High fluid impact buffering performance high flux heat exchange tube and preparation method thereof

Abstract

The application discloses a high-fluid-impact buffering performance high-throughput heat exchange tube and a preparation method thereof, and belongs to the technical field of heat exchange tube preparation. The heat exchange tube comprises a combination of brazing, sintering and ultrasonic surface rolling technology, especially an ultrasonic device containing a protective reinforcing liquid is used in the ultrasonic surface rolling process. Through control of ultrasonic amplitude and repeated processing, fine treatment is realized on the surface of the heat exchange tube, the surface roughness is significantly reduced, the friction coefficient is reduced, the toughness, wear resistance and corrosion resistance of the heat exchange tube, especially the bending part, are improved, the problems that the heat exchange tube is prone to intergranular corrosion and the base body strength is reduced due to fluid impact deformation in the prior art are effectively solved, and the heat exchange uniformity of the heat exchange tube is ensured.

Description

Technical Field

[0001] This invention belongs to the field of heat exchanger tube preparation technology, and more specifically, relates to a high-throughput heat exchanger tube with high fluid shock buffering performance and its preparation method. Background Technology

[0002] High-flux heat exchange tubes are key components of high-flux heat exchangers. Their surfaces feature a porous layer structure with high-density interconnected pores, which not only increases the heat exchange area but also significantly increases the number of vaporization nuclei, thereby greatly enhancing boiling heat transfer capacity. Currently, sintered high-flux heat exchange tubes are the main manufacturing method. By sintering a thin layer of porous, high-efficiency heat exchange tube with a specific structure onto the surface of a conventional heat exchange tube, they have become the shell-and-tube heat exchange element with the most significant enhancement of boiling heat transfer effect, and are widely used in engineering fields such as oil refining, petrochemicals, and chemicals.

[0003] However, existing sintered high-flux heat exchange tubes still have some problems: First, excessively high sintering temperatures can reduce the mechanical properties of the tubes, while lowering the sintering temperature can affect the quality of the porous layer; second, impurities are easily mixed in during the sintering process, introducing macroscopic defects; finally, the porous layer prepared by the traditional powder sintering method has an uneven pore size distribution, which is difficult to control, and due to intergranular corrosion, the strength and heat transfer performance of the matrix will decrease after corrosion.

[0004] Furthermore, heat exchange tubes typically require high-speed flow of heat exchange fluid to exchange heat with hot or cold loads. Since heat exchange tubes are usually designed as coils to save installation space, this inevitably leads to high-speed impact of the fluid on the bending areas of the tubes. In this case, the fluid buffering performance of the heat exchange tubes becomes particularly important. Moreover, the sol-gel method used in existing technologies to prepare hydrophobic coatings on the surface of microchannel heat exchangers often uses silane precursors that can easily generate irritating odors and corrosive substances, making it difficult to guarantee the environmental friendliness and safety of the process. In addition, there are almost no patents in the existing technology that address the improvement of the buffering performance of the bending areas of such heat exchange tubes.

[0005] Therefore, there is an urgent need to develop a new type of high-fluidity heat exchange tube with high fluid impact buffering performance and its preparation method. It is necessary to ensure the heat exchange capacity and corrosion resistance of the heat exchange tube, while also improving its fluid buffering performance and service life. Moreover, these two aspects are often complementary. Once a local area is deformed and damaged by long-term impact of high-speed fluid, it will not only affect the service life, but also lead to a decrease in the overall heat exchange uniformity. This is a problem that urgently needs to be solved. Summary of the Invention

[0006] 1. The problem to be solved

[0007] To address the problem in existing technologies that it is difficult to simultaneously achieve high heat exchange capacity and corrosion resistance with fluid buffering performance and service life, especially the latter which is currently difficult to solve effectively, this invention provides a high-throughput heat exchange tube with high fluid shock buffering performance and its preparation method.

[0008] 2. Technical Solution

[0009] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0010] This invention provides a method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance, which includes the following steps:

[0011] (1) The inner and outer surfaces of the carbon steel pipe are degreased and derusted to remove residual flux, oxide layer and oil stains and other contaminants, resulting in a cleaner carbon steel pipe surface.

[0012] (2) Mix the silicone adhesive and aluminum alloy powder in a mass ratio of 1:0.5-1:1, add them to a ball mill and ball mill, then coat them evenly on the surface of the carbon steel tube with a thickness of 50-100μm, and then dry them at 60-80℃ for 4-6 hours to obtain the heat exchange tube blank.

[0013] (3) The heat exchange tube blank is placed in a tubular furnace for brazing and sintering. The temperature is raised to 1100-1150℃ and held for 60-100 minutes. The heat exchange tube is then cooled to room temperature in the furnace to obtain the intermediate body of the heat exchange tube.

[0014] This temperature range ensures good metal bonding between the aluminum alloy and the carbon steel tube matrix, while avoiding grain growth and uneven microstructure caused by excessively high temperatures, thus facilitating subsequent ultrasonic rolling treatment.

[0015] (4) The heat exchange tube intermediate is immersed in the protective and reinforcing liquid for ultrasonic surface rolling treatment. The ultrasonic amplitude is controlled at 15-20μm. The process is repeated 50-100 times, and a static force of 28-140 Newtons is applied each time. The protective and reinforcing liquid is composed of the following components: deionized water, water-soluble cutting fluid, benzotriazole, sodium silicate, triethanolamine, and nonionic surfactant.

[0016] in:

[0017] ① Water-soluble cutting fluids have a lubricating effect;

[0018] ② The aluminum alloy layer is easily corroded under ultrasonic cavitation. This application provides dual protection by adding an appropriate ratio of benzotriazole and sodium silicate: benzotriazole forms a chelate film with Al and Zn, which inhibits electrochemical corrosion and provides good protection against the micro-impact and oxidation of ultrasonic cavitation; sodium silicate hydrolyzes to form a SiO2 gel film, which fills the micro-defects in the coating and enhances corrosion resistance. At the same time, it adjusts the pH to weak alkalinity (7.5-8.5) to inhibit the dissolution of aluminum.

[0019] ③ Triethanolamine has rust-preventing and weak-alkali-maintaining properties;

[0020] ④ Nonionic surfactants (such as Tween-80) can reduce the surface tension of water, thereby promoting ultrasonic cavitation (bubbles are easier to generate and collapse more violently), and enhancing ultrasonic rolling ability;

[0021] ⑤ The acoustic impedance of the aqueous solution formed by all the above components is similar to that of the aluminum alloy (~1.7×10). 7 kg / (m 2 Matching with ·s)) can reduce ultrasonic reflection loss.

[0022] In summary, this protective enhancement fluid has a synergistic effect of sound transmission, lubrication, corrosion protection and cavitation enhancement. It forms a dense surface structure through ultrasonic rolling, thereby improving the adhesion between the coating and the substrate.

[0023] (5) After cleaning the intermediate heat exchange tube that has been ultrasonically rolled, place it in a vacuum environment for secondary high-temperature sintering, raise the temperature to 1300-1400℃, keep it at the temperature for 30-60 minutes, and cool it to room temperature with the furnace to obtain a high-fluidity heat exchange tube with high fluid impact buffering performance.

[0024] This secondary sintering process further improves the density and stability of the coating, forming a gradient grain structure and enhancing the mechanical properties of the material.

[0025] Preferably, in step (2), the ball mill is used to ball mill for 4-6 hours to achieve a particle size of 0.5-1 μm.

[0026] Preferably, in step (2), the aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is (2-5):1; the brazing material is one or a mixture of several of Al, Cu, Zn, Mg, Ni and Mo.

[0027] Preferably, the elemental composition and weight percentage of the material used for brazing are: 70-78% Al, 10-27% Cu, 1.4-3.6% Mg, 1.1-3.2% Zn, 0.8-1.5% Ni, 0.2-1.2% Mo, with the balance being unavoidable impurities.

[0028] Preferably, in step (4), the protective enhancement liquid is composed of the following components by mass: 85-90% deionized water, 5-10% water-soluble cutting fluid, 0.2-0.5% benzotriazole, 1-2% sodium silicate, 1-2% triethanolamine, and 0.1-0.3% nonionic surfactant.

[0029] Preferably, the water-soluble cutting fluid comprises PEG and fatty acid esters in a mass ratio of (2-3):1.

[0030] Preferably, the nonionic surfactant is Tween-80.

[0031] Preferably, in step (4), the ultrasonic device used for the ultrasonic surface rolling treatment includes a container with an opening, a fixing member for fixing the heat exchange tube, a protective reinforcing liquid contained in the container, a sealing plate that seals with the opening of the container, a load application device connected to the sealing plate, an ultrasonic generator, and a vacuum pump for extracting air from the container.

[0032] Preferably, the static force applied by the load application device and the vibration force of the ultrasonic generator are both applied vertically downward by the sealing pressure plate.

[0033] The present invention also provides a high-fluidity heat exchange tube with high fluid shock buffering performance, which is prepared by any of the methods described above.

[0034] 3. Beneficial effects

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0036] (1) This invention combines brazing and sintering with ultrasonic surface rolling technology, especially the use of an ultrasonic device containing a protective and reinforcing liquid during the ultrasonic surface rolling process. Through the control of ultrasonic amplitude and repeated processing, the surface of the heat exchange tube is refined, which significantly reduces the surface roughness, reduces the friction coefficient, and improves the toughness, wear resistance and corrosion resistance of the heat exchange tube, especially at the bend. It effectively solves the problems of intergranular corrosion and fluid impact deformation leading to a decrease in matrix strength in the heat exchange tube in the prior art, and also ensures the heat exchange uniformity of the heat exchange tube.

[0037] (2) By optimizing the sintering process parameters and the ultrasonic surface rolling process, the present invention achieves a good bond between the heat exchange tube surface and the substrate, generating residual compressive stress, which effectively improves the heat exchange tube's buffering capacity and solves the problem of insufficient bonding force between the metal tube and the coating during the sandblasting process in the prior art.

[0038] (3) The present invention adopts a secondary high-temperature sintering process, which ensures the density and stability of the porous layer, while avoiding the defects that may be caused by a single sintering process, and improving the service life and reliability of the heat exchange tube.

[0039] (4) The preparation method of the present invention is simple to operate, the process is controllable, and it is easy to scale up production. It does not produce irritating odors or corrosive substances, ensuring the environmental protection and safety of the process and overcoming the safety hazards of the existing sol-gel method in the preparation of hydrophobic coatings. Moreover, the ultrasonic device and the protective enhancement liquid can be reused with almost no loss, which greatly reduces the cost. Attached Figure Description

[0040] Figure 1 This is a diagram of the apparatus used in the preparation method of a high-throughput heat exchanger tube with high fluid shock buffering performance according to the present invention;

[0041] Figure 2 This diagram illustrates the apparatus used in the preparation method of a high-fluid-impact, high-throughput heat exchanger tube according to the present invention, and shows the application of different heat exchanger tubes.

[0042] Figure 3 This is a schematic diagram of the forces acting on the inner and outer surfaces of a heat exchange tube under a partial cross-section of the ultrasonic surface vibration process of the present invention.

[0043] In the picture:

[0044] 100. Sealing plate; 200. Container; 300. Fixture; 400. Protective reinforcement fluid; 500. Heat exchange tube; 501. Aluminum alloy layer. Detailed Implementation

[0045] The more detailed description of embodiments of the invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and does not limit the description of the features and characteristics of the invention, in order to suggest the best mode for carrying out the invention and to enable those skilled in the art to practice the invention. However, it should be understood that various modifications and variations can be made without departing from the scope of the invention as defined by the appended claims. The detailed description should be considered illustrative only and not restrictive, and any such modifications and variations shall fall within the scope of the invention described herein. Furthermore, the background art is intended to illustrate the current state of research and development and significance of the technology, and is not intended to limit the invention or the scope of application of this application.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0047] The ultrasonic device used in this invention is a novel design, such as... Figure 1 and Figure 2As shown, it specifically includes a container 200 with an opening, a fixing member 300, a protective reinforcing fluid 400 contained therein, and a sealing plate 100 that seals with the container 200. It also includes a load application device, a vacuum pump, and an ultrasonic generator (not shown in the figure due to its existing common structure). The load application device is used to apply downward static and vibrational forces to the sealing plate 100; the fixing member 300 is used to install the heat exchange tube 500; the ultrasonic generator is connected to the load application device to transmit the vibrational force; the vacuum pump is connected to the cavity of the container 200 to extract air during the pressing of the sealing plate 100 until the sealing plate 100 is in contact with the liquid surface of the protective reinforcing fluid 400, so as to apply a uniform downward pressure to the liquid surface of the protective reinforcing fluid 400.

[0048] like Figure 3 As shown, the heat exchange tube 500 is filled with protective and reinforcing liquid 400 inside and out. The pressure of the sealing plate 100 by the load application device converts the vertical downward force into uniform pressure on all irregular positions of the aluminum alloy layer 501 on the inner and outer walls of the heat exchange tube 500 (here, because the size of the heat exchange tube 500 itself is generally small, the water pressure difference caused by the height difference of the heat exchange tube itself is ignored, and the surface pressure of the heat exchange tube is equal everywhere without considering the water pressure difference).

[0049] Existing ultrasonic surface rolling technology can generally only roll two-dimensional materials and cannot operate on three-dimensional irregular objects or even objects with multi-faceted rolling requirements. This application cleverly solves this problem through the aforementioned ultrasonic device.

[0050] The present invention will be further described below with reference to specific embodiments.

[0051] Example 1

[0052] This embodiment describes a method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance, employing... Figure 1 The heat exchange tube is made from shaped carbon steel tubes, including the following steps:

[0053] (i) Degrease and remove rust from the inner and outer surfaces of the carbon steel pipe to remove residual flux, oxide layer and oil stains. Wipe the surface of the carbon steel pipe 3-5 times with a mixed solution of acetone and ethanol (volume ratio of 1:1) to obtain a relatively clean carbon steel pipe surface.

[0054] (II) Mix the silicone adhesive (solid content of 40wt%) and aluminum alloy powder at a mass ratio of 1:0.7, add them to a ball mill and ball mill for 5 hours to achieve a particle size of 0.5-1μm. Then, use a spraying process to uniformly coat the carbon steel tube surface, with the coating thickness controlled at 50-80μm. After that, dry at 65℃ for 5 hours to obtain a heat exchange tube blank. The aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is 3:1. The elemental composition and weight percentage of the brazing material are: 76%Al, 15%Cu, 3.6%Mg, 2.7%Zn, 1.3%Ni, 0.8Mo, with the balance being unavoidable impurities.

[0055] (III) The heat exchange tube blank is placed in a tubular resistance furnace for brazing and sintering. The heating curve is: room temperature → 150℃ / 20min → 350℃ / 20min → 1100℃ / 30min, held for 70 minutes, and cooled to room temperature with the furnace to obtain the heat exchange tube intermediate.

[0056] (iv) The intermediate heat exchange tube is immersed in the protective and reinforcing liquid for ultrasonic surface rolling treatment. The ultrasonic amplitude is controlled at 16 μm. The process is repeated 30 times, with a static force of 32 N applied each time. The protective and reinforcing liquid is composed of the following components by mass: 88.5% deionized water, 8% water-soluble cutting fluid (PEG: polyethylene glycol monomethyl ether ketone = 2:1), 0.3% benzotriazole (BTA), 1.5% sodium silicate, 1.5% triethanolamine, and 0.2% Tween-80 (nonionic surfactant).

[0057] (v) After cleaning the intermediate heat exchange tube that has undergone ultrasonic surface rolling, place it under a vacuum of not less than 1×10⁻⁶. -3 Secondary high-temperature sintering was carried out in a vacuum environment of Pa. The heating curve was: room temperature → 200℃ / 20min → 400℃ / 20min → 1300℃ / 30min, held for 45 minutes, and then cooled to room temperature with the furnace to obtain a high-fluidity heat exchange tube with high fluid shock buffering performance.

[0058] To verify the buffering capacity of the heat exchange tube, a heat exchange tube with an average wall thickness of 1.5 mm was used as a sample. Fluorinated liquid refrigerant at 50 °C was introduced into the heat exchange tube at a flow rate of 10 m / s for 24 h of impact test. The thickness of the heat exchange tube bending zone before and after the impact test was measured. The thickness was measured at 5 points in the same bending zone and the non-uniformity (i.e., standard deviation / average value, i.e., coefficient of variation) was calculated and recorded in Table 1.

[0059] The tests showed that before the impact test, the thicknesses at five points in the bending zone of the heat exchanger tube were 1.47 mm, 1.48 mm, 1.51 mm, 1.50 mm, and 1.50 mm, respectively, with a calculated non-uniformity of 1.10%. After the impact test, the thicknesses at five points in the bending zone of the same heat exchanger tube were 1.48 mm, 1.46 mm, 1.50 mm, 1.50 mm, and 1.49 mm, respectively, with a calculated non-uniformity of 1.34%. It can be seen that the overall uniformity remains good, and no significant deformation has occurred.

[0060] Table 1. Comparison of unevenness in the heat exchanger tube bending zone of each implementation method

[0061]

[0062] Examples 2-6

[0063] The operating steps of Examples 2-6 are basically the same as those of Example 1. The main difference is that the static loads applied each time are 48 N, 72 N, 96 N, 112 N, and 140 N, respectively, to verify the effect of different static loads on the heat exchange tube under the same ultrasonic vibration load. To avoid data complexity, only the non-uniformity (i.e., standard deviation / mean, or coefficient of variation) is recorded in Table 1 thereafter.

[0064] As shown in Table 1, within the static load range of 28-140 N in Examples 1-6, the fabricated heat exchange tubes maintain a stable structure even under high-speed fluid impact. Even in areas prone to deformation due to fluid impact, such as bends, high uniformity is maintained, thus ensuring the heat transfer uniformity of the heat exchange tubes. Furthermore, the applicant found that the heat exchange tubes with static loads between 72 N and 96 N exhibited the best stability performance.

[0065] Example 7

[0066] The operation steps of Examples 2-6 are basically the same as those of Example 1. The main difference is that the following steps are used. Figure 2 The heat exchange tubes are made of carbon steel tubes of a specific shape, compared to Figure 1 The only difference is that the length and bending area of ​​the heat exchange tubes have increased.

[0067] Five measurements were taken at the same bending area, for a total of 16 measurements, and the non-uniformity (i.e., standard deviation / mean, or coefficient of variation) was recorded in Table 1. It was found that the non-uniformity before and after the experiment was slightly increased compared to Examples 1-6. This may be due to the increased data sample size leading to greater dispersion, but the overall change remained small. This indicates that increasing the size or changing the shape of the heat exchange tube does not affect the rolling and alloy forming of the aluminum alloy layer on the surface of the heat exchange tube in this application.

[0068] Comparative Example 1

[0069] This comparative example provides a method for preparing a conventional heat exchange tube, which specifically includes the following steps:

[0070] (i) Degrease and remove rust from the inner and outer surfaces of the carbon steel pipe to remove residual flux, oxide layer and oil stains. Wipe the surface of the carbon steel pipe 3-5 times with a mixed solution of acetone and ethanol (volume ratio of 1:1) to obtain a relatively clean carbon steel pipe surface.

[0071] (II) Mix the silicone adhesive (solid content of 40wt%) and aluminum alloy powder at a mass ratio of 1:0.7, add them to a ball mill and ball mill for 5 hours to achieve a particle size of 0.5-1μm. Then, use a spraying process to uniformly coat the carbon steel tube surface, with the coating thickness controlled at 50-80μm. After that, dry at 65℃ for 5 hours to obtain a heat exchange tube blank. The aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is 3:1. The elemental composition and weight percentage of the brazing material are: 76%Al, 15%Cu, 3.6%Mg, 2.7%Zn, 1.3%Ni, 0.8Mo, with the balance being unavoidable impurities.

[0072] (III) The heat exchange tube blank is placed in a tubular resistance furnace for brazing and sintering. The heating curve is: room temperature → 200℃ / 20min → 400℃ / 20min → 1300℃ / 30min, held for 115 minutes, and cooled to room temperature with the furnace to obtain the heat exchange tube.

[0073] The comparison shows that the only difference between Comparative Example 1 and Example 1 is the removal of the ultrasonic surface rolling process and the combination of the two sintering processes. The results show that the heat exchange tube has significantly reduced resistance to fluid shock buffering performance. This is because the stable aluminum alloy layer of this application was not formed on the surface of the heat exchange tube.

[0074] The present invention has been described in detail above with reference to specific exemplary embodiments. However, it should be understood that various modifications and variations can be made without departing from the scope of the invention as defined by the appended claims. The detailed description should be considered illustrative only and not restrictive, and any such modifications and variations shall fall within the scope of the invention described herein. Furthermore, the background art is intended to illustrate the current state of development and significance of the technology and is not intended to limit the present invention or the scope of application of the present application.

[0075] More specifically, although exemplary embodiments of the invention have been described herein, the invention is not limited to these embodiments, but includes any and all embodiments modified, omitted, such as combinations between various embodiments, adaptive changes, and / or substitutions, as would be apparent to those skilled in the art from the foregoing detailed description. The limitations in the claims are to be interpreted broadly as used in the language of the claims and are not limited to the examples described in the foregoing detailed description or during the implementation of this application, which should be considered non-exclusive. Any step listed in any method or process claim may be performed in any order and is not limited to the order set forth in the claims. Therefore, the scope of the invention should be determined solely by the appended claims and their legal equivalents, and not by the description and examples given above.

[0076] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. In case of conflict, the definitions in this specification shall prevail. When flow rate, power, refractive index, time, or other values ​​or parameters are expressed as ranges, preferred ranges, or a series of upper and lower preferred values, this should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether such range is disclosed individually. For example, the range 1-50 should be understood to include any number, combination of numbers, or subrange selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, or 50, as well as all decimal values ​​between the integers mentioned above, such as 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, and 1.9. Regarding subranges, specifically consider "nested subranges" extending from any endpoint of the range. For example, nested sub-ranges of the exemplary range 1-50 may include 1-10, 1-20, 1-30 and 1-40 in one direction, or 50-40, 50-30, 50-20 and 50-10 in another direction.

Claims

1. A method for preparing high fluid impact buffering performance high flux heat exchange tube, characterized in that, Includes the following steps: (1) The inner and outer surfaces of the carbon steel pipe are degreased and derusted to remove residual flux, oxide layer and oil stains and other contaminants, so as to obtain a relatively clean carbon steel pipe surface. (2) Mix the silicone adhesive and aluminum alloy powder in a mass ratio of 1:0.5-1:1, add them to a ball mill and ball mill, then coat them evenly on the surface of the carbon steel tube with a thickness of 50-100μm, and then dry them at 60-80℃ for 4-6 hours to obtain the heat exchange tube blank. (3) The heat exchange tube blank is placed in a tubular furnace for brazing and sintering, heated to 1100-1150℃, held for 60-100 minutes, and cooled to room temperature with the furnace to obtain the heat exchange tube intermediate. (4) The intermediate heat exchange tube is immersed in the protective and reinforcing liquid for sealed and pressurized ultrasonic surface rolling treatment. The ultrasonic amplitude is controlled at 15-20 μm. The process is repeated 50-100 times, and a static force of 72-96 N is applied each time. The protective and reinforcing liquid is composed of the following components: deionized water, water-soluble cutting fluid, benzotriazole, sodium silicate, triethanolamine, and nonionic surfactant. (5) After cleaning the intermediate heat exchange tube with sealed pressure ultrasonic surface rolling, place it in a vacuum environment for vacuum secondary high temperature sintering, heat it to 1300-1400℃, keep it at that temperature for 30-60 minutes, and then cool it to room temperature with the furnace to obtain a high-fluidity heat exchange tube with high fluid impact buffering performance.

2. The method of claim 1, wherein the high fluid impact buffering high flux heat exchange tube is prepared by the steps of: In step (2), the ball mill is used to ball mill for 4-6 hours to achieve a particle size of 0.5-1 μm. ​ 3. The method of claim 1, wherein the high fluid impact buffering performance high flux heat exchange tube is prepared by the steps of: In step (2), the aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is (2~5):1; the brazing material is one or a mixture of several of Al, Cu, Zn, Mg, Ni and Mo. ​ 4. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 3, characterized in that, The elemental composition and weight percentage of the material used for brazing are as follows: 70-78% Al, 10-27% Cu, 1.4-3.6% Mg, 1.1-3.2% Zn, 0.8-1.5% Ni, 0.2-1.2% Mo, with the balance being unavoidable impurities.

5. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 1, characterized in that, In step (4), the protective enhancement fluid is composed of the following components by mass: 85-90% deionized water, 5-10% water-soluble cutting fluid, 0.2-0.5% benzotriazole, 1-2% sodium silicate, 1-2% triethanolamine, and 0.1-0.3% nonionic surfactant.

6. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 5, characterized in that, The water-soluble cutting fluid comprises PEG and fatty acid esters in a mass ratio of (2~3):

1.

7. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 5, characterized in that, The nonionic surfactant is Tween-80.

8. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 1, characterized in that, In step (4), the ultrasonic device used for ultrasonic surface rolling treatment includes a container with an opening, a fixing member for fixing the heat exchange tube, a protective reinforcing liquid contained in the container, a sealing plate that seals with the opening of the container, a load application device connected to the sealing plate, an ultrasonic generator, and a vacuum pump for extracting air from the container.

9. The method for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 8, characterized in that, The static force applied by the load application device and the vibration force from the ultrasonic generator are both applied vertically downwards by the sealing pressure plate.

10. A high-flux heat exchanger tube with high fluid shock buffering performance, characterized in that, It is prepared by the method of any one of claims 1 to 9.

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