System and method for repairing engine multi-layer components

Abstract

A method of in-module repair of a multi-layer component of an engine includes identifying a location of damage on the multi-layer component. The damaged position at least partially extends into the ceramic top layer of the multi-layer component; the method further includes depositing a material composition onto the damaged location at a first temperature range to cover the damaged location. The material composition comprises more than one sintering additive. In addition, the method includes applying a local cure to the material composition deposited at the damage location at a second temperature range, the second temperature range being higher than the first temperature range.

Description

Priority information

[0001] This application claims priority based on Indian patent application serial number 202311058478 filed on August 31, 2023. Technical Field

[0002] The present invention relates generally to gas turbine engines and, more particularly, to systems and methods for repairing multi-layered components of engines, such as seal teeth. Background Art

[0003] At least some gas turbine engines (e.g., turbofan engines) include a fan and a core engine that drives the fan. The core engine includes at least one compressor, a combustor, and a high-pressure turbine that are connected in series in sequence. More specifically, the compressor and the high-pressure turbine are connected by a first drive shaft to form a high-pressure rotor assembly. The air entering the core engine is mixed with fuel and ignited to form a high-energy gas flow. The high-energy gas flow flows through the high-pressure turbine, rotationally driving the high-pressure turbine so that the first drive shaft rotationally drives the compressor. The gas flow expands when it flows through a low-pressure turbine disposed at the rear of the high-pressure turbine. The low-pressure turbine includes a rotor assembly connected to a second drive shaft, and the second drive shaft is connected to the fan. The low-pressure turbine rotationally drives the fan through the second drive shaft.

[0004] Some turbines and compressors include multiple stages. Multi-stage turbines and compressors typically include interstage seals disposed between adjacent stages. Interstage seals prevent leakage of gas compressed or expanded by the previous stage. Specifically, an interstage seal may be disposed between two rotating disks to provide a fluid seal therebetween to prevent or limit leakage through the rotating disks. Common interstage seals may have a generally annular configuration having a plurality of sealing teeth disposed on a sealing ring to prevent interstage leakage. Aircraft engines having gas turbine engines may use a similar design.

[0005] However, such interstage seals may have maintainability and reliability issues. For example, uneven temperature distribution during operation may cause relatively large tensile forces therein. In addition, during service, the top layer may peel off due to a variety of reasons. Once peeling exceeding a critical size occurs during operation, the only option is to replace and repair the entire component by stripping and recoating. Therefore, the repair of the seal teeth can only be done at the component level by disassembling the engine. Summary of the invention

[0006] The present invention provides a method for repairing a multi-layer engine component within a module, the method comprising: identifying a damaged location on a multi-layer component having at least one defect, wherein the at least one defect at least partially extends into a ceramic top layer of the multi-layer component; depositing a material composition onto the damaged location under a first temperature range to cover the damaged location, the material composition comprising more than one sintering additive; and applying local curing to the material composition deposited at the damaged location under a second temperature range, the second temperature range being higher than the first temperature range.

[0007] The present invention also provides a system for repairing the ceramic top layer of a multi-layer component of an engine within a module, the system comprising: a material composition for covering defects at a damaged location of the ceramic top layer, the material composition comprising a sintering additive and a nucleating agent; and a heat source, the heat source being used to apply local heat to the material composition at the damaged location to solidify the material composition, the sintering additive being converted into a crystalline phase during the treatment process to restore the toughness of the ceramic top layer of the multi-layer component after repair, and the nucleating agent converting the sintering additive into a ceramic material to reduce the brittleness of the repaired multi-layer component. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The specification describes the present invention including its best mode in conjunction with the accompanying drawings, providing a complete and implementable disclosure to those skilled in the art, wherein:

[0009] Figure 1 Schematic cross-sectional views of gas turbine engines according to various embodiments of the present invention.

[0010] Figure 2 for Figure 1 A detailed view of a compressor of a gas turbine engine of the present invention, particularly showing an exemplary location of a seal of the present invention;

[0011] Figure 3 for Figure 2 A simplified partial diagram of a compressor of a gas turbine engine;

[0012] Figure 4 A detailed view of an embodiment of a sealing tooth of the present invention;

[0013] Figure 5 A flow chart of an embodiment of a method for repairing a multi-layer engine component according to the present invention;

[0014] Figures 6A-6E is a schematic diagram of the operational sequence of an embodiment of a system for repairing a multi-layered engine component. DETAILED DESCRIPTION

[0015] Embodiments of the present invention are described in detail below, and one or more examples of the present invention are shown in the accompanying drawings. Examples are provided to explain rather than limit the present invention. In fact, it is obvious to those skilled in the art that various modifications and variations may be made to the present invention without departing from the scope or spirit of the present invention. For example, a feature shown or described as part of one embodiment may be used together with another embodiment to produce another embodiment. Therefore, this means that the present invention encompasses such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0016] As used herein, the word "exemplary" means "serving as an example, instance, or illustration." An embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. In addition, unless expressly stated otherwise, all embodiments described herein should be considered exemplary.

[0017] The singular forms "a", "an" and "the" include plural forms unless the context clearly dictates otherwise.

[0018] In a context such as “at least one of A, B, and C,” the term “at least one of” means only A, only B, only C, or any combination of A, B, and C.

[0019] The term "turbomachine" refers to a machine that includes one or more compressors, a heat generating portion (eg, a combustion portion), and one or more turbines that together produce a torque output.

[0020] The term "gas turbine engine" refers to an engine having turbomachinery as all or part of its power source. Exemplary gas turbine engines include turbofan engines, turboprop engines, turbojets, turboshaft engines, etc., as well as hybrid electric versions of one or more of these engines.

[0021] The term "combustion section" refers to a heat supply system of a turbomachine. For example, the term combustion section may refer to a section including one or more of a deflagration combustion assembly, a rotating detonation combustion assembly, a pulse detonation combustion assembly, or other suitable heat supply assemblies. In certain example embodiments, the combustion section may include an annular combustor, a can combustor, a tube combustor, a trapped vortex combustor (TVC), or other suitable combustion systems, or combinations thereof.

[0022] As used herein, the term "rotor" refers to a component of a rotating machine (eg, a turbine engine) that rotates about an axis of rotation. For example, a rotor may include a shaft or spool of a rotating machine (eg, a turbine engine).

[0023] As used herein, the term "stator" refers to a component of a rotating machine (e.g., a turbine engine) that is disposed and arranged coaxially with a rotor of the rotating machine. The stator may be disposed radially inwardly or radially outwardly along a radial axis relative to at least a portion of the rotor. Additionally, or alternatively, the stator may be disposed axially adjacent to at least a portion of the rotor.

[0024] When used with reference to a compressor, turbine, shaft or shaft component, etc., unless otherwise indicated, the terms "low" and "high" or their respective comparatives (e.g., "lower", "more", as applicable) each refer to relative speeds within the engine. For example, a "low turbine" or "low-speed turbine" defines a component that is configured to operate at a lower rotational speed (e.g., maximum allowable rotational speed) than a "high turbine" or "high-speed turbine" of the engine.

[0025] The terms "front" and "rear" refer to relative positions within a gas turbine engine or vehicle and refer to the normal operating attitude of the gas turbine engine or vehicle. For example, for a gas turbine engine, "front" refers to a position closer to the engine inlet, while "rear" refers to a position closer to the engine nozzle or exhaust.

[0026] The terms "upstream" and "downstream" refer to the relative directions of fluid flow in a fluid path. For example, "upstream" refers to the direction from which the fluid flows, and "downstream" refers to the direction to which the fluid flows.

[0027] As used herein, the terms "axial" and "axially" refer to directions and orientations extending substantially parallel to the centerline of the gas turbine engine. Additionally, the terms "radial" and "radially" refer to directions and orientations extending substantially perpendicular to the centerline of the gas turbine engine. Additionally, as used herein, the terms "circumferential" and "circumferentially" refer to directions and orientations extending in an arc around the centerline of the gas turbine engine.

[0028] Unless otherwise specified herein, the terms “coupled,” “fixed,” “attached,” and the like refer to both direct coupling, fixing, or attachment as well as indirect coupling, fixing, or attachment via one or more intermediate components or features.

[0029] Herein, the terms “first”, “second”, “third”, etc. may be used interchangeably to distinguish one component from another, and are not intended to indicate the position or importance of each component.

[0030] The term "adjacent" as used herein with respect to two walls and / or surfaces refers to two walls and / or surfaces that are in contact with each other, or two walls and / or surfaces that are separated only by one or more non-structural layers and the two walls and / or surfaces are in series contact with the one or more non-structural layers (i.e., a first wall / surface contacts one or more non-structural layers, which in turn contact a second wall / surface).

[0031] The approximate expressions used in the specification and claims of this application are used to modify quantitative expressions, which allow changes without causing changes in the basic functions associated with them. Therefore, the values ​​modified by terms such as "about", "approximately" and "substantially" are not limited to the exact values ​​listed. In at least some cases, the approximate expressions can correspond to the accuracy of the instrument used to measure the relevant values ​​or the accuracy of the method or machine used to construct or manufacture parts and / or systems. For example, the approximate expression can refer to an amplitude of 1%, 2%, 4%, 10%, 15% or 20%. These approximate amplitudes can be applied to a single value, define any end point or two end points of a numerical range, and / or the amplitude of the range between the end points.

[0032] Here and throughout the specification and claims, range limitations are combined and interchanged, and unless context or language indicates otherwise, these ranges are defined to include all sub-ranges contained therein. For example, all ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other.

[0033] An exemplary aspect of the present invention relates to a system and method for repairing gas turbine engine components (e.g., seal teeth) using a unique material composition. As described above, multi-stage turbines and compressors typically include interstage seals disposed between each stage to prevent leakage of gas compressed by the previous stage. Specifically, the interstage seal may be located between two rotating disks for providing a fluid seal therebetween to prevent or limit leakage through the rotating disks. Common interstage seals may have a generally annular configuration with a plurality of seal teeth disposed on a sealing ring for preventing interstage leakage. The seal teeth typically have three layers, such as a base layer, an intermediate layer, and a ceramic top layer. The base layer is typically a nickel-based alloy or a titanium-based alloy. The intermediate layer is typically a nickel-aluminide bond coat. The ceramic top layer is typically made of aluminum oxide. For certain seal teeth, the intermediate layer and the ceramic top layer may be deposited onto the base layer using any suitable application method, such as by atmospheric plasma spraying (APS), additive manufacturing, and the like.

[0034] During operation of the gas turbine engine, such interstage seals experience uneven temperature distribution, which may affect the integrity of the seal and / or the seal teeth. In addition, during the service life of the engine, the ceramic top layer may spall due to a variety of reasons, including but not limited to fracture due to static contact loads during disassembly, Hastelloy metal transfer and / or cracks formed in the ceramic top layer during turning operations when the original equipment manufacturer (OEM) manufactures the components. As used herein, "spalling" generally refers to the process by which material fragments break away from the body due to stress. Once spalling exceeds a critical size during operation, the only option is to replace and repair the entire component by stripping and recoating. Typically, repair of the seal teeth can only be accomplished at the component level by disassembling the engine.

[0035] Thus, the present invention relates to new material compositions for repairing gas turbine engine components, such as seal teeth, and methods of using the material compositions in-module (i.e., when the seal teeth are installed in the engine) and / or when the engine is disassembled. More specifically, the material compositions of the present invention can be used to repair the ceramic-based top layer of the seal teeth horizontally in-module. In one embodiment, the method of the present invention may include depositing a repair coating of the material composition at room temperature, such as by spackling or slurry spraying, followed by curing with a localized heat treatment. In an embodiment where the localized curing is performed at the module level, the curing temperature is lower to protect the underlying substrate.

[0036] Therefore, in one embodiment, the material composition of the present invention is a slurry composition that can be applied to the damaged location of the alumina-based ceramic top layer of the damaged sealing tooth, so that the sealing tooth can be repaired by sintering at a lower temperature, such as about 300 degrees Celsius (°C) to about 900°C (°C), such as less than about 650°C. In certain embodiments, the slurry composition may include more than one sintering additive (e.g., low melting point glass) and a nucleating agent to convert the glass into a ceramic, thereby eliminating the brittleness of the coating. In addition, in one embodiment, a graded architecture (e.g., the relative amounts of alumina and sintering aids vary with the thickness of the ceramic top layer (from the middle layer to the upper surface)) is set to balance the requirements of adhesion and toughness. In addition, the present invention provides a unique non-line-of-sight coating coating method that does not lose density while also providing uniform density throughout the coating. In addition, the underlying layers and remaining components are protected from additional heat treatment by local low-temperature curing.

[0037] Thus, in one embodiment, the material composition of the present invention provides a technical effect of providing a chemical formulation that can be cured at a lower temperature by incorporating a sintering additive (e.g., a low melting point glass). In such an embodiment, the low melting point glass is treated to be converted into a crystalline phase during processing, thereby restoring the toughness of the ceramic top layer. In a specific embodiment, the material composition of the present invention is treated to provide an adhesive tensile strength greater than about four (4) megapascals (MPa) (about 600 pounds per square inch (PSI)). In addition, in one embodiment, the material composition of the present invention may have a density that matches (e.g., at least 70%) the rest of the ceramic top layer. In addition, in one embodiment, the material composition of the present invention may provide at least 70% of the corrosion resistance of the original component.

[0038] The material composition of the present invention also provides further benefits. For example, in one embodiment, the reduction in compressive stress of the bottom layer after shot peening (treatment) is minimal (or absent). In addition, the material composition of the present invention can repair damaged locations while also providing a smooth surface. In addition, localized heating can prevent the rest of the component from being subjected to heat treatment.

[0039] Referring now to the drawings, like reference numerals refer to like elements throughout. Figure 1-3 Various views of a gas turbine engine 10 (also referred to herein as engine 10 ) are shown, which may incorporate various aspects of the technology disclosed herein. Specifically, Figure 1 A partial schematic diagram of an embodiment of a gas turbine engine 10 that may incorporate various aspects of the disclosed technology is shown. Figure 2 Shows Figure 1 Detailed view of an embodiment of a compressor of a gas turbine engine of FIG. 1 , specifically illustrating an exemplary seal location 35 of the present invention. Figure 3 Shows Figure 2 1 is a simplified partial view of a compressor of a gas turbine engine of FIG. 1 , specifically showing one of the seal locations 35 of the present invention.

[0040] As shown, the gas turbine engine 10 has a longitudinal axis 11 and includes a fan 12, a low pressure compressor ("LPC") or "supercharger" 14, and a low pressure turbine ("LPT") 16, collectively referred to as the "low pressure system". The LPT 16 drives the fan 12 and the supercharger 14 through an inner shaft 18 (also referred to as the "LP shaft"). The engine 10 also includes a high pressure compressor ("HPC") 20, a combustor 22, and a high pressure turbine ("HPT") 24, collectively referred to as the "gas generator" or "core". The HPT 24 drives the HPC 20 through an outer shaft 26 (also referred to as the "HP shaft"). The high pressure system and the low pressure system can operate together in a known manner to produce a main flow or core flow and a fan flow or bypass flow. The inner shaft 18 and the outer shaft 26 are mounted in a plurality of rolling element bearings for rotation. The bearings are located in a closed portion of the engine 10 called the "oil sump".

[0041] Although the gas turbine engine 10 shown is a high bypass turbofan engine, the technology disclosed in this application can be equally applicable to turboprop engines, turbojets, and turboshaft engines, as well as turbine engines used in other vehicles or stationary applications. It should also be understood that turbine engines incorporating the technology of the present invention can be used in a variety of applications, including turbine engines in aircraft.

[0042] See Figure 2 and Figure 3 , the HPC 20 may include any number of rotor disks 30, 32 coupled to the HP shaft 26, two of which are labeled and generally referred to herein as the first rotor disk 30 and the second rotor disk 32 as shown. In addition, as shown, the rotor disks 30, 32 are axially spaced from each other by a predetermined distance. In addition, the rotor disks 30, 32 each support a plurality of compressor blades. The figure shows that the first compressor blade 40 and the second compressor blade 42 are supported respectively. The stator 34 or similar fixed structure may extend between the compressor blades 40, 42 and portions of the disks 30, 32.

[0043] See Figure 3, an example seal location 35 of the HPC 20 may include a seal ring 44 as described herein. The seal ring 44 may be attached to the first rotor disk 30 at its first end 46 and to the second rotor disk 32 at its second end 48. In addition, as shown, the seal ring 44 may include a seal body (e.g., a ring body portion) having any number of seal teeth 50 or similar types of seals extending therefrom. The seal teeth 50 may be arranged to face the stator 34. Any number of seal teeth 50 may be used. The seal teeth 50 may have any desired size or shape. When used, the seal ring 44 is sufficiently leak-proof by using the seal teeth 50. The seal ring 44 itself also transmits torque therethrough. In addition, the seal ring 44 may be used between any type of rotating components, such as between the stages of the LPC 14, HPT 24, and LPT 16.

[0044] See now Figure 4 , which is a detailed view of an embodiment of one of the sealing teeth 50 of the present invention. As shown in the figure, the sealing tooth 50 shown is composed of three layers. In a specific embodiment, as shown in the figure, the sealing tooth 50 includes a base layer 52, an intermediate layer 54 and a ceramic top layer 56. In one embodiment, the base layer 52 can be a nickel alloy or a titanium alloy. The intermediate layer 54 is typically a nickel-aluminide bonding coating. The ceramic top layer 56 is typically made of an aluminum oxide alloy. For certain sealing teeth, the intermediate layer and the ceramic top layers 54, 56 can be deposited on the base layer 52 using any suitable application method, such as by atmospheric plasma spraying (APS), additive manufacturing, etc.

[0045] See now Figure 5 6, respectively, illustrate a method 100 and a system 200 for repairing a multi-layer component of an engine (such as the seal tooth 50 described herein). More specifically, Figure 5 A flow chart showing an embodiment of a method 100 of repairing a multi-layer component of an engine according to the present invention is shown. Figure 6A-6B A schematic diagram of an embodiment of a system 200 for repairing a multi-layer component of an engine is shown. Additionally, the method 100 described herein may be used to repair the seal teeth 50 in-module (ie, without disassembling the gas turbine engine 10).

[0046] The method 100 described herein may generally be combined with Figures 1 to 4 1 and its components. However, it should be understood that the method 100 may be applied to any multi-layer component of an engine having any suitable configuration. Furthermore, it should be understood that the method 100 discussed herein is only used to describe aspects of the present invention and is not intended to be limiting. Furthermore, although Figure 5While method 100 having steps performed in a particular order is described for purposes of illustration and discussion, a person of ordinary skill in the art using the invention disclosed herein will appreciate that the steps of any method discussed herein may be changed, rearranged, expanded, omitted, or modified in various ways without departing from the scope of the present disclosure.

[0047] See Figure 5 As shown at (102), method 100 includes identifying a damaged location on a multi-layer component having at least one defect, the at least one defect extending at least partially into a ceramic top layer of the multi-layer component. Identifying the damaged location is accomplished, for example, manually or by an imaging device or sensor. As shown at (104), method 100 includes depositing a material composition onto the damaged location at a first temperature range to cover the damaged location, the material composition having more than one sintering additive. For example, in one embodiment, the first temperature range may include a temperature range of about 15°C to about 40°C, such as room temperature. As shown at (106), method 100 includes applying local curing to the material composition deposited at the damaged location at a second temperature range, the second temperature range being higher than the first temperature range. In a specific embodiment, the second temperature range may include a temperature ranging from about 300°C to about 900°C.

[0048] Combination Figures 6A-6E The embodiments of the system 200 and method 100 of the present invention can be better understood. Specifically, Fig. 6A As shown, a damaged location 202 having a defect is identified, the defect extending at least partially into the ceramic-based top layer 56, indicating regional damage (e.g., peeling). It should be understood that the defects described herein can be any defects, breaks, cracks, fractures, features, holes, depressions, grooves, features, etc. Figure 6B As shown, method 100 includes placing a protective layer 204, such as a film or a masking layer, around the damage location 202, thereby protecting the surrounding area of ​​the damage location 202. Figure 6C As shown, the method 100 includes depositing a material composition 206 on the damaged location 202 at a first temperature range, for example, using caulking or slurry spraying. For example, in one embodiment, as shown, the system 200 may include an application device 208 for depositing the material composition 206 at the damaged location 202. More specifically, in one embodiment, the application device 208 may be a caulking applicator, a slurry sprayer, or any other suitable application device.

[0049] In addition, the material composition 206 described herein includes at least one or more sintering additives and one or more nucleating agents. For example, in one embodiment, the sintering additive can be a low melting point glass, a thermosetting polymer that pyrolyzes into a ceramic, and / or a gel derived from an organometallic precursor. Therefore, the sintering additive is disposed to be converted into a crystalline phase during processing to restore the toughness of the ceramic top layer of the multi-layer component after repair, and the nucleating agent is disposed to convert the sintering additive into a crystalline phase to reduce brittleness. Therefore, the material composition 206 is particularly useful for horizontally repairing the ceramic top layer 56 of the sealing tooth 50 within a module. In one embodiment, the material composition 206 can be a slurry composition that can be applied to the damaged position 202 of the alumina-based ceramic top layer 56 of the damaged sealing tooth, so that the sealing tooth can be repaired by sintering at a lower temperature.

[0050] Herein, the low melting point glass may be a SiO2-based glass, or a non-silicon dioxide-based glass, such as a P2O5-based glass. In this case, the two families may be represented by M-SiO2 and N-P2O5. Therefore, in one embodiment, M includes SrO, ZnO, BaO, La2O3, Al2O3, B2O3, ZnO, Bi2O3, etc., or a combination thereof. In addition, in one embodiment, N includes CaO, Na2O, ZnO, Fe2O3, etc., or a combination thereof. In addition, examples of nucleating agents are V2O5, Cr2O3, Ba3(PO4)2, TiO2, and Fe2O3.

[0051] See also Fig.6D , the method 100 includes removing the protective layer 204 after depositing the material composition 206 at the damage location 202. In addition, as Fig. 6E As shown, the method 100 includes locally curing the material composition 206 deposited at the damage location at a second temperature range. For example, as shown, curing can be accomplished using any suitable heat source 210 (e.g., a heater, a heat exchanger, hot air, hot light, etc.). In addition, in some embodiments, after applying the local curing to the material composition 206 deposited at the damage location 202 at the second temperature range, the multi-layer component 206 has a uniform density across the multi-layer component (i.e., from one side of the damage location 202 to the other side).

[0052] The subject matter of the following clauses provides further aspects:

[0053] A method for in-module repair of an engine multilayer component, the method comprising: identifying a damaged location on the multilayer component having at least one defect, wherein the at least one defect extends at least partially into a ceramic top layer of the multilayer component; depositing a material composition onto the damaged location at a first temperature range to cover the damaged location, the material composition comprising more than one sintering additive; and applying local curing to the material composition deposited at the damaged location at a second temperature range, the second temperature range being higher than the first temperature range.

[0054] A method according to any of the preceding clauses, wherein the material composition further comprises a nucleating agent.

[0055] The method of any of the preceding clauses, further comprising disposing a protective layer around the damage location prior to depositing the material composition onto the damage location at the first temperature range.

[0056] The method of any of the preceding clauses, further comprising removing the protective layer from around the damage location after depositing the material composition onto the damage location.

[0057] A method according to any of the preceding clauses, wherein the one or more sintering additives comprise a low melting point glass.

[0058] A method according to any of the preceding clauses, wherein depositing the material composition to the damaged location at the first temperature range further comprises at least one of filling or slurry spraying.

[0059] Method according to any of the preceding clauses, wherein after applying local curing of the material composition deposited at the damage location in the second temperature range, the multilayer component has a uniform density throughout the component.

[0060] The method of any of the preceding clauses, wherein the first temperature range comprises a temperature range of about 15 degrees Celsius (°C) to about 30°C.

[0061] The method of any of the preceding clauses, wherein the second temperature range comprises temperatures equal to or less than about 650 degrees Celsius (°C).

[0062] A method according to any of the preceding clauses, wherein the ceramic-based top layer is composed of an alumina-based alloy.

[0063] A method according to any of the preceding clauses, wherein the multi-layer component of the engine comprises one or more seal teeth of a seal of the engine.

[0064] A system for in-module repair of a ceramic top layer of a multi-layer engine component, the system comprising: a material composition for covering defects in the ceramic top layer, the material composition comprising a sintering additive and a nucleating agent; and a heat source, the heat source being used to apply local heat to the material composition at a damaged location to solidify the material composition, wherein the sintering additive is converted into a crystalline phase during the treatment process to restore the toughness of the ceramic top layer of the multi-layer component after repair, and the nucleating agent converts the sintering additive into a ceramic material to reduce the brittleness of the repaired multi-layer component.

[0065] A system according to any of the preceding clauses, further comprising a protective layer for protecting an area surrounding the damage location.

[0066] The system of any of the preceding clauses, wherein the sintering additive comprises a low melting point glass.

[0067] The system of any of the preceding clauses, further comprising an application device for depositing the material composition onto the damage location at a first temperature range.

[0068] A system according to any of the preceding clauses, wherein the application device comprises at least one of a fill applicator or a slurry sprayer.

[0069] A system according to any of the preceding clauses, wherein the first temperature range includes a temperature range of about 15 degrees Celsius (°C) to about 30°C, and the heat source applies local heat to the material composition at a second temperature range, and the second temperature range includes a temperature equal to or less than about 650 degrees Celsius (°C).

[0070] A system according to any of the preceding clauses, wherein, after repair and curing, the multilayer component has a uniform density throughout the material composition.

[0071] The system of any of the preceding clauses, wherein the ceramic-based top layer is comprised of an alumina-based alloy.

[0072] A system according to any of the preceding clauses, wherein the multi-layer component of the engine comprises one or more seal teeth of a seal of the engine.

[0073] This specification uses examples to disclose the present technology (including its best mode) and is also intended to enable those skilled in the art to practice the present technology, including making and using devices or systems and performing introduced methods. The patent scope of the present technology is defined by the claims and may include other examples that occur to those skilled in the art. If such other examples include structural elements that are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims, it is meant that such other examples fall within the scope of the claims.

Claims

1. A method for in-module repair of a multi-layer engine component, the method comprising: identifying a damage location on a multi-layer component having at least one defect extending at least partially into a ceramic-based top layer of the multi-layer component; depositing a material composition onto the damaged location at a first temperature range to cover the damaged location, the material composition comprising one or more sintering additives; Local curing is applied to the material composition deposited at the damaged location at a second temperature range, the second temperature range being higher than the first temperature range.

2. The method according to claim 1, wherein: The material composition further comprises a nucleating agent.

3. The method according to claim 1, wherein: The method also includes disposing a protective layer around the damage site prior to depositing the material composition onto the damage site at the first temperature range.

4. The method according to claim 3, wherein: The method further includes removing the protective layer from around the damaged location after depositing the material composition onto the damaged location.

5. The method according to claim 1, wherein: The one or more sintering additives include a low melting point glass.

6. The method according to claim 1, wherein: Depositing the material composition to the damaged location at the first temperature range further includes at least one of filling or slurry spraying.

7. The method according to claim 1, wherein: After applying localized curing of the material composition deposited at the damaged location in the second temperature range, the multi-layer component has a uniform density throughout the multi-layer component.

8. The method according to claim 1, wherein: The first temperature range includes a temperature range of about 15 degrees Celsius (°C) to about 30°C.

9. The method according to claim 1, wherein: The second temperature range includes temperatures equal to or less than about 650 degrees Celsius (° C.).

10. A system for in-module repair of a ceramic top layer of a multi-layer engine component, the system comprising: A material composition for covering defects at a damaged location of a ceramic-based top layer, the material composition comprising a sintering additive and a nucleating agent; and a heat source for applying localized heat to the material composition at the damaged location to cure the material composition, The sintering additive is converted into a crystalline phase during the treatment process to restore the toughness of the ceramic-based top layer of the multilayer component after the repair, The nucleating agent converts the sintering additive into a ceramic material to reduce the brittleness of the repaired multi-layer component.

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