Heat dredging device of aircraft and preparation method of heat dredging device

Abstract

The invention relates to the field of heat dredging devices, in particular to a heat dredging device of an aircraft and a preparation method thereof.The heat dredging device comprises an anti-oxidation layer, a carbon / carbon composite material heat conduction layer, an oscillating heat pipe layer, a composite graphene heat conduction layer and an inorganic heat insulation foam layer which are arranged from outside to inside; the anti-oxidation layer comprises an aluminum modified transition alloy layer and a nano-structure ceramic layer sprayed on the surface of the aluminum modified transition alloy layer; the composite graphene heat-conducting layer is prepared from the following raw materials in parts by weight: 10-30 parts of copper foil strips, 10-30 parts of heat-conducting glue and 10-30 parts of graphene films; and the inorganic heat insulation foam layer is made of a foam material. The heat dredging device prepared by the preparation method provided by the invention has high temperature resistance.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of heat dissipation devices, in particular to a heat dissipation device of an aircraft and a preparation method thereof. BACKGROUND

[0002] The development of modern aircraft is changing towards informatization, miniaturization and integration, and the increase of power density of the equipment in the electronic cabin of the aircraft puts higher requirements on the heat dissipation of the electronic cabin of the aircraft. Therefore, the aircraft needs a device cabin heat dissipation device to maintain the normal operation of the aircraft. The existing heat dissipation devices are mainly based on radiation, heat conduction and natural convection for heat dissipation, and are generally composed of heat dissipation fins, air inlets, air outlets, heat sinks and the like. The existing heat dissipation devices have the problem of poor high-temperature resistance. SUMMARY

[0003] In view of the above problems, the present application aims to provide a heat dissipation device of an aircraft with good high-temperature resistance and a preparation method thereof.

[0004] The present application solves the technical problem by providing a heat dissipation device of an aircraft, which comprises, from the outside to the inside, an oxidation-resistant layer, a carbon / carbon composite heat-conducting layer, an oscillating heat pipe layer, a composite graphene heat-conducting layer and an inorganic heat-insulating foam layer.

[0005] The oxidation-resistant layer comprises an aluminum-modified transition alloy layer and a nano-structured ceramic layer arranged on the surface of the aluminum-modified transition alloy layer.

[0006] The aluminum-modified transition alloy layer is composed of the following raw materials by weight: 1-3 parts of chromium-manganese alloy, 1-3 parts of nickel-magnesium alloy and 1-3 parts of Fe-Mn-Si-based alloy.

[0007] The nano-structured ceramic layer is composed of the following raw materials by weight: 1-3 parts of zirconia ceramic, 1-3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1-3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2.

[0008] The composite graphene heat-conducting layer is composed of the following raw materials by weight: 10-30 parts of copper foil strips, 10-30 parts of heat-conducting glue and 10-30 parts of graphene film.

[0009] The inorganic heat-insulating foam layer is made of foam material.

[0010] Further, the thickness of the aluminum-modified transition alloy layer is 30-35 microns, and the thickness of the nano-structured ceramic layer is 90-95 microns.

[0011] Further, the carbon / carbon composite material is composed of the following raw materials by weight parts: 60-90 parts of heat-conducting carbon fiber three-dimensional woven solid structure, 50-80 parts of liquid crystal material, and 1-5 parts of graphene nanosheet.

[0012] Further, the copper foil strip is surface modified by Cu3N.

[0013] The heat-conducting glue is any one of graphene-reinforced heat-conducting silica gel, foam copper-reinforced heat-conducting silica gel, epoxy resin doped with AlN and BN particles.

[0014] Further, the foam material is any one of SiBCN foam material, SiHfBCN foam material, SiBCN / C composite foam material and SiHfBCN / C composite foam material.

[0015] Further, the oxidation-resistant layer, the carbon / carbon composite material heat-conducting layer, the oscillating heat pipe layer, the composite graphene heat-conducting layer and the inorganic heat-insulating foam layer are all in a bent strip structure with pointed ends at both ends.

[0016] The application also provides a preparation method of the heat dissipation device of the aircraft, comprising the following steps:

[0017] Step 1. Preparation of the oxidation-resistant layer:

[0018] Step 1.1. 1-3 parts of chromium-manganese alloy, 1-3 parts of nickel-magnesium alloy and 1-3 parts of Fe-Mn-Si-based alloy are weighed by weight parts, mixed, loaded into a reaction container, compacted, covered, placed into an atmosphere furnace, vacuumized, pumped, pyrolyzed at 150-200 DEG C for 0.5-1.5 h, cooled to room temperature, taken out, carbonized at 500-700 DEG C for 2-3 h, ground into powder, added with aluminum chloride solution with a concentration of 0.5-2.0 mol / L, ultrasonically vibrated, placed, filtered, washed until no chloride ions are precipitated, dried at 70-100 DEG C for 1-3 h, and then the aluminum-modified alloy powder is obtained, which is pressed into an aluminum-modified transition alloy layer with a thickness of 30-35 mu m in a mold blank;

[0019] Step 1.2. 1-3 parts of zirconia ceramic, 1-3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1-3 parts of ZrB2-20SiC ultrahigh-temperature ceramic modified by MoSi2 and TaSi2 are weighed by weight parts to obtain mixed ceramic powder B.

[0020] Step 1.3. Micro-arc oxidation is performed on the surface of the aluminum modified transition alloy layer. The electrolyte composition for micro-arc oxidation is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The electrolyte temperature is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply with a positive voltage of 0–400V, a negative voltage of 0–800V, a positive open area ratio of 50%, a negative open area ratio of 50%, and a positive current density of 2 A / cm². 2 Negative current density 1 A / cm 2 The voltage frequency was 400 Hz, the oxidation time was 30 min, the temperature of the aluminum modified transition alloy layer after micro-arc oxidation was heated to the melting point of ultra-high temperature ceramics and maintained at this temperature, and the mixed ceramic powder B obtained in step 1.2 was placed on its surface.

[0021] Step 1.4. Open the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder B and the aluminum modified transition alloy layer to make them fit tightly. After the ultrasonic head presses for 3 seconds, maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply, the ultrasonic power is 1500W, the ultrasonic frequency is 20kHz, and the duration is 1.5s.

[0022] Step 1.5. Obtain a nanostructured ceramic layer bonded to the aluminum-modified transition alloy layer. The thickness of the nanostructured ceramic layer is 90-95 μm. Air-cooled until the interface is completely solidified.

[0023] Step 2. Prepare a carbon / carbon composite thermally conductive layer:

[0024] Weigh 50-80 parts of liquid crystal material and 1-5 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 60-90 parts of thermally conductive carbon fiber three-dimensional woven structure according to weight to impregnate mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain a carbon / carbon composite thermally conductive layer.

[0025] Step 3. Prepare the composite graphene thermally conductive layer:

[0026] Step 3.1. Weigh out 10-30 parts by weight of copper foil strips, 10-30 parts of thermally conductive adhesive, 10-30 parts of graphene film, and coal tar powder. Layer these components alternately in a mold in the following order: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. Place the mold on a hot press at 200℃ and 5MPa to form a composite. After holding the temperature and pressure for 0.5 hours, allow it to cool naturally to obtain a preform. Carbonize the preform (without removing it from the mold) at 1000℃. After cooling, remove it and repeatedly sprinkle coal tar powder into a stainless steel mold. Low-density carbon / carbon composite material was obtained by hot pressing and carbonization five times. Using acetylene as the carbon source, the low-density carbon / carbon composite material was deposited at 1100℃ for 400h to obtain medium-density carbon / carbon composite material. The medium-density carbon / carbon composite material was impregnated with molten coal-based mesophase pitch with a residual carbon rate of 65% under a pressure of 5MPa and carbonized at 1200℃. This process was repeated seven times to obtain high-density carbon / carbon composite material. The high-density carbon / carbon composite material was graphitized at 2800℃ in an inert gas for 2h and then naturally cooled to obtain a bidirectional high thermal conductivity carbon / carbon composite material.

[0027] Step 3.2. The bidirectional high thermal conductivity carbon-carbon composite material obtained in step 3.1 is molded with graphene film. The cavity in the mold is filled with asphalt and carbon powder. Under vacuum conditions, it is pre-pressed at 10 MPa and then placed in a sintering furnace. It is sintered at 50 MPa and 600℃ for 5 min, and then sintered at 900℃ and 100 MPa for 5 min. After cooling, a composite graphene thermal conductive layer is obtained.

[0028] Step 4: Prepare the inorganic thermal insulation foam layer:

[0029] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. Foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic heat insulation foam layer.

[0030] Step 5: Preparation of thermally conductive materials:

[0031] The antioxidant layer obtained in step (1), the carbon / carbon composite thermal conductive layer obtained in step (2), the oscillating heat pipe layer, the composite graphene thermal conductive layer obtained in step (3), and the inorganic thermal insulation foam layer prepared in step (4) are bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. When bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, and then an appropriate amount of thermal conductive grease is placed on the mesh plate. The thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. The thermal conductive tape is attached around each layer of thermal conductive grease to bond the layers together.

[0032] Furthermore, in step 1.1 above, the heating rate during pyrolysis is 10℃ / min, the heating rate during carbonization is 5℃ / min, the ultrasonic vibration time is 3-6h, and the settling time is 30min.

[0033] Furthermore, the air cooling rate in step 1.5 above is 20℃ / s.

[0034] Furthermore, in step 3.2 above, the heating rate during both sintering processes is 100℃ / min, and the cooling rate between 900℃ and 500℃ is 10℃ / min, with the furnace cooling from 500℃ to room temperature.

[0035] The beneficial effects of this invention are as follows: the heat conduction device prepared by the preparation method provided by this invention has good high temperature resistance. The antioxidant layer of the device contains an antioxidant and corrosion-resistant nanostructured ceramic layer. Both the antioxidant layer and the oscillating heat pipe layer of the device contain high temperature resistant alloys. Both the carbon / carbon composite heat conduction layer and the composite graphene heat conduction layer contain high temperature resistant graphite materials. Therefore, the device is corrosion resistant and can be used normally under high temperature and high pressure environments. At the same time, the composite graphene heat conduction layer in the device greatly improves its heat dissipation performance, and the overall heat dissipation performance of the device is good. Attached Figure Description

[0036] Figure 1 This is an exploded view of the overall structure of the present invention;

[0037] Figure 2 The TG curves for Examples 1-6 are shown below.

[0038] The corresponding names of the reference numerals in the above figures are: 1-antioxidant layer, 2-carbon / carbon composite thermal conductive layer, 3-oscillating heat pipe layer, 4-composite graphene thermal conductive layer, 5-inorganic thermal insulation foam layer, 6-bend. Specific Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0040] like Figure 1 As shown, the heat conduction device provided by the present invention includes an anti-oxidation layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside, wherein each layer is a bent strip structure with pointed ends.

[0041] The following embodiments use the following liquid crystal material: SLC1717; graphene nanosheets: XF011; graphene film: WJCOSA; thermally conductive tape: XK-T12; thermally conductive silicone grease: TG-235-CB; oscillating heat pipe: SE heat pipe heat exchanger, which was already arranged into an oscillating heat pipe layer at the time of purchase; the thermal conductivity of the three-dimensional woven thermally conductive carbon fiber structure is between 300 and 800 W / mK; the thickness of the copper foil strip is between 25 and 50 μm; the diameter of Cu3N is between 20 and 60 μm; the thickness of the graphene film is between 70 and 300 μm, and the thermal conductivity is between 900 and 1500 W / m·K.

[0042]

Example 1

[0043] (1) Preparation of antioxidant layer 1:

[0044] ① Weigh out 1 part chromium-manganese alloy, 1 part nickel-magnesium alloy, and 1 part Fe-Mn-Si based alloy by weight, mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 150℃ at 10℃ / min and hold for 1.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 700℃, the heating rate to 5℃ / min, and hold for 3h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 2.0mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 6h followed by 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 100℃ for 3h. The resulting aluminum-modified alloy powder is pressed into an aluminum-modified transition alloy layer with a thickness of 35μm in a mold blank.

[0045] ② Weigh out 2 parts by weight of zirconium oxide ceramic, 2 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 2 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0046] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2Voltage frequency 400Hz, oxidation time 30min;

[0047] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0048] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 95μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0049] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0050] Weigh 65 parts of liquid crystal material and 5 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 75 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0051] (3) Preparation of composite graphene thermal conductive layer 4:

[0052] Weigh out 20 parts by weight of Cu3N surface-modified copper foil strips, 20 parts of graphene-reinforced thermally conductive silicone, 20 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding the temperature and pressure for 0.5h, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0053] (4) Prepare inorganic thermal insulation foam layer 5:

[0054] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. The SiHfBCN / C composite foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0055] (5) Preparation of thermally conductive materials:

[0056] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0057] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0058]

Example 2

[0059] (1) Preparation of antioxidant layer 1:

[0060] ① Weigh out 1 part chromium-manganese alloy, 1 part nickel-magnesium alloy, and 1 part Fe-Mn-Si based alloy by weight, mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove it. During the pyrolysis process, first raise the temperature to 150℃ at 10℃ / min and hold for 0.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 500℃, the heating rate to 5℃ / min, and hold for 2h. Grind into powder. Prepare an aluminum chloride solution (concentration 0.5mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 3h and 30min. Filter, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 70℃ for 1h. After drying, obtain aluminum-modified alloy powder. Press it into an aluminum-modified transition alloy layer with a thickness of 30μm in a mold blank.

[0061] ② Weigh out 1 part by weight of zirconium oxide ceramic, 1 part of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1 part of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0062] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 0V, a negative voltage of 0V, a positive empty percentage of 50%, a negative empty percentage of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0063] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0064] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 90μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0065] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0066] Weigh 60 parts of liquid crystal material and 1 part of graphene nanosheets according to weight to prepare mixed solution A. Weigh 60 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0067] (3) Preparation of composite graphene thermal conductive layer 4:

[0068] Weigh out 10 parts by weight of Cu3N surface-modified copper foil strips, 10 parts of graphene-reinforced thermally conductive silicone, 10 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press to form a composite. After holding the heat and pressure for 0.5 hours, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0069] (4) Prepare inorganic thermal insulation foam layer 5:

[0070] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. Introduce SiBCN foam material onto the main circumferential surface of the tool roller and extrude it from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0071] (5) Preparation of thermally conductive materials:

[0072] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0073] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0074]

Example 3

[0075] (1) Preparation of antioxidant layer 1:

[0076] ① Weigh out 2 parts by weight of chromium-manganese alloy, 2 parts by weight of nickel-magnesium alloy, and 2 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 175℃ at 10℃ / min and hold for 1 hour to ensure uniform heating of the raw materials. Set the carbonization temperature to 600℃, the heating rate to 5℃ / min, and the holding time to 2.5 hours. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 1 mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then allow it to stand for 4.5 hours followed by 30 minutes. Filter the mixture, wash it with distilled water until no chloride ions are precipitated, and dry it in a drying oven at 85℃ for 2 hours. After drying, obtain aluminum-modified alloy powder. Press this powder into an aluminum-modified transition alloy layer with a thickness of 32 μm in a mold blank.

[0077] ② Weigh out 1 part by weight of zirconium oxide ceramic, 1 part of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1 part of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0078] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 200V, a negative voltage of 400V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0079] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0080] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 92μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0081] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0082] Weigh 50 parts of liquid crystal material and 1 part of graphene nanosheets according to weight to prepare mixed solution A. Weigh 60 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0083] (3) Preparation of composite graphene thermal conductive layer 4:

[0084] Weigh out 10 parts by weight of Cu3N surface-modified copper foil strips, 10 parts of copper foam-reinforced thermally conductive silicone, 10 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding the temperature and pressure for 0.5h, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0085] (4) Prepare inorganic thermal insulation foam layer 5:

[0086] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. Introduce SiHfBCN foam material onto the main circumferential surface of the tool roller and extrude it from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0087] (5) Preparation of thermally conductive materials:

[0088] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0089] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0090]

Example 4

[0091] (1) Preparation of antioxidant layer 1:

[0092] ① Weigh out 3 parts by weight of chromium-manganese alloy, 3 parts by weight of nickel-magnesium alloy, and 3 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 200℃ at 10℃ / min and hold for 1.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 700℃, the heating rate to 5℃ / min, and hold for 3h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 2.0mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 6h followed by 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 70-100℃ for 3h. After drying, obtain aluminum-modified alloy powder. Press this powder into an aluminum-modified transition alloy layer with a thickness of 33μm in a mold blank.

[0093] ② Weigh out 1 part by weight of zirconium oxide ceramic, 1 part of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1 part of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0094] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0095] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0096] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 93μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0097] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0098] Weigh 65 parts of liquid crystal material and 2 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 75 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0099] (3) Preparation of composite graphene thermal conductive layer 4:

[0100] Weigh out 10 parts by weight of Cu3N surface-modified copper foil strips, 10 parts of epoxy resin doped with AlN and BN particles, 10 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding at temperature and pressure for 0.5h, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0101] (4) Prepare inorganic thermal insulation foam layer 5:

[0102] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. The SiBCN / C composite foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0103] (5) Preparation of thermally conductive materials:

[0104] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0105]

Example 5

[0106] (1) Preparation of antioxidant layer 1:

[0107] ① Weigh out 3 parts by weight of chromium-manganese alloy, 3 parts by weight of nickel-magnesium alloy, and 3 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 200℃ at 10℃ / min and hold for 1.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 700℃, the heating rate to 5℃ / min, and hold for 3h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 2.0mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 6h followed by 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 100℃ for 3h. After drying, obtain aluminum-modified alloy powder. Press this powder into an aluminum-modified transition alloy layer with a thickness of 35μm in a mold blank.

[0108] ② Weigh out 3 parts by weight of zirconium oxide ceramic, 3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0109] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0110] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0111] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 95μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0112] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0113] Weigh 80 parts of liquid crystal material and 3 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 90 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0114] (3) Preparation of composite graphene thermal conductive layer 4:

[0115] Weigh out 15 parts by weight of Cu3N surface-modified copper foil strips, 15 parts of graphene-reinforced thermally conductive silicone, 10 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding the temperature and pressure for 0.5 hours, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0116] (4) Prepare inorganic thermal insulation foam layer 5:

[0117] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. The SiHfBCN / C composite foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0118] (5) Preparation of thermally conductive materials:

[0119] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0120] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0121]

Example 6

[0122] (1) Preparation of antioxidant layer 1:

[0123] ① Weigh out 3 parts by weight of chromium-manganese alloy, 3 parts by weight of nickel-magnesium alloy, and 3 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 150℃ at 10℃ / min and hold for 0.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 500℃, the heating rate to 5℃ / min, and hold for 2h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 0.5mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 3h and 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 70℃ for 1h. After drying, obtain aluminum-modified alloy powder. Press this powder into an aluminum-modified transition alloy layer with a thickness of 35μm in a mold blank.

[0124] ② Weigh out 3 parts by weight of zirconium oxide ceramic, 3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0125] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0126] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0127] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 90μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0128] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0129] Weigh 80 parts of liquid crystal material and 3 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 90 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0130] (3) Preparation of composite graphene thermal conductive layer 4:

[0131] Weigh out 30 parts by weight of Cu3N surface-modified copper foil strips, 30 parts of graphene-reinforced thermally conductive silicone, copper foam-reinforced thermally conductive silicone, epoxy resin doped with AlN and BN particles, and 30 parts of graphene film and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size in the following order: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding at temperature and pressure for 0.5h, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃, cool it, and then repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0132] (4) Prepare inorganic thermal insulation foam layer 5:

[0133] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. The SiHfBCN / C composite foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0134] (5) Preparation of thermally conductive materials:

[0135] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0136] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0137]

Example 7

[0138] (1) Preparation of antioxidant layer 1:

[0139] ① Weigh out 3 parts by weight of chromium-manganese alloy, 2 parts by weight of nickel-magnesium alloy, and 3 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 200℃ at 10℃ / min and hold for 1.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 700℃, the heating rate to 5℃ / min, and hold for 3h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 2.0mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 6h followed by 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 100℃ for 3h. The resulting aluminum-modified alloy powder is then pressed into an aluminum-modified transition alloy layer with a thickness of 30μm in a mold blank.

[0140] ② Weigh out 3 parts by weight of zirconium oxide ceramic, 3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0141] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0142] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0143] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 90μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0144] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0145] Weigh 70 parts of liquid crystal material and 3 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 90 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0146] (3) Preparation of composite graphene thermal conductive layer 4:

[0147] Weigh out 30 parts by weight of Cu3N surface-modified copper foil strips, 30 parts of graphene-reinforced thermally conductive silicone, 10 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press composite molding. After holding the temperature and pressure for 0.5h, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0148] (4) Prepare inorganic thermal insulation foam layer 5:

[0149] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. Introduce SiBCN foam material onto the main circumferential surface of the tool roller and extrude it from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0150] (5) Preparation of thermally conductive materials:

[0151] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0152] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0153]

Example 8

[0154] (1) Preparation of antioxidant layer 1:

[0155] ① Weigh out 3 parts by weight of chromium-manganese alloy, 3 parts by weight of nickel-magnesium alloy, and 3 parts by weight of Fe-Mn-Si based alloy. Mix them, pack them into a crucible, cover it, and place it in an atmosphere furnace. Perform pyrolysis treatment by vacuuming and circulating water. After cooling to room temperature, remove the mixture. During the pyrolysis process, first raise the temperature to 200℃ at 10℃ / min and hold for 1.5h to ensure uniform heating of the raw materials. Set the carbonization temperature to 700℃, the heating rate to 5℃ / min, and hold for 3h. Grind the mixture into powder. Prepare an aluminum chloride solution (concentration 2.0mol / L) and add it to the powder. Ultrasonically vibrate the mixture, then let it stand for 6h followed by 30min. Filter the mixture, wash with distilled water until no chloride ions are precipitated, and dry in a drying oven at 100℃ for 3h. After drying, obtain aluminum-modified alloy powder. Press this powder into an aluminum-modified transition alloy layer with a thickness of 35μm in a mold blank.

[0156] ② Weigh out 3 parts by weight of zirconium oxide ceramic, 3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder;

[0157] ③ Micro-arc oxidation is performed on the surface of the aluminum-modified transition alloy layer. The micro-arc-oxidized aluminum-modified transition alloy layer is placed on a heating platform, the resistance heating power supply is turned on, and the heating rod begins to heat the micro-arc-oxidized aluminum-modified transition alloy layer to the melting point of ultra-high temperature ceramics and maintains this temperature. The composition of the micro-arc oxidation electrolyte is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The temperature of the electrolyte is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply, with a positive voltage of 400V, a negative voltage of 800V, a positive empty ratio of 50%, a negative empty ratio of 50%, and a positive current density of 2A / cm². 2 Negative current density 1 A / cm 2 Voltage frequency 400Hz, oxidation time 30min;

[0158] ④ Place the mixed ceramic powder obtained in step ② onto the heated micro-arc oxidized aluminum-modified transition alloy layer. Turn on the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder and the aluminum-modified transition alloy layer, ensuring a pressure of 0.4 MPa at the contact surface. This ensures a tight bond between the mixed ceramic powder and the aluminum-modified transition alloy layer. After the ultrasonic head presses down for 3 seconds, thermoplastic deformation occurs at the contact surface. Maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply (1500W, 20kHz, duration 1.5s).

[0159] ⑤ Turn off the ultrasonic power supply, turn off the heating power supply, turn off the cylinder pressurization device, lift the ultrasonic head and remove it from the heating table to obtain a nanostructured ceramic layer that is combined with the aluminum modified transition alloy layer. The thickness of the nanostructured ceramic layer is 95μm. Then, it is air-cooled at a cooling rate of 20℃ / s to room temperature to ensure complete solidification at the interface.

[0160] (2) Preparation of carbon / carbon composite thermal conductive layer 2:

[0161] Weigh 50 parts of liquid crystal material and 3 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 90 parts of thermally conductive carbon fiber three-dimensional braided structure according to weight and impregnate it with mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain carbon / carbon composite thermally conductive layer 2.

[0162] (3) Preparation of composite graphene thermal conductive layer 4:

[0163] Weigh out 10 parts by weight of Cu3N surface-modified copper foil strips, 30 parts of epoxy resin doped with AlN and BN particles, 30 parts of graphene film, and coal tar powder. Layer these materials alternately in a stainless steel mold of appropriate size, following the sequence: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. After covering the mold with a cover plate, place the mold on a hot press and heat to 200℃, pressurize to 5MPa, and hot-press to form a composite. After holding the heat and pressure for 0.5 hours, allow it to cool naturally to obtain a preform. Carbonize the preform without removing it from the mold at 1000℃. After cooling, remove it and repeatedly spread coal tar powder in the stainless steel mold. Repeat the hot pressing and carbonization process 5 times to obtain a low-density carbon / carbon composite material with a thickness of 2mm. Next, using acetylene as the carbon source, low-density carbon / carbon composites were deposited with infiltration pyrolysis carbon via chemical vapor deposition at 1100℃ to achieve densification and reinforcement. The deposition time was 400 h, resulting in medium-density carbon / carbon composites. Then, the medium-density carbon / carbon composites were repeatedly impregnated with molten coal-based mesophase pitch with a residual carbon content of 65% under 5 MPa pressure seven times, followed by carbonization (1200℃) to obtain high-density carbon / carbon composites. Finally, the high-density carbon / carbon composites were graphitized at 2800℃ under inert gas conditions for 2 h, and after natural cooling, a two-dimensional high thermal conductivity carbon / carbon composite (2 mm) was obtained. The resulting two-dimensional high thermal conductivity carbon-carbon composite... The material and graphene film were molded together. The cavity in the mold was filled with asphalt and carbon powder. After pre-pressing by 10 MPa, it was placed in the sintering furnace cavity. The sintering program was set and sintering was carried out. The preparation of the layered composite material was completed under vacuum conditions. During sintering: the sample was heated from room temperature to 600℃ at a heating rate of 100℃ / min and held for 5 min. Then it was heated to 900℃ at a heating rate of 100℃ / min and held for 5 min. Then it began to cool down. During the heating stage from 600℃ to 900℃, the pressure was increased from 50 MPa to 100 MPa. During the cooling stage, before 500℃, the cooling rate was maintained at 10℃ / min by controlling the current. Then it was cooled with the furnace to obtain the composite graphene thermal conductive layer 4.

[0164] (4) Prepare inorganic thermal insulation foam layer 5:

[0165] Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. The SiHfBCN / C composite foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic thermal insulation foam layer 5.

[0166] (5) Preparation of thermally conductive materials:

[0167] The antioxidant layer 1 obtained in step (1), the carbon / carbon composite thermal conductive layer 2 obtained in step (2), the oscillating heat pipe layer 3, the composite graphene thermal conductive layer 4 obtained in step (3), and the inorganic thermal insulation foam layer 5 prepared in step (4) are sequentially bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. During bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, then an appropriate amount of thermal conductive grease is placed on a mesh plate, and the thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is then removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. Thermal conductive tape is then attached around each layer of thermal conductive grease to bond the layers together.

[0168] The device prepared in this embodiment includes an antioxidant layer 1, a carbon / carbon composite thermal conductive layer 2, an oscillating heat pipe layer 3, a composite graphene thermal conductive layer 4, and an inorganic thermal insulation foam layer 5 arranged from the outside to the inside.

[0169] [Testing]

[0170] The thermal conductivity of the heat-conducting devices prepared in Examples 2-8 above was measured using a Lindsay thermal conductivity meter, its bending strength was measured using a mechanical testing instrument, and its density was measured using an Inspire density meter. The obtained data are shown in Table 1.

[0171] Examples Thermal conductivity Bending strength Density Bending temperature Heat conduction 2 717 W / (m K) 217 MPa 1.9 g / cm 3 ]] 980℃ 370 W / m 2 ]] 3 736 W / (m K) 200 MPa 2.1 g / cm 3 ]]> 910℃ 460 W / m 2 ]] 4 739 W / (m K) 195 MPa 2.15 g / cm 3 ]]> 900℃ 490 W / m 2 ]] 5 758 W / (m K) 250 MPa 2.21 g / cm 3 ]]> 860℃ 510 W / m 2 ]] 6 766 W / (m K) 220 MPa 2.1 g / cm 3 ]]> 720℃ 550 W / m 2 ]] 7 823 W / (m K) 200 MPa 2.3 g / cm 3 ]]> 520℃ 560 W / m 2 ]]> 8 891 W / (m K) 171 MPa 2.48 g / cm 3 ]]> 450℃ 600 W / m 2 ]]

[0172] As shown in Table 1, the thermal conductivity and density of Examples 2-8 increase with the increase of graphene film content in the composite graphene thermal conductive layer 4, while the bending strength decreases with the decrease of graphene film content in the composite graphene thermal conductive layer 4. A thermal conductive device with a similar shape to the thermal conductive device provided by this invention but without the composite graphene thermal conductive layer 4 was tested; its bending point 6 temperature was 2300℃, while the average bending point 6 temperature of Examples 2-8 was 763℃. In comparison, the thermal conductive device provided by this invention has higher heat dissipation efficiency. Figure 2 As shown, the temperatures at which 5% heat loss begins in Examples 1 to 6 are 1026℃, 1034℃, 1009℃, 1032℃, 1081℃, and 1071℃, respectively. The 5% heat loss temperature in all examples exceeds 1000℃. Therefore, the heat dissipation device provided by the present invention has strong heat resistance and can be used in the electronic bay of an aircraft to dissipate heat and cool down the equipment inside the bay, thereby maintaining the normal operation of the equipment.

Claims

1. A heat dissipation device for an aircraft, characterized in that, The structure includes, from the outside in, an antioxidant layer (1), a carbon / carbon composite thermal conductive layer (2), an oscillating heat pipe layer (3), a composite graphene thermal conductive layer (4), and an inorganic thermal insulation foam layer (5), wherein: The antioxidant layer (1) includes an aluminum-modified transition alloy layer and a nanostructured ceramic layer disposed on the surface of the aluminum-modified transition alloy layer. The aluminum-modified transition alloy layer is composed of the following raw materials in parts by weight: 1-3 parts of chromium-manganese alloy, 1-3 parts of nickel-magnesium alloy, and 1-3 parts of Fe-Mn-Si based alloy. The nanostructured ceramic layer is composed of the following raw materials in parts by weight: 1-3 parts of zirconium oxide ceramic, 1-3 parts of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1-3 parts of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2. The composite graphene thermal conductive layer (4) is composed of the following raw materials in parts by weight: 10-30 parts copper foil strip, 10-30 parts thermal conductive adhesive, and 10-30 parts graphene film. The inorganic thermal insulation foam layer (5) is made of foam material.

2. The heat dissipation device for an aircraft according to claim 1, characterized in that, The thickness of the aluminum-modified transition alloy layer is 30–35 μm, and the thickness of the nanostructured ceramic layer is 90–95 μm.

3. The heat dissipation device for an aircraft according to claim 1, characterized in that, The carbon / carbon composite material is composed of the following raw materials in parts by weight: 60-90 parts of thermally conductive carbon fiber three-dimensional braided structure, 50-80 parts of liquid crystal material, and 1-5 parts of graphene nanosheets.

4. The heat dissipation device for an aircraft according to claim 1, characterized in that, The copper foil strip is surface modified with Cu3N; The thermally conductive adhesive is any one of graphene-reinforced thermally conductive silicone, copper foam-reinforced thermally conductive silicone, or epoxy resin doped with AlN and BN particles.

5. A heat dissipation device for an aircraft according to claim 1, characterized in that, The foam material is any one of SiBCN foam material, SiHfBCN foam material, SiBCN / C composite foam material, and SiHfBCN / C composite foam material.

6. A heat dissipation device for an aircraft according to claim 1, characterized in that, The antioxidant layer (1), carbon / carbon composite thermal conductive layer (2), oscillating heat pipe layer (3), composite graphene thermal conductive layer (4) and inorganic thermal insulation foam layer (5) are all bent strip structures with pointed ends.

7. A method for preparing a heat conduction device for an aircraft as described in any one of claims 1 to 6, characterized in that, Includes the following steps: Step 1. Prepare the antioxidant layer: Step 1.

1. Weigh 1-3 parts by weight of chromium-manganese alloy, 1-3 parts by weight of nickel-magnesium alloy, and 1-3 parts by weight of Fe-Mn-Si based alloy. Mix them and pack them into a reaction vessel, compact and cover it. Place it in an atmosphere furnace, evacuate, turn on the water pump, and pyrolyze at 150-200℃ for 0.5-1.5h. After cooling to room temperature, take it out and carbonize it at 500-700℃ for 2-3h. Grind it into powder, add aluminum chloride solution with a concentration of 0.5-2.0mol / L, ultrasonically vibrate and let it stand. Filter and wash until no chloride ions are precipitated. Dry it at 70-100℃ for 1-3h. After drying, aluminum modified alloy powder is obtained. Press it into an aluminum modified transition alloy layer with a thickness of 30-35μm in a mold blank. Step 1.

2. Weigh out 1-3 parts by weight of zirconium oxide ceramic, 1-3 parts by weight of ZrO2 ceramic material modified by Y2O3 and La2O3, and 1-3 parts by weight of ZrB2-20SiC ultra-high temperature ceramic modified by MoSi2 and TaSi2 to obtain mixed ceramic powder B. Step 1.

3. Micro-arc oxidation is performed on the surface of the aluminum modified transition alloy layer. The electrolyte composition for micro-arc oxidation is: 6 g / L Na2SiO3·9H2O, 1.8 g / L KOH, and 1 g / L NaF. The electrolyte temperature is controlled at 25℃ during the oxidation process. The power supply parameters are a bidirectional pulse power supply with a positive voltage of 0–400V, a negative voltage of 0–800V, a positive open area ratio of 50%, a negative open area ratio of 50%, and a positive current density of 2 A / cm². 2 Negative current density 1 A / cm 2 The voltage frequency was 400 Hz, the oxidation time was 30 min, the temperature of the aluminum modified transition alloy layer after micro-arc oxidation was heated to the melting point of ultra-high temperature ceramics and maintained at this temperature, and the mixed ceramic powder B obtained in step 1.2 was placed on its surface. Step 1.

4. Open the cylinder pressurization device to drive the ultrasonic head to press the mixed ceramic powder B and the aluminum modified transition alloy layer to make them fit tightly. After the ultrasonic head presses for 3 seconds, maintain the pressure of the ultrasonic head, turn on the ultrasonic power supply, the ultrasonic power is 1500W, the ultrasonic frequency is 20kHz, and the duration is 1.5s. Step 1.

5. Obtain a nanostructured ceramic layer bonded to the aluminum-modified transition alloy layer. The thickness of the nanostructured ceramic layer is 90-95 μm. Air-cooled until the interface is completely solidified. Step 2. Prepare a carbon / carbon composite thermally conductive layer: Weigh 50-80 parts of liquid crystal material and 1-5 parts of graphene nanosheets according to weight to prepare mixed solution A. Weigh 60-90 parts of thermally conductive carbon fiber three-dimensional woven structure according to weight to impregnate mixed solution A. Cure at 3 MPa and 1000℃ for 3 hours to obtain a carbon / carbon composite thermally conductive layer. Step 3. Prepare the composite graphene thermally conductive layer: Step 3.

1. Weigh out 10-30 parts by weight of copper foil strips, 10-30 parts of thermally conductive adhesive, 10-30 parts of graphene film, and coal tar powder. Layer these components alternately in a mold in the following order: coal tar powder - copper foil strips - coal tar powder - graphene film - thermally conductive adhesive - coal tar powder. Place the mold on a hot press at 200℃ and 5MPa to form a composite. After holding the temperature and pressure for 0.5 hours, allow it to cool naturally to obtain a preform. Carbonize the preform (without removing it from the mold) at 1000℃. After cooling, remove it and repeatedly sprinkle coal tar powder into a stainless steel mold. Low-density carbon / carbon composite material was obtained by hot pressing and carbonization five times. Using acetylene as the carbon source, the low-density carbon / carbon composite material was deposited at 1100℃ for 400h to obtain medium-density carbon / carbon composite material. The medium-density carbon / carbon composite material was impregnated with molten coal-based mesophase pitch with a residual carbon rate of 65% under a pressure of 5MPa and carbonized at 1200℃. This process was repeated seven times to obtain high-density carbon / carbon composite material. The high-density carbon / carbon composite material was graphitized at 2800℃ in an inert gas for 2h and then naturally cooled to obtain a bidirectional high thermal conductivity carbon / carbon composite material. Step 3.

2. The bidirectional high thermal conductivity carbon-carbon composite material obtained in step 3.1 is molded with graphene film. The cavity in the mold is filled with asphalt and carbon powder. Under vacuum conditions, it is pre-pressed at 10 MPa and then placed in a sintering furnace. It is sintered at 50 MPa and 600℃ for 5 min, and then sintered at 900℃ and 100 MPa for 5 min. After cooling, a composite graphene thermal conductive layer is obtained. Step 4: Prepare the inorganic thermal insulation foam layer: Prepare a rotating tool roller and an extrusion die with a die lip. A gap is formed between the tool roller and the extrusion die. Foam material is introduced onto the main circumferential surface of the tool roller and extruded from the extrusion die to obtain the desired inorganic heat insulation foam layer. Step 5: Preparation of thermally conductive materials: The antioxidant layer obtained in step (1), the carbon / carbon composite thermal conductive layer obtained in step (2), the oscillating heat pipe layer, the composite graphene thermal conductive layer obtained in step (3), and the inorganic thermal insulation foam layer prepared in step (4) are bonded together with thermal conductive tape and thermal conductive grease to obtain a heat conduction device. When bonding, the thermal conductive grease is first stirred at room temperature for 12 hours, and then an appropriate amount of thermal conductive grease is placed on the mesh plate. The thermal conductive grease is evenly filled into the mesh of the mesh plate using a scraper. The mesh plate is removed, and the thermal conductive grease is evenly applied to the gaps between the layers of the heat conduction device. The thermal conductive tape is attached around each layer of thermal conductive grease to bond the layers together.

8. The method for preparing a heat conduction device for an aircraft according to claim 7, characterized in that, In step 1.1, the heating rate during pyrolysis is 10℃ / min, the heating rate during carbonization is 5℃ / min, the ultrasonic vibration time is 3-6h, and the settling time is 30min.

9. The method for preparing a heat conduction device for an aircraft according to claim 7, characterized in that, In step 1.5, the air cooling rate is 20℃ / s.

10. The method for preparing a heat conduction device for an aircraft according to claim 7, characterized in that, In step 3.2, the heating rate during both sintering processes is 100℃ / min, and the cooling rate between 900℃ and 500℃ is 10℃ / min. The furnace is cooled from 500℃ to room temperature.

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