Radiation and convection dual-function heat dissipation coating and preparation method thereof

Abstract

The invention relates to the technical field of electrical auxiliary materials, and particularly discloses a radiation and convection dual-function heat dissipation coating and a preparation method thereof. The radiation and convection dual-function heat dissipation coating comprises a graphene infrared radiation layer and a downstream convection heat dissipation material distributed on the graphene infrared radiation layer, and the graphene infrared radiation layer is prepared from the following raw materials in parts by weight: 35-45 parts of elemental carbon powder; 10-14 parts of alumina powder; 4-6 parts of a water-based adhesive; 30-40 parts of a water-based solvent; 6-10 parts of a filler; 1-3 parts of an antioxidant; the airflow convection heat dissipation material comprises flaky alloy heat dissipation particles, the flaky alloy heat dissipation particles are copper-iron alloy containing copper and iron, the copper content of the copper-iron alloy is 85-95%, and the balance is iron. According to the radiation and convection dual-function heat dissipation coating, the radiation and convection dual heat dissipation effect is achieved, and the heat dissipation effect is greatly improved for equipment with low surface temperature such as a transformer and a motor.

Description

Technical Field

[0001] The present application relates to the technical field of electrical auxiliary materials, and more specifically, to a radiation-convection dual-function heat dissipation coating and a preparation method thereof. Background Art

[0002] There are three ways of heat conduction: convection, conduction and radiation; convection heat transfer refers to the heat transfer process caused by the relative displacement of particles in the fluid; heat conduction is the heat transfer phenomenon when there is no macroscopic movement in the medium, which can occur in solids, liquids and gases; radiation heat refers to the heat transferred by an object through thermal radiation.

[0003] Among them, radiation heat transfer is a highly efficient non-contact heat transfer process. The infrared radiation coating of the existing technology utilizes the special physical properties of nano-graphite. When coated on the surface of the heating element, it can increase the infrared emissivity of the heating element, strengthen the radiation heat transfer process, and increase the heat conduction per unit time, that is, improve the infrared radiation heat transfer capacity. For electrical equipment such as motors and transformers that are prone to heat, surface coating can increase the heat dissipation effect, reduce the energy consumption of conductive materials, improve work efficiency, and extend equipment life.

[0004] With respect to the above-mentioned related technologies, the inventors believe that for devices such as transformers and motors whose surface temperatures are not high, the low external temperature will cause heat to dissipate faster, increasing the difficulty of heat dissipation. It is difficult to achieve the expected heat dissipation effect by relying solely on radiation heat dissipation. Therefore, it is urgent to propose a solution to solve the above-mentioned technical problems. Summary of the invention

[0005] In order to improve the heat dissipation effect of the coating in low-temperature environments, the present application provides a radiation-convection dual-function heat dissipation coating and a preparation method thereof.

[0006] In a first aspect, the present application provides a radiation-convection dual-function heat dissipation coating, which adopts the following technical solution:

[0007] A radiation-convection dual-function heat dissipation coating comprises a graphene infrared radiation layer and a heat dissipation material disposed thereon for convection along the airflow. The graphene infrared radiation layer is made of the following raw materials in parts by weight:

[0008] 35-45 parts of single carbon powder;

[0009] 10-14 parts of alumina powder;

[0010] 4-6 parts of water-based adhesive;

[0011] 30-40 parts of aqueous solvent;

[0012] 6-10 parts of filler;

[0013] 1-3 parts of antioxidants;

[0014] The heat dissipation material along the airflow convection includes flaky alloy heat dissipation particles, which are copper-iron alloys containing copper and iron, wherein the copper content of the copper-iron alloy is 85-95% and the rest is iron.

[0015] By adopting the above technical scheme, the graphene infrared radiation layer mainly utilizes the high thermal conductivity and high emissivity characteristics of graphene. After being coated on the surface of an object, it can transfer heat to the coating and transfer it to the outside with high radiation heat dissipation capacity, thereby achieving efficient heat transfer or cooling effect; the airflow convection heat dissipation material includes flaky alloy heat dissipation particles, which are copper-iron alloys containing copper and iron, and have excellent heat dissipation performance; at the same time, the distribution of the airflow convection heat dissipation material on the graphene infrared radiation layer is equivalent to forming a large number of micro heat sinks on the surface of the radiation convection dual-function heat dissipation coating, which multiplies the heat dissipation effect of the coating and realizes the dual heat dissipation effect of radiation and convection. For equipment such as transformers and motors with low surface temperature, the heat dissipation effect is even better.

[0016] Preferably, the flaky alloy heat dissipation particles have a thickness of 10-30 nm, and a length and width of 0.3-0.5 mm.

[0017] Preferably, the water-based adhesive is any one of polyvinyl alcohol, vinyl acetate, acrylic, polyurethane and silicone.

[0018] Preferably, the aqueous solvent is one or a combination of water, ethanol, glycerol, polyethylene glycol, propylene glycol methyl ether, dipropylene glycol butyl ether and propylene carbonate.

[0019] Preferably, the filler is one or a combination of calcium carbonate, barite powder, talc powder, kaolin, mica powder, wollastonite, bentonite and quartz powder.

[0020] Preferably, it also includes an anti-oxidation nano protective layer placed on the graphene infrared radiation layer and the heat dissipation material along the airflow convection, and the anti-oxidation nano protective layer is made of the following raw materials in parts by weight:

[0021] 1-2 parts of titanium dioxide particles;

[0022] 10-20 parts of inorganic solvent.

[0023] By adopting the above technical scheme, the anti-oxidation nano-protective layer is like a precision woven web in the microscopic world. It not only has extraordinary high-temperature stability and can maintain structural integrity and stable performance in extreme environments, but also has excellent anti-oxidation properties. It can effectively resist the penetration of corrosive media such as oxygen and water vapor, delay the aging process of the material, and significantly improve the durability and service life of the material. As a result, the graphene infrared radiation layer and the airflow convection heat dissipation material can play a stable and excellent cooperative effect with each other during the application process, thereby bringing about excellent heat dissipation effect.

[0024] Preferably, the raw material of the graphene infrared radiation layer further comprises 2-6 parts by weight of a functional additive, the functional additive is composed of boron nitride nanosheets and carbon nanotubes, and the weight ratio of the boron nitride nanosheets to the carbon nanotubes is 1:(0.8-1.2);

[0025] The downstream convection heat dissipation material is modified before use, and the modification steps are as follows:

[0026] After the heat dissipation material along the air flow convection is treated with acid to remove the oxide scale, it is placed in the modification liquid at 40-60°C and immersed for 3-10 minutes, and then taken out, washed and dried to complete the modification treatment;

[0027] The modified liquid is an aqueous solution of zinc dihydrogen sulfate, nickel hydroxide and sodium nitrite, wherein the content of zinc dihydrogen sulfate is 2-3 g / L, the content of nickel hydroxide is 0.12-0.16 g / L, and the content of sodium nitrite is 0.16-0.24 g / L.

[0028] By adopting the above technical scheme, functional additives containing boron nitride nanosheets and carbon nanotubes are used in the graphene infrared radiation layer. Through the cooperation between the boron nitride nanosheets and the carbon nanotubes, a multi-level three-dimensional thermal conductive network can be formed, which can not only improve the heat conduction and heat dissipation capabilities, but also play a structural embedding and fixing role for the downstream convection heat dissipation material; the downstream convection heat dissipation material is modified to form a porous membrane structure on the surface of the downstream convection heat dissipation material, which can improve the wettability of the graphene infrared radiation layer to the surface of the downstream convection heat dissipation material, improve the interface bonding, and strengthen the mechanical riveting effect between the two, thereby ensuring the stability of heat transfer; at the same time, when the graphene infrared radiation layer and the modified downstream convection heat dissipation material are combined, the boron nitride nanosheets and carbon nanotubes can utilize the porous membrane structure on the surface of the downstream convection heat dissipation material to form a penetrating and combining structure, so that heat transfer can be carried out stably and efficiently, thereby further improving the heat dissipation effect of the radiation convection dual-function heat dissipation coating.

[0029] Preferably, the boron nitride nanosheets have a thickness of 100-200 nm and a thickness of 1-2 μm; the carbon nanotubes have a diameter of 10-30 nm and a length of 3-10 μm.

[0030] By adopting the above technical scheme, when the boron nitride nanosheets and carbon nanotubes of the above specifications are used in combination, the thermal conductive network enhancement effect formed is more significant, and can form a better combination and coordination effect with the porous membrane structure on the surface of the upstream convection heat dissipation material, thereby enabling the graphene infrared radiation layer and the downstream convection heat dissipation material to form a better coordination and exert a more significant corresponding effect, thereby obtaining a radiation-convection dual-function heat dissipation coating with better application quality.

[0031] In a second aspect, the present application provides a method for preparing a radiation-convection dual-function heat dissipation coating, which adopts the following technical solution:

[0032] A method for preparing a radiation-convection dual-function heat dissipation coating comprises the following steps:

[0033] (1) preparing raw materials including simple carbon powder, aluminum oxide powder, water-based binder, water-based solvent, filler and antioxidant according to a proportion;

[0034] (2) The raw materials in step (1) are mixed evenly to obtain a graphene infrared radiation layer mixture, which is sprayed on the desired object base surface, and then a heat dissipation material is sprayed along the airflow convection. The surface is then exceptionally stretched using a modified magnet, and then pulled back and forth along the airflow direction. Finally, it is dried and formed to obtain a radiation convection dual-function heat dissipation coating.

[0035] By adopting the above technical scheme, in the above operation, after the heat dissipation material along the airflow convection is adhered to the surface of the graphene infrared radiation layer, because the heat dissipation material along the airflow convection contains ferromagnetism, the modified magnet is used to perform exceptional stretching on the surface, so that the iron surface stands up, and then the modified magnet is pulled back and forth along the direction of airflow flow, such as along the direction of the heat dissipation ribs on the surface of equipment with low surface temperature such as transformers and motors, so that the flaky heat dissipation particles can be changed to a vertical state along the direction of airflow, thereby achieving a dual heat dissipation effect of radiation and convection, which doubles the heat dissipation effect of the coating.

[0036] Preferably, the modified magnet is made of neodymium iron boron magnet, and its magnetic induction intensity is ≥0.8T at 0.1 meter, and the side of the modified magnet facing the coated base surface of the object is a horizontal structure.

[0037] In summary, this application has the following beneficial effects:

[0038] 1. The present application realizes the dual heat dissipation effect of radiation and convection, and has a better heat dissipation effect for electrical equipment. The existing technology has a small heat dissipation optimization range for equipment with low surface temperature such as transformers and motors, and generally can only reduce the surface temperature rise by a few degrees. The present invention increases the convection radiation enhancement effect along the airflow direction, so that the heat dissipation effect of the coating is doubled, especially in low temperature occasions below 80°C. The existing technology can only reduce about 5 degrees, and the present invention can reduce more than 12 degrees, greatly improving the heat dissipation effect;

[0039] 2. The present application uses functional additives composed of boron nitride nanosheets and carbon nanotubes in the graphene infrared radiation layer, and modifies the co-flow convection heat dissipation material before use. This makes the interface between the modified co-flow convection heat dissipation material and the graphene infrared radiation layer more stable, and the heat transfer can be more stable and efficient, which can further improve the heat dissipation effect of the radiation-convection dual-function heat dissipation coating, and thus obtain a radiation-convection dual-function heat dissipation coating with better application quality. DETAILED DESCRIPTION

[0040] The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0041] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present application are commercially available.

[0042] Example

[0043] Example 1

[0044] A radiation-convection dual-function heat dissipation coating comprises a graphene infrared radiation layer and a heat dissipation material disposed thereon for convection along the airflow. The raw materials used to prepare the graphene infrared radiation layer and their corresponding weights are shown in Table 1, and the coating is prepared by the following steps:

[0045] (1) preparing raw materials including simple carbon powder, aluminum oxide powder, water-based binder, water-based solvent, filler and antioxidant according to a proportion;

[0046] (2) The raw materials in step (1) are mixed evenly to obtain a graphene infrared radiation layer mixture, which is sprayed on the desired object base surface, and then a powder spray pot is used to spray the heat dissipation material along the airflow convection. The nozzle of the powder spray pot has a spray angle of 30° and a spray amount of 0.2 g / s. Then, the surface is stretched exceptionally by using a modified magnet, and then it is pulled back and forth along the airflow direction. Finally, it is dried and shaped to obtain a radiation convection dual-function heat dissipation coating.

[0047] Note: In the above operation, the heat dissipation material for convection along the airflow is flaky alloy heat dissipation particles, which are copper-iron alloys containing copper and iron, wherein the copper content of the copper-iron alloy is 90% and the rest is iron; the thickness of the flaky alloy heat dissipation particles is 20nm, and the length and width are 0.4mm. The single carbon powder is graphene with a particle size of 10000 mesh; the particle size of the alumina powder is 200 mesh; the water-based binder is polyvinyl alcohol; the water-based solvent is composed of water and polyethylene glycol in a weight ratio of 7:3; the filler is calcium carbonate; and the antioxidant is 2,6-di-tert-butyl-4-methylphenol.

[0048] Example 2-3

[0049] A radiation-convection dual-function heat dissipation coating, which is different from Example 1 in that the raw materials used to prepare the graphene infrared radiation layer and their corresponding weights are shown in Table 1.

[0050] Table 1 Raw materials used in preparing the graphene infrared radiation layer in Examples 1-3 and their weight portions (kg / portion)

[0051] raw material Example 1 Example 2 Example 3 Single-element toner 40 35 45 Alumina powder 12 10 14 Water-based adhesive 5 4 6 Aqueous solvent 35 30 40 filler 8 6 10 Antioxidants 2 1 3

[0052] Example 4

[0053] A radiation-convection dual-function heat dissipation coating is different from Example 1 in that the heat dissipation material for convection along the airflow is flaky alloy heat dissipation particles, and the flaky alloy heat dissipation particles are copper-iron alloy containing copper and iron, wherein the copper content of the copper-iron alloy is 85% and the rest is iron.

[0054] Example 5

[0055] A radiation-convection dual-function heat dissipation coating is different from Example 1 in that the heat dissipation material for convection along the airflow is flaky alloy heat dissipation particles, and the flaky alloy heat dissipation particles are copper-iron alloy containing copper and iron, wherein the copper content of the copper-iron alloy is 95% and the rest is iron.

[0056] Example 6

[0057] A radiation-convection dual-function heat dissipation coating is different from Example 1 in that the thickness of the flaky alloy heat dissipation particles is 10-nm, and the length and width are 0.5 mm.

[0058] Example 7

[0059] A radiation-convection dual-function heat dissipation coating is different from Example 1 in that the thickness of the flaky alloy heat dissipation particles is 30 nm, and the length and width are 0.3 mm.

[0060] Example 8

[0061] A radiation-convection dual-function heat dissipation coating, which differs from Example 1 in that it also includes an anti-oxidation nano-protective layer placed on the graphene infrared radiation layer and the memory alloy dynamic convection heat dissipation material, and the anti-oxidation nano-protective layer is formed by mixing the following raw materials in parts by weight and then spraying and drying: 1.5 parts of titanium dioxide particles; 15 parts of inorganic solvent; titanium dioxide particles larger than 500,000 mesh, and 600,000 mesh is selected in this embodiment.

[0062] Example 9

[0063] A radiation-convection dual-function heat dissipation coating, which is different from Example 8 in that the anti-oxidation nano protective layer is formed by mixing the following raw materials in parts by weight and then spraying and drying: 1 part of titanium dioxide particles; 20 parts of inorganic solvents.

[0064] Example 10

[0065] A radiation-convection dual-function heat dissipation coating, which is different from Example 8 in that the anti-oxidation nano protective layer is formed by mixing the following raw materials in parts by weight and then spraying and drying: 2 parts of titanium dioxide particles; 10 parts of inorganic solvent.

[0066] Embodiment 11

[0067] A radiation-convection dual-function heat dissipation coating, which is different from Example 1 in that 4 parts by weight of a functional additive are also added to the raw material of the graphene infrared radiation layer, and the functional additive is composed of boron nitride nanosheets and carbon nanotubes in a weight ratio of 1:1; the thickness of the boron nitride nanosheets is 150nm and the thickness is 1.5μm; the diameter of the carbon nanotubes is 20nm and the length is 6.5μm.

[0068] The heat dissipation material along the airflow convection is modified before use, and the modification steps are as follows:

[0069] After the heat dissipation material along the air flow convection is treated with acid to remove the oxide scale, it is immersed in the modification liquid at 50°C for 6.5 minutes, and then taken out, washed and dried to complete the modification treatment;

[0070] The modified liquid is an aqueous solution of zinc dihydrogen sulfate, nickel hydroxide and sodium nitrite, wherein the content of zinc dihydrogen sulfate is 2.5 g / L, the content of nickel hydroxide is 0.14 g / L, and the content of sodium nitrite is 0.2 g / L.

[0071] Example 12

[0072] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the weight portion of the functional additive added is 2 parts.

[0073] Example 13

[0074] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the weight portion of the functional additive added is 6 parts.

[0075] Embodiment 14

[0076] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the functional additive is composed of boron nitride nanosheets and carbon nanotubes in a weight ratio of 1:0.8.

[0077] Embodiment 15

[0078] A radiation-convection dual-function heat dissipation coating, which differs from Example 11 in that the functional additive is composed of boron nitride nanosheets and carbon nanotubes in a weight ratio of 1:1.2.

[0079] Example 16

[0080] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the thickness of the boron nitride nanosheet is 100nm and the thickness is 2μm; the diameter of the carbon nanotube is 10nm and the length is 10μm.

[0081] Embodiment 17

[0082] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the thickness of the boron nitride nanosheet is 200nm and the thickness is 1μm; the diameter of the carbon nanotube is 30nm and the length is 3μm.

[0083] Embodiment 18

[0084] A radiation-convection dual-functional heat dissipation coating, which is different from Example 11 in that boron nitride nanosheets are not used in the functional additive.

[0085] Embodiment 19

[0086] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that carbon nanotubes are not used in the functional additive.

[0087] Embodiment 20

[0088] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the heat dissipation material for convection along the airflow is modified before use, and the modification steps are as follows:

[0089] After the heat dissipation material along the air flow convection is treated with acid to remove the oxide scale, it is immersed in the modification liquid at 40°C for 10 minutes, and then taken out, washed and dried to complete the modification treatment;

[0090] The modified liquid is an aqueous solution of zinc dihydrogen sulfate, nickel hydroxide and sodium nitrite, wherein the content of zinc dihydrogen sulfate is 2 g / L, the content of nickel hydroxide is 0.12 g / L, and the content of sodium nitrite is 0.16 g / L.

[0091] Embodiment 21

[0092] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the heat dissipation material for convection along the airflow is modified before use, and the modification steps are as follows:

[0093] After the heat dissipation material along the air flow convection is treated with acid to remove the oxide scale, it is immersed in the modification liquid at 60°C for 3 minutes, and then taken out, washed and dried to complete the modification treatment;

[0094] The modified liquid is an aqueous solution of zinc dihydrogen sulfate, nickel hydroxide and sodium nitrite, wherein the content of zinc dihydrogen sulfate is 3 g / L, the content of nickel hydroxide is 0.16 g / L, and the content of sodium nitrite is 0.24 g / L.

[0095] Embodiment 22

[0096] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that the heat dissipation material for convection along the airflow is not modified.

[0097] Embodiment 23

[0098] A radiation-convection dual-function heat dissipation coating, which is different from Example 11 in that no functional additive is used in the raw materials of the graphene infrared radiation layer.

[0099] Comparative Example

[0100] Comparative Example 1

[0101] A heat dissipation coating is different from the first embodiment in that no heat dissipation material along the airflow convection is used.

[0102] Performance testing

[0103] Test samples: The radiation-convection dual-function heat dissipation coatings obtained in Examples 1-23 were used as test samples 1-23, and the heat dissipation coating obtained in Comparative Example 1 was used as control sample 1.

[0104] Test method: A 48V-1.5KW-1500 rpm DC traction permanent magnet brushless motor is selected as the test motor. After scraping off the surface coating, the motor is operated normally for 10 hours. The temperature sensor installed inside the motor is used to measure the internal temperature of the motor at this time, and the motor is maintained at a low temperature below 80°C throughout the test. In the same way, after scraping off the surface coating, the heat dissipation coating in the test samples 1-23 and the control sample 1 is used respectively. After continuous operation at maximum power for 10 hours, the temperature sensor installed inside the motor is used to measure the internal temperature of the motor at this time, and the temperature reduction value after using the heat dissipation coating is calculated. The temperature reduction value = A0-A1. The greater the temperature reduction value, the higher the heat dissipation effect of the heat dissipation coating. The test results of the test samples 1-23 and the control sample 1 are recorded in Table 2.

[0105] Table 2 Test results of test samples 1-23 and control sample 1

[0106]

[0107]

[0108] Combining Examples 1-5 and Comparative Example 1 and Table 2, it can be seen that the convection heat dissipation material along the airflow is distributed on the graphene infrared radiation layer, and then many micro heat sinks are formed on the surface of the radiation-convection dual-function heat dissipation coating, which doubles the heat dissipation effect of the coating. For equipment such as transformers and motors with low surface temperatures, only the graphene infrared radiation layer is used in Comparative Example 1 to play a heat dissipation role, which can only reduce the temperature by about 5°C. However, the present application achieves the dual heat dissipation effect of radiation and convection on the basis of the graphene infrared radiation scheme. In low-temperature occasions below 80°C, the present invention can achieve a reduction effect of more than 12 degrees, and the heat dissipation effect is greatly improved.

[0109] Combining Example 1 and Example 6-7 with Table 2, it can be seen that the thickness of the flaky alloy heat dissipation particles is 10-30nm, and the length and width are 0.3-0.5mm, which can enable the heat dissipation material along the airflow convection and the graphene infrared radiation layer to exert an excellent and stable coordination effect, thereby bringing about excellent and stable heat dissipation performance.

[0110] It can be seen from Example 1 and Examples 8-10 and Table 2 that the use of the anti-oxidation nano-protective layer can, to a certain extent, improve the excellent heat dissipation effect of the combination of the graphene infrared radiation layer and the airflow convection heat dissipation material, thereby causing a certain increase in the temperature reduction value obtained in the above test.

[0111] It can be seen from Example 1 and Examples 11-15, Examples 20-21 and Table 2 that the present application can further improve the heat dissipation effect of the radiation-convection dual-functional heat dissipation coating by using functional additives composed of boron nitride nanosheets and carbon nanotubes in the graphene infrared radiation layer and modifying the airflow convection heat dissipation material before use, thereby significantly increasing the temperature reduction value obtained in the test.

[0112] Combined with Examples 16-17 and Table 2, it can be seen that the thickness of the boron nitride nanosheets is 100-200nm and the thickness is 1-2μm; the diameter of the carbon nanotubes is 10-30nm and the length is 3-10μm; it can enable the graphene infrared radiation layer and the airflow convection heat dissipation material to form a better coordination and exert a more significant corresponding effect, thereby obtaining a radiation convection dual-function heat dissipation coating with better application quality.

[0113] Combined with Examples 18-19 and Table 2, it can be seen that, among the functional additives, if only one of the boron nitride nanosheets and carbon nanotubes is used, although it can bring about an improvement in heat dissipation performance, the improvement effect is far less than the excellent effect brought by the combination of the two. It can be seen that the combined application of boron nitride nanosheets and carbon nanotubes in the graphene infrared radiation layer can bring a significant improvement effect on the interface bonding between the graphene infrared radiation layer and the convection heat dissipation material along the airflow, so that the heat conduction dissipation capacity is significantly improved.

[0114] Combined with Examples 22-23 and Table 2, it can be seen that the lack of functional additives in the graphene infrared radiation layer, or the failure to modify the convection heat dissipation material along the airflow, will lead to a significant reduction in the heat dissipation capacity of the radiation-convection dual-function heat dissipation coating. Judging from the performance of the temperature reduction value, the two have a synergistic effect and are indispensable, which can ensure that the heat dissipation effect of the radiation-convection dual-function heat dissipation coating is significantly improved.

[0115] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A radiation-convection dual-function heat dissipation coating, characterized in that: The invention comprises a graphene infrared radiation layer and a heat dissipation material arranged thereon and arranged along the airflow convection. The graphene infrared radiation layer is made of the following raw materials in parts by weight: 35-45 parts of single carbon powder; 10-14 parts of alumina powder; 4-6 parts of water-based adhesive; 30-40 parts of aqueous solvent; 6-10 parts of filler; 1-3 parts of antioxidants; The heat dissipation material along the airflow convection includes flaky alloy heat dissipation particles, which are copper-iron alloys containing copper and iron, wherein the copper content of the copper-iron alloy is 85-95% and the rest is iron.

2. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The flaky alloy heat dissipation particles have a thickness of 10-30 nm, and a length and a width of 0.3-0.5 mm.

3. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The water-based adhesive is any one of polyvinyl alcohol, vinyl acetate, acrylic, polyurethane and silicone.

4. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The aqueous solvent is one or a combination of water, ethanol, glycerol, polyethylene glycol, propylene glycol methyl ether, dipropylene glycol butyl ether and propylene carbonate.

5. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The filler is one or a combination of calcium carbonate, barite powder, talcum powder, kaolin, mica powder, wollastonite, bentonite and quartz powder.

6. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: It also includes an anti-oxidation nano protective layer placed on the graphene infrared radiation layer and the heat dissipation material along the airflow convection, and the anti-oxidation nano protective layer is made of the following raw materials in parts by weight: 1-2 parts of titanium dioxide particles; 10-20 parts of inorganic solvent.

7. The radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The raw material of the graphene infrared radiation layer is further added with 2-6 parts by weight of a functional additive, the functional additive is composed of boron nitride nanosheets and carbon nanotubes, and the weight ratio of the boron nitride nanosheets to the carbon nanotubes is 1:(0.8-1.2); The downstream convection heat dissipation material is modified before use, and the modification steps are as follows: After the heat dissipation material along the air flow convection is treated with acid to remove the oxide scale, it is placed in the modification liquid at 40-60°C and immersed for 3-10 minutes, and then taken out, washed and dried to complete the modification treatment; The modified liquid is an aqueous solution of zinc dihydrogen sulfate, nickel hydroxide and sodium nitrite, wherein the content of zinc dihydrogen sulfate is 2-3 g / L, the content of nickel hydroxide is 0.12-0.16 g / L, and the content of sodium nitrite is 0.16-0.24 g / L.

8. The radiation-convection dual-function heat dissipation coating according to claim 7, characterized in that: The boron nitride nanosheet has a thickness of 100-200 nm and a thickness of 1-2 μm; the carbon nanotube has a diameter of 10-30 nm and a length of 3-10 μm.

9. The method for preparing the radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The following steps are involved: (1) preparing raw materials including simple carbon powder, aluminum oxide powder, water-based binder, water-based solvent, filler and antioxidant according to a proportion; (2) The raw materials in step (1) are mixed evenly to obtain a graphene infrared radiation layer mixture, which is sprayed on the desired object base surface, and then a heat dissipation material is sprayed along the airflow convection. The surface is then exceptionally stretched using a modified magnet, and then pulled back and forth along the airflow direction. Finally, it is dried and formed to obtain a radiation convection dual-function heat dissipation coating.

10. The method for preparing the radiation-convection dual-function heat dissipation coating according to claim 1, characterized in that: The modified magnet is made of neodymium iron boron magnet, and its magnetic induction intensity is ≥0.8T at 0.1 meter, and the side of the modified magnet facing the coated base surface of the object is a horizontal structure.

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