Directionally isostatic composite honeycomb structure and method of making same

Abstract

The present application relates to a kind of directional even heat composite honeycomb structure and its manufacturing method, belong to honeycomb structure technical field, solve the problem of local heating caused by the insufficient heat dissipation performance of existing honeycomb structure in actual application process.The present application provides a kind of directional even heat composite honeycomb structure, including directional even heat layer, upper skin, honeycomb core and core filler, lower skin from top to bottom in turn.In existing lightweight honeycomb structure, the heat capacity of honeycomb structure is improved using core filler, and the heat dissipation speed is increased using directional even heat layer.The design of this double thermal protection measures is used to solve the problem of local heating caused by the insufficient heat dissipation performance of traditional honeycomb structure in actual application process, thereby effectively improving the stability and reliability of honeycomb structure in high temperature environment application.

Description

Technical Field

[0001] This invention relates to the field of honeycomb structure technology, and in particular to a directional homogenized composite honeycomb structure and its manufacturing method. Background Technology

[0002] With the development of aviation and aerospace, there is a need to develop new structures with superior overall performance. At this time, honeycomb structures, with their excellent mechanical properties, lightweight, thermal insulation, and sound insulation, have attracted the attention of scholars. Due to their high cost, honeycomb structures were initially only used in the aerospace field. However, with continuous technological advancements and the development of the national economy, honeycomb structures have gradually begun to be used in civilian applications. In the last decade or so, honeycomb structures have been applied in transportation, construction, energy, packaging, and other fields. In these fields, honeycomb structures are used as a structural and lightweight material, reducing the overall weight of devices while providing good mechanical properties. Due to the needs of engineering applications, higher and more demanding requirements have been placed on the performance of honeycomb structures, such as higher mechanical properties and thermal insulation performance.

[0003] Currently, most honeycomb structures used employ a single honeycomb structure (upper and lower skins and a middle honeycomb core) to achieve overall structural lightweighting, which can meet the lightweighting and environmental temperature requirements under certain working conditions. This single honeycomb structure has certain heat resistance, but under certain high-temperature environments, especially when subjected to concentrated heat, it can lead to localized high-temperature accumulation, posing a potential risk of insufficient high-temperature performance. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a directional heat-equalizing composite honeycomb structure and its manufacturing method. This addresses the problem of severe localized overheating caused by insufficient heat dissipation performance in traditional honeycomb structures during practical applications.

[0005] The objective of this invention is mainly achieved through the following technical solutions:

[0006] On the one hand, the present invention designs a directional heat-equalizing composite honeycomb structure, including a directional heat-equalizing layer, an upper skin, a honeycomb core and core filler, and a lower skin arranged sequentially from top to bottom.

[0007] Furthermore, the directional heat dissipation layer is made of a two-dimensional material base, including but not limited to ceramic materials, high thermal conductivity graphene films, graphene-based composite materials, and graphene-based ceramic composite materials, with a thickness of 0.01–10 mm.

[0008] Furthermore, the upper skin is made of either a titanium-based or nickel-based alloy, with a thickness ranging from 0.1 mm to 20 mm.

[0009] Furthermore, the lower skin is made of either a titanium-based or nickel-based alloy, with a thickness ranging from 0.1 mm to 20 mm.

[0010] Furthermore, the honeycomb core has a honeycomb-like grid structure with a thickness of 0.01–3 mm and a height of 1–50 mm, and is made of titanium alloy.

[0011] Furthermore, the core filler has a density of less than 1 g / cm³. 3 One of silicon-based fibers, silicon-based aerogels, or graphene aerogels.

[0012] On the other hand, the present invention also provides a method for manufacturing a directional heat-equalizing composite honeycomb structure, which includes the following steps:

[0013] S1. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the lower skin.

[0014] S2. Using vacuum brazing or gas-shielded brazing, the honeycomb core is first welded to the lower skin.

[0015] S3. Fill the honeycomb core with the honeycomb core material mechanically and / or manually;

[0016] S4. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the upper skin.

[0017] S5. Weld the upper skin and the honeycomb core together to obtain a honeycomb structure;

[0018] S6. A two-dimensional material-based oriented heat dissipation layer is prepared on the outer surface of the skin of the honeycomb structure by spraying, brazing or bonding.

[0019] S7. After the final welding of the components is completed, the whole structure undergoes stabilization heat treatment.

[0020] Furthermore, in step S1 or S4, the thickness of the solder layer is 0.01 to 3.5 mm.

[0021] Furthermore, in step S5, the welding temperature is 450–1400℃, and the holding time is 20–60 min.

[0022] Furthermore, in step S6, the spraying methods include flame spraying, plasma spraying, and cold spraying. When using the spraying method, the directional heat-dissipating material is sprayed onto the upper skin at a temperature of 800–1200℃ (excluding cold spraying). A curing treatment is also required, with a curing temperature of 25–450℃ and a curing time of 0–180 minutes. When using the welding method, the brazing temperature is 800–960℃, and the holding time is 10–45 minutes, using Ti-Cu-Ag type brazing filler metal. When using the bonding method, a high-temperature resistant inorganic adhesive is used. The adhesive is evenly applied to the bonding surface, first placed at room temperature for 2–12 hours, then maintained at 60–100℃ for 1–4 hours, and subsequently maintained at 100–300℃ for 2 hours to complete the bonding.

[0023] Furthermore, in step S7, the stabilization heat treatment temperature is 20–100°C lower than the welding temperature.

[0024] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0025] a) Directional heat dissipation function and high thermal stability: Based on a single honeycomb structure, this invention adds a directional heat equalization layer to the surface. This structure can conduct heat laterally to low-temperature areas, greatly avoiding the accumulation of heat on the surface, reducing the effective heat input per unit area in the heat concentration area of ​​the honeycomb surface, making the surface energy distribution more uniform, and hindering some heat from being conducted into the honeycomb interior. This effectively solves the problem of severe local heating caused by insufficient heat resistance of honeycomb structures in practical applications, thereby effectively improving the thermal stability of the honeycomb structure.

[0026] b) High heat capacity and good heat resistance: Based on the single honeycomb structure, this invention adds a core filler inside the honeycomb core, which can effectively hinder the conduction and radiation of heat inside the honeycomb, improve the heat capacity of the honeycomb structure, thereby reducing the effective amount of heat transferred from the hot end to the cold end of the honeycomb, which can effectively achieve secondary control of the introduced heat, avoid overheating failure due to excessive heat introduction, and improve the heat resistance of the overall structure.

[0027] c) High interlayer bonding strength and high mechanical properties: This invention improves the reliability of the connection through the optimized combination of brazing materials and brazing processes, satisfying and realizing the welding between skins and honeycomb cores made of different titanium alloys. Surface treatment was performed before welding the honeycomb core to the skin, and before welding the honeycomb skin to the directional heat spreader layer, followed by vacuum diffusion welding, vacuum brazing, or brazing under a protective atmosphere. After the final welding of the components, a stabilization heat treatment was performed on the entire structure, further improving the interlayer bonding strength and thus effectively enhancing the mechanical properties of the honeycomb structure.

[0028] d) The directional heat spreader of the present invention can be made of highly oriented and dense ceramic material. The highly oriented and dense ceramic material can be any two or more raw materials selected from small-particle-size highly oriented ceramic powder, large-particle-size highly oriented ceramic powder and graphene oxide aqueous solution. For example, a mixture of small-particle-size highly oriented ceramic powder and large-particle-size highly oriented ceramic powder, or a mixture of small-particle-size highly oriented ceramic powder and graphene oxide aqueous solution, or a mixture of large-particle-size highly oriented ceramic powder, small-particle-size highly oriented ceramic powder and graphene oxide aqueous solution; and finally, a binder is added to improve the orientation and density during the green body structure forming process, so as to improve the high orientation and excellent performance of the final obtained ceramic material.

[0029] This invention utilizes a blend of small-particle-size highly oriented ceramic powder and large-particle-size highly oriented ceramic powder, and controls the ratio between the two. By selecting highly oriented ceramic powders with different orientation morphologies (such as fibrous, columnar, and flake-like) and different particle sizes, it is possible to obtain highly oriented and dense ceramics with high density and mechanical strength.

[0030] This invention utilizes small-particle-size highly oriented ceramic powder or large-particle-size highly oriented ceramic powder mixed with an aqueous solution of graphene oxide to optimize the orientation and performance of the ceramic.

[0031] This invention employs a mixture of small-particle-size highly oriented ceramic powder and large-particle-size highly oriented ceramic powder with an aqueous solution of graphene oxide, and with the assistance of a binder, to strictly control the particle size and weight ratio of the highly oriented ceramic powder. By filling the gaps between the large-particle-size highly oriented ceramic powder with small-particle-size powder, the density of the ceramic is improved. The orientation preference of the large-particle-size highly oriented ceramic powder during the stacking process is utilized to optimize the orientation of the ceramic, and the large-particle-size highly oriented ceramic powder acts as a "structural bridge" between the small-particle-size highly oriented ceramic powder and the binder, greatly enhancing the mechanical strength of the ceramic.

[0032] The present invention provides a method for preparing highly oriented and dense ceramics. By designing a powder mixing method, introducing graphene oxide, and employing vacuum filtration, the orientation of the mixed powder during the drying process is further optimized. The highly oriented ceramics prepared by this method have lower porosity than ceramics prepared by traditional methods, and exhibit excellent material properties even under pressureless sintering conditions, such as ultra-high in-plane thermal conductivity and ultra-high flexural strength.

[0033] Other features and advantages of the invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained from what is particularly pointed out in the description and the drawings. Attached Figure Description

[0034] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0035] Figure 1 This is a schematic diagram of the directional homogenized heat-dissipating composite honeycomb structure in an embodiment of the present invention;

[0036] Figure 2 The back temperature test diagrams for the ceramic prepared in Example 6 and Comparative Example 1 are shown in Example 3 of the present invention.

[0037] Figure 3 The scanning electron microscope image of the ceramic fracture surface obtained in Example 3 of this invention;

[0038] Figure 4 The scanning electron microscope image of the ceramic fracture surface obtained in Example 2 of this invention;

[0039] Figure 5 The scanning electron microscope image of the ceramic fracture surface obtained in Example 1 of this invention;

[0040] Figure 6 The scanning electron microscope image of the ceramic fracture surface obtained in Example 4 of this invention;

[0041] Figure 7 The scanning electron microscope image of the ceramic fracture surface obtained in Example 7 of this invention;

[0042] Figure 8 The scanning electron microscope image of the ceramic fracture surface obtained in Example 8 of this invention is shown.

[0043] Figure label:

[0044] 11-Upper skin; 12-Lower skin; 2-Honeycomb core; 3-Oriented heat dissipation layer; 4-Core filler. Detailed Implementation

[0045] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0046] On the one hand, this invention designs a directional heat-equalizing composite honeycomb structure, such as Figure 1 As shown, it includes: an upper skin 11, a lower skin 12, a honeycomb core 2, a directional heat dissipation layer 3, and a core filler 4.

[0047] Specifically, the directional heat dissipation layer is made of two-dimensional material-based materials, including but not limited to ceramic materials, high thermal conductivity graphene films, graphene-based composite materials, and graphene-based ceramic composite materials, with a thickness of 0.01 to 10 mm.

[0048] It should be noted that the directional heat dissipation layer, located on the outermost layer, can largely prevent heat accumulation on the surface, conducting heat laterally to lower-temperature areas and reducing the effective heat input per unit area in areas of concentrated heat on the honeycomb surface. Concentrated heat distribution often leads to localized heating of the structure, compromising its performance. This directional heat dissipation layer conducts heat to the surrounding lower-temperature areas, resulting in a wider heat distribution area on the structure and increasing heat dissipation, effectively preventing heat accumulation.

[0049] Specifically, the upper skin is made of either a titanium-based or nickel-based alloy, with a thickness ranging from 0.1 mm to 20 mm.

[0050] Specifically, the lower skin is made of either a titanium-based or nickel-based alloy, with a thickness ranging from 0.1 mm to 20 mm.

[0051] In one possible implementation, TA15 titanium alloy is used as the upper and lower skins of the directional homogenizing composite honeycomb structure. TA15 titanium alloy is a near-α type titanium alloy with high Al equivalent. Its main strengthening mechanism is solid solution strengthening by adding the α-stabilizing element Al, supplemented by the addition of the neutral element Zr and the β-stabilizing elements Mo and V for further strengthening and improved processing properties. Therefore, this alloy possesses both the good hot strength and weldability of α type titanium alloys and the processing plasticity of (α+β) type titanium alloys, making it particularly suitable for manufacturing various welded parts.

[0052] Specifically, the honeycomb core has a honeycomb-like grid structure with a thickness of 0.01–3 mm and a height of 1–50 mm, and is made of titanium alloy.

[0053] It should be noted that aerospace equipment generates a large amount of heat through friction with the air during high-speed flight. The impact of this large amount of highly concentrated heat is a problem that modern and future high-precision manufacturing industries must consider. Titanium alloys are widely used in the aerospace field due to their excellent high-temperature performance and high specific strength; therefore, titanium alloys can be selected for the upper and lower skins and honeycomb cores.

[0054] Specifically, the core filler has a density of less than 1 g / cm³. 3 One of silicon-based fibers, silicon-based aerogels, or graphene aerogels.

[0055] In one possible implementation, the silicon-based fiber is silica fiber, which is used as the core filler. The density is controlled by adjusting the mass-to-volume ratio of the silica fiber. The silica fiber has a length of 10.00–11.00 mm and a diameter of 1–100 μm. Silica fiber has a low thermal conductivity and high thermal resistance, and is non-polluting and chemically stable. As a core filler in a honeycomb structure, it can increase the overall heat capacity of the structure, effectively prevent the conduction and convection effects of internal airflow, and thus increase the structure's heat capacity and effectively reduce internal heat transfer.

[0056] In one possible implementation, the silica-based aerogel is a silica aerogel with a specific surface area of ​​300-1500 m². 2 / g, with an average pore size of 6-10nm and a porosity of 80% of the total structure, reducing radiative heat transfer between the inner surfaces of the honeycomb and convective heat transfer of the air inside the core.

[0057] In one possible implementation, the core filler is graphene aerogel with a density of less than 1 g / cm³. 3 Specific surface area reaches 2630m² 2 / g exhibits excellent thermal insulation properties in vacuum structure components. Its abundant internal cavities reduce heat conduction, thereby improving the structure's thermal insulation performance.

[0058] It should be noted that the core filling material inside the honeycomb can effectively hinder the conduction and radiation of heat inside the honeycomb, thereby increasing the heat capacity of the honeycomb structure and reducing the effective amount of heat transferred from the hot end to the cold end. This can effectively achieve secondary control of the introduced heat and prevent the protected device from overheating and failing due to excessive heat introduction.

[0059] The directional heat dissipation layer is made of a two-dimensional material matrix, including but not limited to ceramic materials, high thermal conductivity graphene films, graphene-based composite materials, and graphene-based ceramic composite materials, with a thickness of 0.01–10 mm. The directional heat dissipation layer can be formed on the outer surface of the skin of the honeycomb structure by spraying, brazing, or bonding.

[0060] Furthermore, the high thermal conductivity graphene film is a graphene high thermal conductivity film with a thickness of 100-400 μm. The film is made of graphene as raw material and is formed by stacking multiple layers of graphene. The thermal conductivity is >1000 W / m·K.

[0061] Furthermore, the ceramic material is a highly oriented and dense ceramic material, and the raw materials for preparation include any two or more of the following: small-particle-size highly oriented ceramic powder, large-particle-size highly oriented ceramic powder, and graphene oxide aqueous solution, as well as a binder; wherein the small-particle-size highly oriented ceramic powder and the large-particle-size highly oriented ceramic powder are selected from α-Al2O3, hBN, SiC, layered molybdate, Si3N4, and SiO2; and the binder is selected from yttrium oxide, magnesium oxide, aluminum oxide, silicon dioxide, and mullite.

[0062] Compared with the prior art, the highly oriented and dense ceramic provided by the present invention uses any two or more raw materials selected from small-particle-size highly oriented ceramic powder, large-particle-size highly oriented ceramic powder, and graphene oxide aqueous solution, such as a blend of small-particle-size highly oriented ceramic powder and large-particle-size highly oriented ceramic powder, or a blend of small-particle-size highly oriented ceramic powder and graphene oxide aqueous solution, or a blend of large-particle-size highly oriented ceramic powder, small-particle-size highly oriented ceramic powder, and graphene oxide aqueous solution; and finally, a binder is added, which can improve the orientation and density during the green body structure forming process, thereby enhancing the high orientation and excellent performance of the final obtained ceramic material.

[0063] It should be noted that the small-particle-size highly oriented ceramic powder and the large-particle-size highly oriented ceramic powder in this invention are selected from materials with orientation properties, such as one-dimensional fibrous or rod-shaped materials; and two-dimensional lamellar materials. For example, lamellar α-Al2O3, lamellar hexagonal boron nitride (hBN), etc.

[0064] Specifically, the mass ratio of small-particle-size highly oriented ceramic powder and / or large-particle-size highly oriented ceramic powder to binder is 100:(0-40), such as 100:1, 100:10, 100:20, 100:30 or 100:40.

[0065] It should be noted that the binder in this invention is used in conjunction with highly oriented ceramic powder to prepare ceramics, and the type of binder affects the properties of the final ceramic. When alumina is chosen as the binder, the resulting ceramic has high thermal conductivity; when mullite is chosen as the binder, the resulting ceramic has high hardness; when a mixture of alumina, magnesium oxide, and mullite is chosen as the binder, the resulting ceramic has both good thermal conductivity and high mechanical strength.

[0066] This invention allows for the selection of different binders based on the different application scenarios of ceramics, such as high thermal conductivity requirements and low mechanical performance requirements; or high requirements for both thermal conductivity and mechanical performance; or high mechanical performance requirements and low thermal conductivity requirements. The overall solution is simple and relatively flexible.

[0067] Furthermore, the mass ratio of small-particle-size highly oriented ceramic powder and / or large-particle-size highly oriented ceramic powder to the graphene oxide aqueous solution is 10:1-200:1, such as 10:1, 20:1, 40:1, 50:1, 70:1, 80:1, 100:1, 120:1, 150:1, 180:1 or 200:1.

[0068] Specifically, the graphene oxide sheet diameter in the aqueous solution of the graphene oxide is ≥5μm.

[0069] Specifically, the concentration of the graphene oxide aqueous solution is 0.5 mg / ml to 10 mg / ml, such as 0.5 mg / ml, 1.5 mg / ml, 2.5 mg / ml, 5 mg / ml, 7 mg / ml or 10 mg / ml.

[0070] It should be noted that during the preparation of ceramics, the addition of an aqueous solution of graphene oxide (GO solution) can reduce the van der Waals forces (repulsive forces) between highly oriented ceramic powders, optimize their arrangement structure, and make the highly oriented ceramic powder and binder more uniformly dispersed. Combined with vacuum filtration, the resulting ceramic surface structure is smoother, especially boron nitride ceramics.

[0071] When the mass of highly oriented ceramic powder is less than 10 times the mass of graphene oxide, the graphene content is too high, affecting the material's temperature resistance. When the mass of highly oriented ceramic powder is more than 200 times the mass of graphene oxide, the graphene content is too low, failing to regulate the ceramic arrangement structure and optimize its mechanical properties.

[0072] Specifically, the average particle size of the large-particle-size highly oriented ceramic powder is 10-30 times that of the small-particle-size highly oriented ceramic powder.

[0073] Specifically, the average particle size of the large-particle-size, highly oriented ceramic powder is between 80 and 500 μm.

[0074] It should be noted that in this invention, large-particle-size highly oriented ceramic powder and small-particle-size highly oriented ceramic powder can be blended, and the particle size and weight ratio of the large-particle-size highly oriented ceramic powder and the small-particle-size highly oriented ceramic powder can be further controlled and optimized. By filling the gaps between the large-particle-size highly oriented ceramic powder, the density of the ceramic is improved. The orientation preference of the large-particle-size highly oriented ceramic powder during the stacking process is utilized to optimize the orientation of the ceramic. Furthermore, the large-particle-size highly oriented ceramic powder can act as a "structural bridge" between the small-particle-size highly oriented ceramic powder and the binder, which greatly improves the mechanical strength of the ceramic.

[0075] Specifically, the mass ratio of the large-particle-size highly oriented ceramic powder to the small-particle-size highly oriented ceramic powder is 1:1 to 1:35.

[0076] Preferably, the average particle size of the large-particle-size, highly oriented ceramic powder can be 80μm, 120μm, 200μm, 350μm, or 500μm.

[0077] Preferably, the average particle size of the small-particle-size highly oriented ceramic powder can be 2μm, 8μm, 12μm, 25μm or 50μm.

[0078] This invention requires controlling the mass ratio of large-particle-size highly oriented ceramic powder to small-particle-size highly oriented ceramic powder, and controlling the mass of small-particle-size highly oriented ceramic powder to be 1-35 times that of large-particle-size highly oriented ceramic powder.

[0079] Preferably, the mass of the small-particle-size highly oriented ceramic powder is 1, 2, 4, 6, 10, 15, 18, 22, 25, 30, or 35 times that of the large-particle-size highly oriented ceramic powder.

[0080] Preferably, the mass of small-particle-size highly oriented ceramic powder is 1-10 times that of large-particle-size highly oriented ceramic powder.

[0081] According to simulation and experimental results, as the content of large-particle-size highly oriented ceramic powder decreases, the resulting orientation gradually decreases, and the larger the absolute value of IOP, the higher the material orientation.

[0082] Specifically, the binder consists of yttrium oxide, magnesium oxide, aluminum oxide, silicon dioxide, and mullite.

[0083] Specifically, the particle size of the binder is less than or equal to the average particle size of the selected small-particle-size highly oriented ceramic powder.

[0084] It should be noted that in this invention, the large-particle-size highly oriented ceramic powder serves as a bridge connecting the small-particle-size highly oriented ceramic powder and the binder, controlling the particle size of the binder to be less than or equal to the average particle size of the small-particle-size highly oriented ceramic powder. When the binder particle size is small, it can fill the gaps, increasing the density and strength of the final ceramic.

[0085] Furthermore, the preparation method of highly oriented and highly dense ceramic materials includes the following steps:

[0086] S1: Weigh out large-particle-size highly oriented ceramic powder and small-particle-size highly oriented ceramic powder according to the ratio and mix them with solvent respectively. The mixing ratio is 10g:1L.

[0087] Then, take any two or more of the following: the mixed large-particle-size highly oriented ceramic powder solution, the small-particle-size highly oriented ceramic powder solution, and the graphene oxide aqueous solution;

[0088] S2: Weigh out the adhesive additive according to the ratio and mix it with the solvent. The mixing ratio is 10g:1L.

[0089] S3: Mix the solutions prepared by S1 and S2, stir, and then use vacuum filtration to obtain a dry mixed powder block, and transfer the mixed powder block to a sintering mold;

[0090] S4: Place the mold in a heating furnace and dry it at 100-600℃ for 0.5-2 hours to obtain a ceramic green body;

[0091] S5: The obtained ceramic green body is sintered to obtain highly oriented and dense ceramic.

[0092] Compared with the prior art, the present invention uses a combination of large-particle-size highly oriented ceramic powder and small-particle-size highly oriented ceramic powder, which can improve the orientation of ceramic green bodies and the final ceramics; or, by adding an aqueous solution of graphene oxide to large-particle-size highly oriented ceramic powder and / or small-particle-size highly oriented ceramic powder, and using vacuum filtration, the orientation and performance of ceramic green bodies and the final ceramics can be improved.

[0093] Before sintering, the mixed powder blocks need to be dried at 100-600℃. When using an aqueous solution of graphene oxide, drying is carried out at 100-500℃ to avoid affecting the material composition. However, if there is residual aqueous solution of graphene oxide during the preparation process, drying at 500-600℃ for 0.5-1 hour is used. Graphene undergoes aerobic oxidation at temperatures above 500℃, converting into carbon dioxide and being released, thus removing the residual graphene oxide.

[0094] The method for preparing highly oriented ceramic materials according to the present invention results in a ceramic green body with lower porosity compared to ceramic powder green bodies prepared by traditional methods (pressing). Even under pressureless sintering conditions, the resulting ceramic still exhibits excellent properties, such as ultra-high in-plane thermal conductivity and ultra-high flexural strength. For example, when preparing alumina ceramics, the flexural strength is above 190.67 MPa; when preparing hexagonal boron nitride ceramics, the axial thermal conductivity is above 12.05 W / m·K, and the radial thermal conductivity is above 12.05 W / m·K.

[0095] Specifically, the solvent includes, but is not limited to, one or more of water, methanol, ethanol, ethylene glycol, isopropanol, butane, dimethylformamide, acetone, and tetrahydrofuran.

[0096] It should be noted that adding a solvent to the large-particle-size highly oriented ceramic powder and / or small-particle-size highly oriented ceramic powder in this invention can improve its dispersion and prevent agglomeration. For example, hBN disperses better in isopropanol than in water.

[0097] Specifically, in step S6, sintering is performed under pressure or without pressure, and the sintering temperature is 1750-2000℃.

[0098] Specifically, during pressure sintering, the pressure is 5MPa-40MPa.

[0099] On the other hand, the present invention provides a method for manufacturing a directional heat-equalizing composite honeycomb structure, comprising the following steps:

[0100] S1. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the lower skin.

[0101] S2. Using vacuum brazing or gas-shielded brazing, the honeycomb core is first welded to the lower skin.

[0102] S3. Fill the honeycomb core with the honeycomb core material mechanically and / or manually;

[0103] S4. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the upper skin.

[0104] S5. Weld the upper skin and the honeycomb core together to obtain a honeycomb structure;

[0105] S6. A ceramic-based, graphene-based, or silicon-based directional heat dissipation layer is prepared on the outer surface of the skin of the honeycomb structure by spraying, brazing, or bonding.

[0106] S7. After the final welding of the components is completed, the whole structure undergoes stabilization heat treatment.

[0107] Specifically, in step S1 or S4, the brazing filler metal is a thin strip produced by vacuum rapid quenching technology, and its composition is titanium-based, i.e., Ti-Zr-Cu-Ni. The thickness of the brazing filler metal layer is 0.01 to 3.5 mm, such as 0.01 mm, 0.05 mm, 0.1 mm, 1 mm, 1.5 mm, 2 mm, and 3 mm. During welding, the surface roughness Ra can be controlled within the range of 0.4 to 0.6. Appropriate roughness will obtain better capillary action, allowing the molten brazing filler metal to better wet the substrate, thereby improving the brazing quality.

[0108] Specifically, in step S2, the welding process is carried out in a vacuum diffusion brazing furnace at a temperature 33–60°C below the phase transformation temperature of the titanium-based alloy system, achieving a welding success rate of over 90%. Appropriate welding temperature ensures welding quality; too low a temperature may result in incomplete melting of the brazing filler metal, while too high a temperature can cause phase transformation in the matrix, damaging the overall structural performance.

[0109] Specifically, in step S3, individual silica fibers are made into clusters as core fillers and filled into the honeycomb core. During the filling process, the height and other dimensions of the filler are controlled to be 0.1 to 1 mm larger than the honeycomb core size, thereby reducing the relative sliding between the internal filler and the honeycomb structure. In other words, the size of the filler must be adapted to the internal size of the honeycomb grid.

[0110] Specifically, in step S5, the welding temperature is 450-1400℃, such as 600℃, 750℃, 900℃, 920℃, 930℃, 940℃, 960℃, 970℃, 1100℃, 1300℃, and the holding time is 20-60 minutes.

[0111] Specifically, in step S6, the spraying methods include flame spraying, plasma spraying, and cold spraying.

[0112] It should be noted that when spraying the directional heat-dissipating material onto the upper skin, the surface of the upper skin needs to be treated before spraying, and the roughness needs to be controlled within the range of 0.04 to 0.2. Then, the oil and small particles on the surface of the upper skin are cleaned by alkaline washing, and then uniform spraying is performed at a spraying temperature of 800 to 1200℃ (excluding cold spraying).

[0113] After spraying, a curing process is required to make the material and skin bond stronger. The curing temperature is 25-450℃ and the curing time is 0-180min.

[0114] In one possible implementation, a two-dimensional ceramic material is sprayed onto the TA15 panel using a cold spray method: before spraying, the TA15 panel is first sanded with 800# sandpaper to remove the oxide scale. During sanding, the roughness Ra is controlled within the range of 0.04 to 0.2. Then, the oil stains and small particles on the surface of the TA15 panel are cleaned using an alkaline washing method.

[0115] For graphene-based composite materials, the spraying material is a dispersion solution of graphene-based composite materials, wherein the dispersion is deionized water, and the mass concentration of the graphene-based composite material is 280–300 mg·L⁻¹. -1 Then, preheat the coating to 50℃ and spray it at a speed of 700mm / s. After spraying, a curing process is required to ensure a stronger and more reliable connection between the graphene-based composite material layer and the TA15 panel. The curing temperature is 150~450℃, and the curing time is 30min.

[0116] For graphene-based ceramic composites, graphene is dispersed in a dispersion medium to form a 5% graphene dispersion. SiO2 ceramic powder is then added to the graphene dispersion at a concentration of 280–350 mg·L⁻¹. -1The materials are thoroughly mixed. The spraying material is a dispersion of graphene and SiO2 ceramic powder, with deionized water as the dispersion medium. The powder particle size is 100–200 μm. Preheating is then performed at 60°C, followed by spraying at 800°C and a spraying speed of 500 mm / s. After spraying, a curing process is required to ensure a stronger and more reliable bond between the two-dimensional graphene-based ceramic composite layer and the TA15 panel. The curing temperature is 150–450°C, and the curing time is 30 minutes.

[0117] Specifically, in steps S1 and S4, when brazing is used, the brazing temperature is 800–960℃, the holding time is 10–45 min, and Ti-Zr-Cu-Ni type brazing filler is used.

[0118] Specifically, in step S6, when brazing is used, the brazing temperature is 800-960℃, the holding time is 10-45min, and Ti-Cu-Ag type brazing filler is used.

[0119] In one specific embodiment of the present invention, a 0.1 mm thick ceramic material is connected to an upper skin by brazing. First, the surface oxide film of the upper skin is removed by sanding with 800# sandpaper. A layer of uniformly ground Ti-Cu-Ag brazing filler powder is then laid on top. The oriented heat-spreading layer of the ceramic material is placed on the top layer, and a single-layer graphite pressure plate weighing 5 kg is used to apply load. Then, the material is placed in a vacuum brazing furnace at a vacuum degree of 8 × 10⁻⁶. -4 The welding temperature is 890℃, and the holding time is 15 minutes. Then the temperature is reduced to 800℃, held for 5 minutes, and then cooled in the furnace until it is removed from the furnace.

[0120] Specifically, in steps S1 and S6, when using the adhesive method, a high-temperature resistant inorganic adhesive is used. The adhesive is evenly applied to the bonding surface, left at room temperature for 2 to 12 hours, then kept at a temperature of 60 to 100°C for 1 to 4 hours, and then kept at 100 to 300°C for 2 hours to complete the bonding.

[0121] In one specific embodiment of the present invention, a high thermal conductivity graphene film is bonded to a TA15 panel using an adhesive method: the prepared high-temperature resistant inorganic adhesive is evenly applied between the TA15 panel and the graphene film with a thickness of 0.1 mm, and then left at room temperature for 2 hours, followed by a temperature of 60°C for 1 hour, and then a temperature of 100°C for 2 hours to complete the bonding.

[0122] Specifically, in step S7, the stabilization heat treatment temperature can be 20-100℃ lower than the welding temperature. During the welding process, in order to stabilize the weld structure, scanning electron microscopy can be used to ensure that the diffusion of each element is sufficient in each process of structural connection, while also achieving the effect of stress elimination.

[0123] To more clearly describe the present invention, the following embodiments and comparative examples are provided. All embodiments and comparative examples use a 1mm thick TA15 skin, a 0.1mm thick honeycomb core with a height of 10mm, and employ Ti-Zr-Cu-Ni brazing filler.

[0124] Example 1

[0125] A directional heat-equalizing composite honeycomb structure includes, from top to bottom, a directional heat-equalizing layer 3, an upper skin 11, a honeycomb core 2, a core filler 4, and a lower skin 12. The directional heat-equalizing layer 3 is a high thermal conductivity graphene film with a thickness of 0.1 mm. The upper skin 11 and the lower skin 12 are both 1 mm thick. The honeycomb core 2 has a height of 10 mm and an inscribed circle diameter of 10 mm. The core filler 4 is filled by volume according to the specific density.

[0126] Preparation of directional homogenized composite honeycomb structure:

[0127] The skin and one side of the honeycomb core were sanded with 1000# sandpaper to control the roughness within the range of 0.4 to 0.6. Then, the brazing filler metal (Ti-Zr-Cu-Ni) was spread evenly between them. Welding was completed under vacuum conditions. The welding process was 920℃ for 20 minutes, followed by stabilization heat treatment at 900℃ for 20 minutes to achieve a density of 0.8 g / cm³. 3 Silica fibers were filled into the honeycomb core, which was 10 mm high, with each fiber being 10.5 mm long and 20 μm in diameter. Next, the same welding process as the lower skin was used to weld it to the upper skin. A prepared high-temperature resistant inorganic adhesive was evenly applied between the TA15 panel and the 0.1 mm thick high thermal conductivity graphene film. The mixture was first left at room temperature for 2 hours, then kept at 60°C for 1 hour, and then at 100°C for 2 hours to complete the bonding. Finally, the entire assembly was stabilized at 150°C for 10 minutes.

[0128] Example 2

[0129] A directional heat-equalizing composite honeycomb structure includes, from top to bottom, a directional heat-equalizing layer 3, an upper skin 11, a honeycomb core 2, a core filler 4, and a lower skin 12. The directional heat-equalizing layer 3 is a graphene-based ceramic composite material with a thickness of 1 mm. The upper skin 11 and the lower skin 12 are both 1 mm thick. The honeycomb core 2 has a height of 10 mm and an inscribed circle diameter of 10 mm. The core filler 4 is filled by volume according to the specific density.

[0130] Preparation of directional homogenized composite honeycomb structure:

[0131] The skin and one side of the honeycomb core were sanded with 1000# sandpaper to increase roughness. Then, brazing filler metal (Ti-Zr-Cu-Ni) was spread evenly between them. Welding was completed in a vacuum brazing furnace at 940℃ for 40 minutes, followed by stabilization at 900℃ for 20 minutes, resulting in a final density of 0.8 g / cm³. 3 Silica-based fibers were filled into the honeycomb core, which was 10 mm high, with the silica fibers being 10.5 mm long and 20 μm in diameter. Next, the same welding process as the lower skin welding was used to weld it to the upper skin. The graphene-based ceramic composite material was uniformly sprayed onto the TA15 panel using flame spraying. Graphene was dispersed in a dispersion medium to form a 5% graphene dispersion. SiO2 ceramic powder was added to the graphene dispersion at a concentration of 280 mg·L⁻¹. -1 The materials were mixed evenly. The spraying material was a mixture of graphene and SiO2 ceramic powder dispersion, the dispersion medium was deionized water, the powder particle size was 100μm, the spraying speed was 500mm / s, the spraying temperature was 800℃, the thickness was 1mm, the curing temperature was 150℃, and the curing time was 30min. Finally, the entire mixture was stabilized at 400℃ for 10min.

[0132] Comparative Example 1

[0133] A honeycomb structure without a core filler and a directional heat dissipation layer includes an upper skin 11, a honeycomb core 2, and a lower skin 12 arranged sequentially from top to bottom. The thickness of the upper skin 11 and the lower skin 12 is 1 mm, and the honeycomb core 2 has a height of 10 mm and an inscribed circle diameter of 10 mm.

[0134] Fabrication of a honeycomb structure without a core filler and a directional heat dissipation layer:

[0135] Grind one side of the lower skin and honeycomb core with 800# sandpaper to control the roughness within the range of 0.4 to 0.6. Then, spread the brazing filler metal between the two. The brazing filler metal is Ti-Zr-Cu-Ni. Welding is completed under vacuum conditions. The welding process is 920℃ for 20 minutes. Then, it is stabilized by heat treatment at 900℃ for 20 minutes. Next, the same welding process as when welding the lower skin is used to complete the welding with the upper skin.

[0136] Table 1 Back temperature experiment results

[0137] Example Example 1 Example 2 Comparative Example 1 cold surface temperature 393.8℃ 395.2℃ 454.8℃ The difference between the and the comparative proportions 61.0℃ 59.6℃ /

[0138] Example 3

[0139] A directional heat-equalizing composite honeycomb structure includes, from top to bottom, a directional heat-equalizing layer 3, an upper skin 11, a honeycomb core 2, a core filler 4, and a lower skin 12. The directional heat-equalizing layer 3 is made of ceramic material and has a thickness of 0.1 mm. The upper skin 11 and the lower skin 12 are both 1 mm thick. The honeycomb core 2 has a height of 10 mm and an inscribed circle diameter of 10 mm. The core filler 4 is filled by volume according to the specific density.

[0140] Preparation of directional homogenized composite honeycomb structure:

[0141] The skin and one side of the honeycomb core were sanded with 800# sandpaper to control the roughness within the range of 0.4 to 0.6. Then, the brazing filler metal (Ti-Zr-Cu-Ni) was spread evenly between them. Welding was completed under vacuum conditions. The welding process was 920℃ for 20 minutes, followed by stabilization heat treatment at 900℃ for 20 minutes to achieve a density of 0.8 g / cm³. 3 Silica fibers were filled into the honeycomb core, which was 10 mm high. The silica fibers were 10.5 mm long and 20 μm in diameter. Next, the same welding process as the lower skin was used to weld it to the upper skin. A 0.1 mm thick ceramic material was connected to the upper skin using brazing. Specifically, the surface oxide film of the upper skin was first removed by sanding with 800# sandpaper, a layer of uniformly ground Ti-Cu-Ag brazing filler powder was spread, the oriented heat-spreading layer of the ceramic material was placed on top, and a single-layer 5 kg graphite pressure plate was used to apply load. Then, the furnace was placed in a vacuum brazing furnace at a vacuum degree of 8 × 10⁻⁶. -4 The welding temperature is 890℃, and the holding time is 15 minutes. Then the temperature is reduced to 800℃, held for 5 minutes, and then cooled in the furnace until it is removed from the furnace.

[0142] In the above-mentioned directional homogenized composite honeycomb structure, there are various methods for preparing ceramic materials. To describe this more clearly, the following examples and comparative examples of ceramic material preparation are provided for further explanation.

[0143] Preparation Example 1

[0144] This preparation example provides a method for preparing a highly oriented hexagonal boron nitride ceramic material, including the following steps:

[0145] Weigh out 8g of large-particle-size plate-shaped hexagonal boron nitride ceramic powder (average particle size 250μm) and 12g of small-particle-size plate-shaped hexagonal boron nitride ceramic powder (average particle size 10μm) according to the proportion; a total of 20g of oriented ceramic powder is added and mechanically stirred for 1 hour with 2L of ethanol.

[0146] Add 40 ml of graphene oxide (GO) aqueous solution (5 mg / ml) and continue mechanical stirring for 2 hours.

[0147] The above mixed solution was vacuum filtered to obtain a dry mixed powder block, which was then transferred to a sintering mold. The mold was placed in a muffle furnace and dried at 550°C for 2 hours under an air atmosphere to obtain boron nitride ceramic green body. Then, it was hot-pressed and sintered (1900°C, 30MPa, 1h) to obtain hexagonal boron nitride ceramic.

[0148] Preparation Examples 2-10, Comparative Examples 2-3

[0149] The differences between Preparation Examples 2-10, Comparative Examples 2-3 and Preparation Example 1 are shown in Table 2. The hexagonal boron nitride ceramics obtained from Preparation Examples 1-10 and Comparative Examples 2-3 were tested for performance, and the test results are shown in Table 3.

[0150] Table 2. Parameters that differentiate the preparation examples from the comparative examples.

[0151] Group Large particle size / g Small particle size / g GO solution / ml Preparation Example 1 8 12 0 Preparation Example 2 4 16 0 Preparation Example 3 2 18 0 Preparation Example 4 8 12 40 Preparation Example 5 4 16 40 Preparation Example 6 2 18 40 Preparation Example 7 8 12 80 Preparation Example 8 8 12 200 Preparation Example 9 0 20 40 Preparation Example 10 20 0 40 Comparative Example 2 0 20 0 Comparative Example 3 20 0 0

[0152] Table 3 Detection Results

[0153]

[0154]

[0155] As can be seen from the preparation examples 1-6 and in conjunction with Tables 2 and 3, when an aqueous solution of graphene oxide is added to large-particle-size and / or small-particle-size highly oriented ceramic powders, the IOP and thermal conductivity of the resulting hexagonal boron nitride ceramics increase, and the density gradually increases. This indicates that the aqueous solution of graphene oxide can improve the orientation, thermal conductivity, and density of hexagonal boron nitride ceramics.

[0156] By preparing Examples 1-3 and combining Figure 3-5 It can be seen that without the addition of GO solution, the orientation arrangement structure of hexagonal boron nitride ceramics is optimized with the increase of the content of large flakes.

[0157] By preparing Examples 1, 6-8 and combining Figure 5-8 It can be seen that when the weights of large-particle-size highly oriented ceramic powder and small-particle-size highly oriented ceramic powder remain unchanged, the orientation arrangement structure of hexagonal boron nitride ceramic is optimized with the increase of GO solution content.

[0158] Preparation of directional homogenized composite honeycomb structure:

[0159] The ceramic materials prepared in Examples 1 to 10 were respectively applied to the directional homogenized composite honeycomb structure in Example 3.

[0160] Performance testing: Back temperature test. One side of the honeycomb surface of the directional heat-spreading layer in Preparation Examples 1 to 10 and the honeycomb in Comparative Example 1 was heated to 700°C, and the temperature of the other side was tested. The results showed that, compared with the honeycomb structure of the Comparative Example without core filling and directional heat-spreading layer, the cold surface temperature of the honeycomb structure with directional heat-spreading layer used in Preparation Examples 1 to 10 was at least 60°C lower than the cold surface temperature of 454.8°C measured in Comparative Example 1, and it had better heat resistance.

[0161] One of the ceramic materials prepared in Examples 1-10 was selected and applied to the directional homogenized honeycomb structure in Example 3. A highly oriented hexagonal boron nitride ceramic material prepared in Example 1 was chosen. Its processing is simple, eliminating the need for adding graphene oxide (GO) aqueous solution, and its thermal conductivity test results were also good. Its radial thermal conductivity was 153.21 W / m·K, meaning the heat flow per unit area and unit temperature difference in the radial direction was 153.21 W. This value is relatively high, indicating good thermal conductivity in the radial direction. Its axial thermal conductivity was 13.27 W / m·K, meaning the heat flow in the axial direction under the same conditions was only 13.27 W. This value is much lower than the radial thermal conductivity, indicating weaker thermal conductivity in the axial direction. The material exhibits significant differences in thermal conductivity in different directions and can be considered a "directional homogenized material."

[0162] Performance testing: Back temperature test results are as follows Figure 2 As shown, one side of the honeycomb surface of the oriented heat-equalizing layer prepared with ceramic material of Example 1 in Example 3 and the honeycomb in Comparative Example 1 were heated to 700°C, and the temperature of the other side (cold side) was tested. It can be seen that, compared with the honeycomb of the comparative example without core filling and oriented heat-equalizing layer, the cold side temperature measured in Example 3 using the oriented heat-equalizing layer prepared with ceramic material of Example 1 was 387.9°C, which is 66.9°C lower than the cold side temperature of 454.8°C measured in the comparative example, indicating better heat resistance.

[0163] The higher the thermal conductivity (W / m·K), the better the thermal conductivity. In Example 3, when the directional heat-spreading layer of the ceramic material prepared in other examples was used, the difference between the cold surface temperature of 454.8℃ measured in the comparative example and the temperature of 70-75℃ was 70-75℃, indicating better heat resistance.

[0164] The directional heat-equalizing honeycomb structure described in this invention has an outermost directional heat-equalizing layer that can largely prevent heat accumulation on the surface and conduct heat laterally to the low-temperature region, reducing the effective heat input per unit area in the heat-concentrated area of ​​the honeycomb surface. The core filling material inside the honeycomb can effectively hinder heat transfer through conduction and radiation within the honeycomb, increasing the heat capacity of the honeycomb structure. This reduces the effective heat transfer from the hot end to the cold end of the honeycomb, effectively achieving secondary control of the introduced heat and preventing overheating failure of the protected device due to excessive heat introduction.

[0165] The directional heat-equalizing honeycomb structure of the present invention not only meets the current trend of lightweight development, but also effectively improves the heat resistance / insulation of the honeycomb structure and enhances the safety of the protected devices inside the honeycomb. It has the advantages of being lightweight, heat-resistant, and having high insulation capabilities.

[0166] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A directional heat-equalizing composite honeycomb structure, characterized in that, It includes, from top to bottom, a directional heat dissipation layer, an upper skin, a honeycomb core and core filler, and a lower skin; the directional heat dissipation layer is made of a two-dimensional material matrix, including one of a highly oriented and dense ceramic material, a high thermal conductivity graphene film, a graphene-based composite material, and a graphene-based ceramic composite material, with a thickness of 0.01 to 10 mm. The highly oriented and dense ceramic material is prepared by selecting any two or more raw materials from small-particle-size highly oriented ceramic powder, large-particle-size highly oriented ceramic powder and graphene oxide aqueous solution, as well as a binder. The mass ratio of small-particle-size highly oriented ceramic powder and / or large-particle-size highly oriented ceramic powder to graphene oxide aqueous solution is 10:1-200:1; the mass ratio of large-particle-size highly oriented ceramic powder to small-particle-size highly oriented ceramic powder is 1:1-1:35; the average particle size of the large-particle-size highly oriented ceramic powder is 10-30 times that of the small-particle-size highly oriented ceramic powder; the average particle size of the large-particle-size highly oriented ceramic powder is 80-500 μm. The small-particle-size highly oriented ceramic powder and the large-particle-size highly oriented ceramic powder are selected from α-Al2O3, hBN, SiC, layered molybdate, Si3N4 and SiO2, and the binder is selected from yttrium oxide, magnesium oxide, aluminum oxide, silicon dioxide and mullite; The preparation of highly oriented and dense ceramics involves mixing small-particle-size highly oriented ceramic powder and large-particle-size highly oriented ceramic powder with an aqueous solution of graphene oxide; adding a binder and then vacuum filtering; drying and then sintering under pressure or pressure.

2. The directional homogenizing composite honeycomb structure according to claim 1, characterized in that, The upper skin is made of either a titanium-based or nickel-based alloy, with a thickness of 0.1 mm to 20 mm.

3. The directional homogenized heat-dissipating composite honeycomb structure according to claim 1, characterized in that, The lower skin is made of either a titanium-based or nickel-based alloy, with a thickness of 0.1 mm to 20 mm.

4. The directional homogenizing composite honeycomb structure according to claim 1, characterized in that, The honeycomb core is a honeycomb-like mesh structure with a thickness of 0.01–3 mm and a height of 1–50 mm, and is made of titanium alloy.

5. The directional homogenizing composite honeycomb structure according to claim 1, characterized in that, The core filler has a density of less than 1 g / cm³. 3 One of silicon-based fibers, silicon-based aerogels, or graphene aerogels.

6. A method for manufacturing a directional homogenized composite honeycomb structure, used to prepare the directional homogenized composite honeycomb structure as described in any one of claims 1-5, comprising the following steps: S1. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the lower skin. S2. Using vacuum brazing or gas-shielded brazing, the honeycomb core is first welded to the lower skin. S3. Fill the honeycomb core with the honeycomb core material mechanically and / or manually; S4. Perform surface treatment by spreading or brushing one or more layers of brazing filler on the upper skin. S5. Weld the upper skin and the honeycomb core together to obtain a honeycomb structure; S6. A two-dimensional material-based oriented heat-equalizing layer is prepared on the outer surface of the skin of the honeycomb structure by spraying, brazing, or bonding; the oriented heat-equalizing layer is made of one of the following: highly oriented and dense ceramic material, high thermal conductivity graphene film, graphene-based composite material, and graphene-based ceramic composite material; the preparation of the highly oriented and dense ceramic material includes the following steps: (1) Weigh out large-particle-size highly oriented ceramic powder and small-particle-size highly oriented ceramic powder according to the ratio and mix them with solvent respectively. The mixing ratio is 10g:1L. Then, take any two or more of the following: the mixed large-particle-size highly oriented ceramic powder solution, the small-particle-size highly oriented ceramic powder solution, and the graphene oxide aqueous solution; (2) Weigh out the adhesive additive according to the ratio and mix it with the solvent. The mixing ratio is 10g:1L. (3) Mix the mixed solutions prepared in step (1) and (2), stir, and then use vacuum filtration to obtain dry mixed powder blocks, and transfer the mixed powder blocks to a sintering mold; (4) Place the mold in a heating furnace and dry it at 100-600℃ for 0.5-2 hours to obtain a ceramic green body; (5) The obtained ceramic green body is sintered to obtain highly oriented and dense ceramic. S7. After the final welding of the components is completed, the whole structure undergoes stabilization heat treatment.

7. The manufacturing method according to claim 6, characterized in that, In step S1 or S4, the thickness of the solder layer is 0.01 to 3.5 mm.

8. The manufacturing method according to claim 6, characterized in that, In step S5, the welding temperature is 450–1400℃ and the holding time is 20–60 min.

9. The manufacturing method according to claim 6, characterized in that, In step S7, the heat treatment temperature is 20-100°C lower than the welding temperature.

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