Double-layer composite sealing structure for turbine blade of aero-engine
By using a dual-layer composite structure of metal functional layer and ceramic fiber functional layer of aero-engine turbine blades, the problem of insufficient heat insulation and sealing performance of sealing structure under high temperature is solved, achieving stable sealing and dynamic gap adaptation in high temperature environment, and improving the service life and sealing ability of sealing sheet.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIHANG UNIV
- Filing Date
- 2026-03-31
- Publication Date
- 2026-05-12
AI Technical Summary
Existing sealing structures for aero-engine turbine blades cannot simultaneously provide good thermal insulation and sealing performance at high temperatures, and they cannot adapt to dynamic gap changes caused by the difference in thermal expansion coefficients between the CMC blades and the metal disc, resulting in poor sealing performance.
The structure employs a dual-layer composite structure consisting of a metal functional layer and a ceramic fiber functional layer. The metal functional layer provides structural stiffness and elastic recovery force, while the ceramic fiber functional layer contacts high-temperature combustion gas and provides thermal insulation. Through functional gradient design and mechanical locking, it achieves active adaptation to dynamic gaps and sealing compensation.
It improves the production consistency and maintenance convenience of the sealing structure, extends the service life of the metal functional layer, enhances the sealing performance and anti-delamination ability in high-temperature environments, and ensures stability and sealing effect under extreme conditions.
Smart Images
Figure CN122014360A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of sealing hot-end components of aero-engines, and in particular to a double-layer composite sealing structure for aero-engine turbine blades. Background Technology
[0002] As aero engines and gas turbines develop towards higher thrust-to-weight ratios and higher thermal efficiency, turbine inlet temperatures are constantly increasing. This places extreme demands on the temperature resistance of turbine hot-end components, leading to the gradual application of ceramic matrix composites in turbine blades due to their superior high-temperature performance.
[0003] However, the difference in thermal expansion coefficients between the CMC blades and the metal disk causes drastic and nonlinear dynamic changes in the gap between the blade tenon and the disk tenon during operation. This presents an unprecedented challenge to the sealing structure at this connection: it must be able to continuously adapt to a wide range of dynamic gaps under extreme temperatures, effectively preventing high-temperature combustion gases from intruding into the disk cavity. Furthermore, during the assembly of aero-engine turbine blades, a certain amount of gaps inevitably forms between adjacent blade sills. High-temperature combustion gases in the blade cascade passages may mix with the cooling airflow in the engine air system through these gaps, causing ablation of the blades and sills.
[0004] Therefore, it is necessary to install a sealing structure at the blade edge to prevent the intrusion of high-temperature combustion gases. Currently, there are two main types of sealing solutions: one is an elastic seal made of high-temperature alloy, which has a certain strength and wear resistance, but insufficient thermal insulation performance, which easily leads to heat conduction to the blade substrate and surrounding components, and is prone to oxidation, creep and elastic failure at increasingly higher temperatures; the other is a ceramic-based seal, which is resistant to high temperatures, but lacks active elastic recovery force, cannot reliably track dynamic gap changes, has poor structural toughness and weak vibration resistance, is prone to falling off and cracking under high-frequency vibration, cannot withstand long-term blade deformation impact, and has limited sealing performance. Summary of the Invention
[0005] To address the issue of the inability to simultaneously achieve both thermal insulation and sealing performance in turbine blade sealing structures, this application provides a double-layer composite sealing structure for aero-engine turbine blades.
[0006] The technical solution provided in this application for a double-layer composite sealing structure for aero-engine turbine blades is as follows: A double-layer composite sealing structure for aero-engine turbine blades includes a sealing sheet. Mounting grooves are respectively formed on the inner sides of two adjacent turbine blade rim plates. The two ends of the sealing sheet are respectively inserted into the two adjacent mounting grooves. The sealing sheet includes a metal functional layer and a ceramic fiber functional layer. The ceramic fiber functional layer is located on the side of the metal functional layer closer to the gas flow G.
[0007] By adopting the above technical solution, the dual-layer structure of the metal functional layer and the ceramic fiber functional layer is integrated into an integrated structure, simplifying the assembly process, improving production consistency and maintenance convenience. The dual-layer structure also provides failure redundancy; even if the ceramic fiber functional layer is partially worn, the metal functional layer can still maintain basic sealing function, ensuring high safety. Through the functional gradient design of the metal functional layer and the ceramic fiber functional layer, the ceramic fiber functional layer, in contact with high-temperature combustion gas, can effectively resist combustion gas erosion and surface wear, allowing the sealing sheet to maintain a lower operating temperature of its core elastic component, the metal functional layer, while in contact with high-temperature combustion gas, thus extending the service life of the metal functional layer. The elasticity of the metal functional layer gives the sealing sheet excellent flexibility and deformation capacity, which can accurately compensate for the complex dynamic gap changes caused by the different thermal expansion ratios of the CMC blades and the metal turbine disk, ensuring sufficient sealing at the sealing interface. This comprehensively breaks through the performance limits of a single material, enabling the sealing sheet to maintain excellent elastic sealing capability even in ultra-high temperature environments.
[0008] Preferably, the middle portion of the sealing sheet arches toward the side closer to the gas flow G.
[0009] By adopting the above technical solution, when the engine is working, the ceramic fiber functional layer directly contacts the high-temperature combustion gas and provides heat insulation, while the metal functional layer undergoes elastic deformation under the set preload, actively adapting to the gap change and maintaining a seal.
[0010] Preferably, the material selected for the metal functional layer is Haynes 214 high-temperature alloy foil.
[0011] By adopting the above technical solution, Haynes 214 high-temperature alloy foil provides the main structural stiffness and elastic recovery force, ensuring the control of the sealing interface gap.
[0012] Preferably, the ceramic fiber functional layer is made of Nextel™ 440 fiber woven fabric.
[0013] By adopting the above technical solution, Nextel™ 440 fiber woven fabric directly withstands high temperatures, blocks heat transfer to the metal layer, and uses its flexibility to compensate for microscopic surface unevenness.
[0014] Preferably, a high-temperature resistant inorganic adhesive layer is installed between the metal functional layer and the ceramic fiber functional layer, and the metal functional layer and the ceramic fiber functional layer are bonded together by the high-temperature resistant inorganic adhesive layer.
[0015] By adopting the above technical solution, a high-temperature resistant inorganic adhesive layer is installed between the metal functional layer and the ceramic fiber functional layer, which can effectively enhance the bonding strength between the two, improve the stability and high-temperature resistance of the overall structure, and ensure stable sealing performance under extreme conditions.
[0016] Preferably, the sealing sheet is a thin plate, the metal functional layer includes a middle section and two bent sections, the side of the ceramic fiber functional layer away from the gas flow G is in contact with the middle section, the bent sections include a connecting section one connected to the middle section and a connecting section two connected to the connecting section one, the two ends of the ceramic fiber functional layer are in contact with the connecting section one, and the side of the ceramic fiber functional layer near the gas flow G is in contact with the connecting section two.
[0017] By adopting the above technical solution, the bending section covers and presses the edge of the ceramic fiber functional layer to form a mechanical lock, which makes the sealing sheet more adaptable under dynamic conditions, can accurately compensate for gap changes caused by thermal expansion, and further optimize the sealing performance.
[0018] Preferably, the metal functional layer is made of PM2000 ODS alloy foil, and the ceramic fiber functional layer is made of Nextel™ 312 fiber needled felt.
[0019] By adopting the above technical solution, PM2000 ODS alloy foil is selected as the metal functional layer material and Nextel™ 312 fiber needled felt is selected as the ceramic fiber functional layer material. The combination of the two provides higher thermal stability and mechanical strength, and improves the reliability of the overall sealing structure in high-temperature environments.
[0020] Preferably, the sealing sheet is a continuous corrugated shape, and the metal functional layer and the ceramic fiber functional layer are locally connected at each crest and trough by micro-laser spot welding.
[0021] By adopting the above technical solution and using a continuous corrugated sealing sheet structure, the metal functional layer and the ceramic fiber functional layer are locally connected at the crests and troughs through micro-laser spot welding, which enhances the anti-delamination ability under high-speed airflow scouring and ensures the stability and sealing performance of the sealing structure under extreme working conditions.
[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. The dual-layer structure of the metal functional layer and the ceramic fiber functional layer is combined into an integrated structure, which simplifies the assembly process, improves production consistency and maintenance convenience, and the dual-layer structure also provides failure redundancy. Even if the ceramic fiber functional layer is partially worn, the metal functional layer can still maintain basic sealing function, which ensures high safety. 2. Through the functional gradient design of the metal functional layer and the ceramic fiber functional layer, the ceramic fiber functional layer comes into contact with high-temperature gas, which can effectively resist gas erosion and surface wear. This allows the sealing sheet to reduce the working temperature of its core elastic component, the metal functional layer, while it is in contact with high-temperature gas, thus extending the service life of the metal functional layer. 3. The elasticity of the metal functional layer gives the sealing sheet excellent flexibility and deformation ability, which can accurately compensate for the complex dynamic gap changes caused by the different thermal expansion ratios of the CMC blades and the metal turbine disk, ensuring sufficient sealing at the sealing interface. This comprehensively breaks through the performance limits of a single material, enabling the sealing sheet to maintain excellent elastic sealing ability even in ultra-high temperature environments. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the installation structure of the sealing plate in Embodiment 1 of this application.
[0024] Figure 2 This is a schematic diagram of the overall structure of the sealing sheet in Embodiment 1 of this application.
[0025] Figure 3 This is a schematic diagram of the overall structure of the sealing sheet in Embodiment 2 of this application.
[0026] Figure 4 This is a schematic diagram of the overall structure of the sealing sheet in Embodiment 3 of this application.
[0027] Reference numerals: 1. Sealing sheet; 2. Metal functional layer; 21. Middle section; 22. Bending section; 221. Connecting section one; 222. Connecting section two; 3. Ceramic fiber functional layer; 4. High-temperature resistant inorganic adhesive layer. Detailed Implementation
[0028] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.
[0029] This application discloses a double-layer composite sealing structure for aero-engine turbine blades. Example
[0030] Reference Figure 1 and Figure 2 The double-layer composite sealing structure of the turbine blade of the aero-engine includes a sealing plate 1. The inner sides of the blades of two adjacent turbine blades are respectively provided with mounting grooves. The two ends of the sealing plate 1 are respectively inserted into the two adjacent mounting grooves. The middle part of the sealing plate 1 arches towards the side closer to the gas flow G.
[0031] Reference Figure 2 The sealing sheet 1 includes a metal functional layer 2 and a ceramic fiber functional layer 3, with the ceramic fiber functional layer 3 located on the side of the metal functional layer 2 closer to the gas flow G. A high-temperature resistant inorganic adhesive layer 4 is installed between the metal functional layer 2 and the ceramic fiber functional layer 3, and the metal functional layer 2 and the ceramic fiber functional layer 3 are bonded together by the high-temperature resistant inorganic adhesive layer 4.
[0032] Reference Figure 2The metal functional layer 2 is made of 0.1mm thick Haynes 214 high-temperature alloy foil, providing the main structural stiffness and elastic recovery force to ensure control of the sealing interface gap. The ceramic fiber functional layer 3 is made of 0.5mm thick Nextel™ 440 fiber woven fabric, directly bearing the high temperature, blocking heat transfer to the metal layer, and using its flexibility to compensate for microscopic surface unevenness. When the sealing plate 1 is installed in the mounting groove, the outer surface of the ceramic fiber functional layer 3 is tightly fitted to the inner wall of the mounting groove near the gas flow G. When the engine is running, the ceramic fiber functional layer 3 directly contacts the high-temperature gas and provides heat insulation, while the metal functional layer 2 undergoes elastic deformation under the set preload, actively adapting to gap changes and maintaining a seal.
[0033] The implementation principle of Embodiment 1 of this application is as follows: The dual-layer structure of the metal functional layer 2 and the ceramic fiber functional layer 3 is combined into an integrated structure, which simplifies the assembly process, improves production consistency and maintenance convenience, and the dual-layer structure also provides failure redundancy. Even if the ceramic fiber functional layer 3 is partially worn, the metal functional layer 2 can still maintain basic sealing function, which is highly safe. Through the functional gradient design of the metal functional layer 2 and the ceramic fiber functional layer 3, the ceramic fiber functional layer 3 comes into contact with high-temperature gas and can effectively resist gas erosion and surface wear. This allows the sealing sheet 1 to contact high-temperature gas while the working temperature of its core elastic component, the metal functional layer 2, is reduced, thus extending the service life of the metal functional layer 2. The elasticity of the metal functional layer 2 gives the sealing sheet 1 excellent flexibility and deformation ability, which can accurately compensate for the complex dynamic gap changes caused by the different thermal expansion ratios of the CMC blades and the metal turbine disk, ensuring sufficient sealing at the sealing interface. This comprehensively breaks through the performance limits of a single material, allowing the sealing sheet 1 to maintain excellent elastic sealing ability even in ultra-high temperature environments. Example
[0034] Reference Figure 3 The difference between this embodiment and Embodiment 1 is that the sealing sheet 1 is a thin plate, the metal functional layer 2 includes a middle section 21 and two bent sections 22, and the side of the ceramic fiber functional layer 3 away from the gas flow G is attached to the middle section 21. The bent sections 22 cover and press the edges of the ceramic fiber functional layer 3 to form a mechanical lock. The bent sections 22 include a first connecting section 221 connected to the middle section 21 and a second connecting section 222 connected to the first connecting section 221. The two ends of the ceramic fiber functional layer 3 are attached to the first connecting section 221, and the side of the ceramic fiber functional layer 3 near the gas flow G is attached to the second connecting section 222.
[0035] Reference Figure 3 The metal functional layer 2 is made of PM2000 ODS alloy foil with a thickness of 0.08mm, and the ceramic fiber functional layer 3 is Nextel™ 312 fiber needled felt.
[0036] The implementation principle of Embodiment 2 of this application is as follows: the bent section 22 covers and presses the edge of the ceramic fiber functional layer 3 to form a mechanical lock, so that the sealing sheet 1 has better adaptability under dynamic conditions, can accurately compensate for the gap change caused by thermal expansion, and further optimize the sealing performance. Example
[0037] Reference Figure 4 The difference between this embodiment and embodiment 1 is that the sealing sheet 1 is a continuous corrugated shape, and the metal functional layer 2 and the ceramic fiber functional layer 3 are locally connected at each peak and trough by micro laser spot welding, which enhances the anti-delamination ability under high-speed airflow.
[0038] The implementation principle of Embodiment 3 of this application is as follows: a continuous corrugated sealing sheet 1 structure is adopted, so that the metal functional layer 2 and the ceramic fiber functional layer 3 are locally connected at the crest and trough by micro laser spot welding, which enhances the anti-delamination ability under high-speed airflow scouring and ensures the stability and sealing of the sealing structure under extreme working conditions.
[0039] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.
Claims
1. A double-layer composite sealing structure for aero-engine turbine blades, characterized in that: The sealing plate (1) includes a mounting groove on the inner side of the blades of two adjacent turbine blades. The two ends of the sealing plate (1) are inserted into the two adjacent mounting grooves. The sealing plate (1) includes a metal functional layer (2) and a ceramic fiber functional layer (3). The ceramic fiber functional layer (3) is located on the side of the metal functional layer (2) near the gas flow G.
2. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The middle portion of the sealing plate (1) arches toward the side closer to the gas flow G.
3. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The material selected for the metal functional layer (2) is Haynes 214 high-temperature alloy foil.
4. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The ceramic fiber functional layer (3) is made of Nextel™ 440 fiber woven fabric.
5. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: A high-temperature resistant inorganic adhesive layer (4) is installed between the metal functional layer (2) and the ceramic fiber functional layer (3), and the metal functional layer (2) and the ceramic fiber functional layer are bonded together by the high-temperature resistant inorganic adhesive layer (4).
6. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The sealing sheet (1) is a thin plate. The metal functional layer (2) includes a middle section (21) and two bent sections (22). The side of the ceramic fiber functional layer (3) away from the gas flow G is attached to the middle section (21). The bent section (22) includes a connecting section one (221) connected to the middle section (21) and a connecting section two (222) connected to the connecting section one (221). The two ends of the ceramic fiber functional layer (3) are attached to the connecting section one (221). The side of the ceramic fiber functional layer (3) near the gas flow G is attached to the connecting section two (222).
7. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The metal functional layer (2) is made of PM2000 ODS alloy foil, and the ceramic fiber functional layer (3) is made of Nextel™ 312 fiber needled felt.
8. The double-layer composite sealing structure for aero-engine turbine blades according to claim 1, characterized in that: The sealing sheet (1) is a continuous corrugated shape, and the metal functional layer (2) and the ceramic fiber functional layer (3) are locally connected at each peak and trough by micro laser spot welding.