ceramic composite materials in the industry. Autoclave treatment extracts any volatile substances remaining in the plies, and autoclave conditions can be varied depending on the ply material. After autoclave treatment, a burnout process is performed to remove any remaining material or further binders in the preform components. The burnout process is generally performed at temperatures of approximately 426–648°C (approximately 800–1200°F).

[0048] After burnout, in step 104, the preform components are placed in a vacuum furnace for densification. Densification is carried out using any known densification technique, including, but not limited to, Silicomp, molten impregnation (MI), chemical vapor impregnation (CVI), polymer impregnation firing (PIP), and oxide / oxide methods. Densification can be carried out in a vacuum furnace in an established atmosphere at a temperature above 1200°C so that silicon or other impregnation material can be molten impregnated into the preform components. One preferred densification method is molten impregnation, in which case the molten matrix material can be drawn into the ply 34 and solidified. After densification, the densified preform components or dense bodies contain a plurality of sacrificial fibers positioned inside, as shown in step 204, forming at least a portion of components 10, 50.

[0049] Following densification, the multiple functional feature portions 30 are further formed in step 106 by removing sacrificial fibers to define counterflow cooling channels 32, leaving a plurality of elongated channels behind. Removing sacrificial fibers to form elongated channels is discussed in U.S. Patent Application No. 10,384,981 and PTA Proceedings No. 328251-1, which are the same applicant and assignee as referenced above.

[0050] In an alternative embodiment, the multiple functional feature portions 30 are further formed by removing multiple sacrificial fibers before densification as described in step 104, leaving multiple counterflow cooling channels 32 behind.

[0051] In one embodiment, the internal hollow portion of each of the multiple functional feature sections 30 is sufficiently large and open within the components 10, 50 to allow a coolant or other fluid to pass through the components 10, 50 and cool them. However, the densified matrix material formed in the ceramic matrix composite ply 34 may form a sealing portion that substantially obstructs the flow of the coolant or other fluid, and more specifically, the functional feature section 30 forms a closed structure inside the components 10, 50. In one embodiment, openings are machined or otherwise formed in the components 10, 50 to provide an inlet 36 and / or outlet 38 for each of the functional feature sections 30 so that one or more elongated functional feature sections 30 can flow through them.

[0052] While the present invention has been described with reference to one or more embodiments, it will be understood by those skilled in the art that various modifications can be made without departing from the scope of the invention, and that equivalents can be substituted for elements of the invention. Furthermore, many modifications can be made to adapt the teachings of the invention to specific situations or materials without departing from the essential scope of the invention. Thus, the invention is not limited to the specific embodiments disclosed as the best possible mode for carrying out the invention, but is intended to include all embodiments that fall within the scope of the appended claims.

[0053] Further aspects of the present invention are presented by the subject matter of the following sections.

[0054] [Section 1] A ceramic matrix composite component, Multiple longitudinally extending ceramic matrix composite plies form a dense body, A plurality of elongated functional feature portions formed within a dense body, each of which extends in the longitudinal direction and is configured to be oriented with respect to a plurality of ceramic matrix composite plies, each of which includes at least one of an inlet configured to cross the plies and an outlet configured to cross the plies, the plurality of elongated functional feature portions are configured to supply fluid flow from a fluid source to the outside of the ceramic matrix composite component, and the plurality of functional feature portions are configured in an alternating flow configuration, and A ceramic matrix composite component comprising the same features.

[0055] [Section 2] A ceramic matrix composite component as described in any of the preceding sections, wherein multiple elongated functional feature portions are surrounded within a dense body.

[0056] [Section 3] A ceramic matrix composite component according to any of the preceding sections, wherein multiple elongated functional feature portions include multiple counterflow cooling channels.

[0057] [Section 4] A ceramic matrix composite component according to any of the preceding items, wherein multiple counterflow cooling channels extend longitudinally from front to back with respect to the high-temperature gas passage flow.

[0058] [Section 5] A ceramic matrix composite component according to any of the preceding items, wherein multiple counterflow cooling channels define multiple forward-flowing fluid channels and multiple backward-flowing fluid channels in an alternating configuration.

[0059] [Section 6] A ceramic matrix composite component as described in any of the preceding items, wherein a first portion of the plurality of cooling channels contains a forward-flowing fluid contained therein, a second portion of the plurality of cooling channels contains a rear-flowing fluid contained therein, and a third portion of the plurality of cooling channels contains a rear-flowing fluid contained therein, and the inlet of the first portion of the plurality of cooling channels is positioned near the inlet of the third portion of the plurality of cooling channels so that the heat extraction of the fluid flow is distributed between the cooler fluid and the hotter fluid.

[0060] [Section 7] A ceramic matrix composite component as described in any of the preceding sections, wherein the third portion of the multiple cooling channels is configured to have an up-down design and multiple direction changes in order to lengthen the length of the multiple rearward-flowing fluid passages and to increase the pressure drop of the rearward-flowing fluid contained within.

[0061] [Section 8] A ceramic matrix composite component, as described in any of the preceding items, which is a component of a high-temperature gas passage turbine.

[0062] [Section 9] A ceramic matrix composite component as described in any of the preceding sections, wherein the high-temperature gas passage turbine component is selected from the group consisting of combustor liners, blades, shrouds, nozzles, nozzle end walls, and blade platforms.

[0063] [Section 10] A ceramic matrix composite component, Multiple longitudinally extending ceramic matrix composite plies form a dense body, A first plurality of cooling channels formed within a dense body, defining a fluid flow path from a fluid source to the outside of the ceramic matrix composite component, wherein each of the first plurality of cooling channels has an inlet configured to extend longitudinally in alignment with the plurality of ceramic matrix composite plies and to cross the plies, A second plurality of cooling channels formed within a dense body, defining a fluid flow path from a fluid source to the outside of the ceramic matrix composite component, wherein each of the second plurality of cooling channels has an inlet configured to extend longitudinally in alignment with the plurality of ceramic matrix composite plies and to cross the plies. Equipped with, The first set of multiple cooling channels and the second set of multiple cooling channels are configured in an alternating flow configuration. Ceramic matrix composite component.

[0064] [Section 11] A ceramic matrix composite component as described in any of the preceding sections, wherein multiple cooling channels are surrounded within a dense body.

[0065] [Section 12] A ceramic matrix composite component as described in any of the preceding sections, wherein each of the first plurality of cooling channels and the second plurality of cooling channels further includes a fluid outlet.

[0066] [Section 13] A ceramic matrix composite component as described in any of the preceding items, wherein a first portion of the plurality of cooling channels contains a forward-flowing fluid contained therein, a second portion of the plurality of cooling channels contains a rear-flowing fluid contained therein, and a third portion of the plurality of cooling channels contains a rear-flowing fluid contained therein, and the inlet of the first portion of the plurality of cooling channels is positioned near the inlet of the third portion of the plurality of cooling channels so that the heat extraction of the fluid flow is distributed between the cooler fluid and the hotter fluid.

[0067] [Section 14] A ceramic matrix composite component as described in any of the preceding sections, wherein the third portion of the multiple cooling channels is configured to have an up-down design and multiple direction changes in order to lengthen the length of the multiple rearward-flowing fluid passages and to increase the pressure drop of the rearward-flowing fluid contained within.

[0068] [Section 15] A ceramic matrix composite component, as described in any of the preceding items, which is a component of a high-temperature gas passage turbine.

[0069] [Section 16] A ceramic matrix composite component as described in any of the preceding sections, wherein the high-temperature gas passage turbine component is selected from the group consisting of combustor liners, blades, shrouds, nozzles, nozzle end walls, and blade platforms.

[0070] [Section 17] A method for forming ceramic matrix composite (CMC) products, A step of forming a CMC preform comprising a matrix precursor, multiple reinforcing fibers, and multiple sacrificial fibers, The steps include removing one or more sacrificial fibers so that multiple elongated functional feature portions are formed in a counterflow configuration along the CMC preform, or A step of applying a fluid impregnating agent to a CMC preform, thereby densifying the CMC preform. A step of performing one of the following, The steps include removing one or more sacrificial fibers so that multiple elongated functional feature portions are formed in a counterflow configuration along the CMC preform, or A step of applying a fluid impregnating agent to a CMC preform, thereby densifying the CMC preform. The step of performing the other of the two A method that includes this.

[0071] [Section 18] The method according to any of the preceding items, wherein multiple elongated functional feature portions are provided with multiple counterflow cooling channels.

[0072] [Section 19] The method according to any of the preceding terms, wherein multiple counterflow cooling channels define multiple forward-flowing fluid channels and multiple backward-flowing fluid channels in an alternating configuration.

[0073] [Section 20] The method according to any of the preceding items, wherein the ceramic matrix composite component is a high-temperature gas passage turbine component. [Explanation of symbols]

[0074] 10 Components 11. Front of the shroud segment 12 Turbine Shroud Segments 13 Rear of the shroud segment 14 Shroud base 18 Ribs 20 Ribs 22 Chambers 26 High-temperature gas flow 28 Surface 30 Functional Features Section 32 cooling channels 32a First part of the cooling channel 32b Second part of the cooling channel Third part of the 32c cooling channel 34 Ceramic Matrix Composite (CMC) Ply 36 Entrance 38 Exit 40 Cooling fluid 42 Cooling fluid flowing forward 44 Cooling fluid flowing to the rear 50 components 52 Long channel for fluid flowing forward 54 Long flow path for fluid flowing backward 100 ways

Claims

1. A ceramic matrix composite component, Multiple longitudinally extending ceramic matrix composite plies form a dense body, It comprises multiple elongated functional feature parts formed within a dense body, Each of the multiple elongated functional feature portions extends in the longitudinal direction and is configured to be oriented in the same direction as the multiple longitudinally extending ceramic matrix composite material plies, and includes a portion that is positioned between two adjacent plies of the multiple longitudinally extending ceramic matrix composite material plies and is directly adjacent to the two adjacent plies. Each of the plurality of elongated functional feature portions includes at least one of an inlet configured to cross the ply and an outlet configured to cross the ply, and the plurality of elongated functional feature portions is configured to supply a fluid flow from a fluid source to the outside of the ceramic matrix composite component, and the plurality of elongated functional feature portions includes a plurality of counterflow cooling channels, The plurality of elongated functional features are configured in an alternating flow configuration such that a cooling channel configured to allow cooling fluid to flow forward is adjacent to another cooling channel configured to allow cooling fluid to flow backward, and the cooling channels located next to each other are configured to allow cooling fluid to flow in opposite directions. A ceramic matrix composite component in which the plurality of counterflow cooling channels are oriented perpendicular to the high-temperature gas flow to which the ceramic matrix composite component is exposed.

2. A ceramic matrix composite component according to claim 1, wherein multiple elongated functional feature portions are surrounded within a dense body.

3. The ceramic matrix composite component according to claim 1, wherein a plurality of counterflow cooling channels alternately define a plurality of forward-flowing fluid channels and a plurality of backward-flowing fluid channels.

4. A ceramic matrix composite component according to claim 1, wherein a first portion of a plurality of elongated functional feature portions contains a forward-flowing fluid contained within, a second portion of a plurality of elongated functional feature portions contains a rear-flowing fluid contained within, and a third portion of a plurality of elongated functional feature portions contains a rear-flowing fluid contained within, and the inlet of the first portion of the plurality of elongated functional feature portions is positioned near the inlet of the third portion of the plurality of elongated functional feature portions so that the heat extraction from the fluid flow is distributed between the cooler fluid and the hotter fluid.

5. A ceramic matrix composite component according to claim 1, which is a component of a high-temperature gas passage turbine.

6. The ceramic matrix composite component according to claim 5, wherein the high-temperature gas passage turbine component is selected from the group consisting of a combustor liner, blades, shrouds, nozzles, nozzle end walls, and blade platforms.

7. A ceramic matrix composite component, Multiple longitudinally extending ceramic matrix composite plies form a dense body, A first plurality of cooling channels formed within a dense body, defining a fluid flow path from a fluid source to the outside of a ceramic matrix composite component, wherein each of the first plurality of cooling channels is configured to extend longitudinally in alignment with the plurality of longitudinally extending ceramic matrix composite plies, and comprises a portion located between two adjacent plies of the plurality of longitudinally extending ceramic matrix composite plies and directly adjacent to the two adjacent plies, and each of the first plurality of cooling channels has an inlet configured to cross the plies, A second plurality of cooling channels formed within a dense body, defining a fluid flow path from a fluid source to the outside of a ceramic matrix composite component, wherein each of the second plurality of cooling channels is configured to extend longitudinally in alignment with the plurality of longitudinally extending ceramic matrix composite plies, and has an inlet configured to cross the plies, having a portion positioned between two adjacent plies of the plurality of longitudinally extending ceramic matrix composite plies and directly adjacent to the two adjacent plies. Equipped with, A plurality of first and second cooling channels are configured in an alternating flow configuration such that a cooling channel configured to allow cooling fluid to flow forward is adjacent to another cooling channel configured to allow cooling fluid to flow backward, and cooling channels located next to each other are configured to allow cooling fluid to flow in opposite directions. A ceramic matrix composite component in which the first plurality of cooling channels and the second plurality of cooling channels are oriented perpendicular to the high-temperature gas flow to which the ceramic matrix composite component is exposed.

8. The ceramic matrix composite component according to claim 7, wherein the first plurality of cooling channels and the second plurality of cooling channels are surrounded within a dense body.

9. The ceramic matrix composite component according to claim 7, wherein each of the first plurality of cooling channels and the second plurality of cooling channels further includes a fluid outlet.

10. A ceramic matrix composite component according to claim 7, wherein the first portion of the first plurality of cooling channels contains a forward-flowing fluid contained therein, the second portion of the second plurality of cooling channels contains a rear-flowing fluid contained therein, and the third portion of the second plurality of cooling channels contains a rear-flowing fluid contained therein, and the inlet of the first portion of the first plurality of cooling channels is positioned near the inlet of the third portion of the second plurality of cooling channels so that the heat extraction of the fluid flow is distributed between the cooler fluid and the hotter fluid.

11. A ceramic matrix composite component according to claim 7, which is a component of a high-temperature gas passage turbine.

12. The ceramic matrix composite component according to claim 11, wherein the high-temperature gas passage turbine component is selected from the group consisting of a combustor liner, blades, shrouds, nozzles, nozzle end walls, and blade platforms.

13. A method for forming ceramic matrix composite (CMC) products, A step of forming a CMC preform comprising a matrix precursor, a plurality of longitudinally extending reinforcing fibers, and a plurality of sacrificial fibers, wherein each of the plurality of sacrificial fibers is positioned between two adjacent reinforcing fibers of the plurality of longitudinally extending reinforcing fibers and has portions directly adjacent to the two adjacent reinforcing fibers, The steps include removing the multiple sacrificial fibers so that multiple elongated functional feature portions are formed in a counter-flow configuration along the CMC preform, or A step of applying a fluid impregnating agent to a CMC preform, thereby densifying the CMC preform. A step of performing one of the following, The steps include removing the multiple sacrificial fibers so that multiple elongated functional feature portions are formed in a counter-flow configuration along the CMC preform, or A step of applying a fluid impregnating agent to a CMC preform, thereby densifying the CMC preform. The step of performing the other of the two Includes, The plurality of elongated functional feature portions include a plurality of counterflow cooling channels. The plurality of elongated functional features are configured in an alternating flow configuration such that a cooling channel configured to allow cooling fluid to flow forward is adjacent to another cooling channel configured to allow cooling fluid to flow backward, and the cooling channels located next to each other are configured to allow cooling fluid to flow in opposite directions. A method in which the plurality of counterflow cooling channels are oriented perpendicular to the high-temperature gas flow to which the ceramic matrix composite product is exposed.

14. The method according to claim 13, wherein a plurality of counterflow cooling channels define a plurality of forward-flowing fluid channels and a plurality of backward-flowing fluid channels in an alternating configuration.

15. The method according to claim 13, wherein the CMC product is a component of a high-temperature gas passage turbine.

16. The ceramic matrix composite component according to claim 1, wherein each portion of the plurality of elongated functional feature portions, which is positioned between two adjacent prices of the plurality of longitudinally extending ceramic matrix composite prices and is directly adjacent to the two adjacent prices, is positioned between two adjacent prices of the plurality of longitudinally extending ceramic matrix composite prices and is in contact with the two adjacent prices along the entire length of the portion.

17. The ceramic matrix composite component according to claim 7, wherein the portion of the first plurality of cooling channels, which is positioned between two adjacent plies of the plurality of longitudinally extending ceramic matrix composite plies and is directly adjacent to the two adjacent plies, is positioned between two adjacent plies of the plurality of longitudinally extending ceramic matrix composite plies and is in contact with the two adjacent plies.

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