Heat exchange tube with high fluid impact buffering performance and high flux and preparation method thereof

Abstract

The invention discloses a heat exchange tube with high fluid impact buffering performance and high flux and a preparation method thereof, and belongs to the technical field of preparation of heat exchange tubes. According to the method, the brazing sintering and ultrasonic surface rolling technology is combined, particularly, an ultrasonic device containing protection enhancing liquid is used in the ultrasonic surface rolling process, fine treatment on the surface of the heat exchange tube is achieved through ultrasonic amplitude control and repeated machining, the surface roughness is remarkably reduced, the friction coefficient is reduced, and the service life of the heat exchange tube is prolonged. The toughness, the abrasion resistance and the corrosion resistance of the heat exchange tube, especially the bending position are improved, the problem that in the prior art, intergranular corrosion and fluid impact deformation of the heat exchange tube are prone to occurring, and consequently the strength of a base body is reduced is effectively solved, and the heat exchange uniformity of the heat exchange tube is guaranteed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of heat exchange pipe preparation, and more particularly relates to a high-fluid-impact-buffering high-flux heat exchange pipe and a preparation method thereof. BACKGROUND

[0002] The high-flux heat exchange pipe is a key element of a high-flux heat exchanger, and has a porous layer structure with a high-density of pore connections on the surface, which can not only increase the heat exchange area, but also greatly increase the number of vaporization cores and significantly improve the boiling heat transfer capacity. At present, the sintering type high-flux heat exchange pipe is the main preparation method, which sinters a thin layer of porous surface high-efficiency heat exchange pipe with a specific structure on the surface of an ordinary heat exchange pipe, has become the most remarkable pipe-shell heat exchange element in strengthening the boiling heat transfer effect, and is widely used in engineering fields such as oil refining, petrochemical, and chemical industry.

[0003] However, the existing sintering type high-flux heat exchange pipe still has some problems. First, a too high sintering temperature will reduce the mechanical properties of the pipe, and reducing the sintering temperature will 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 uneven pore size distribution and is difficult to control, and the matrix strength and heat exchange performance will decrease after being corroded due to intergranular corrosion.

[0004] In addition, high-speed heat exchange fluid is usually required to flow through the heat exchange pipe to exchange heat with the heat load or cold load, and the heat exchange pipe is usually made into a coil structure to save installation space, which inevitably causes the bending area of the heat exchange pipe to be impacted by the high-speed fluid. At this time, the fluid buffering performance of the heat exchange pipe is particularly important. Moreover, in the prior art, the silane precursor used in the sol-gel method for preparing a hydrophobic coating on the surface of a micro-channel heat exchanger can easily produce irritating odor and corrosive substances, making it difficult to ensure the environmental protection and safety of the processing process. In addition, there is almost no patent in the prior art for improving the buffering performance of the bending area of such a heat exchange pipe.

[0005] Therefore, it is urgent to develop a new type of high-fluid-impact-buffering high-flux heat exchange pipe and a preparation method thereof, which not only ensures the heat exchange capacity and corrosion resistance of the heat exchange pipe, but also improves the fluid buffering performance and service life of the heat exchange pipe. Moreover, the two are often complementary to each other. Once a local area is deformed and damaged by long-term impact of high-speed fluid, not only the service life is affected, but also the overall heat exchange uniformity is reduced, which is a difficult problem to be solved at present. SUMMARY

[0006] 1. Problems to be solved

[0007] In view of the problem that the heat exchange capacity and corrosion resistance and fluid buffer resistance and service life of the heat exchange tube are difficult to be compatible in the prior art, especially the latter is difficult to be effectively solved at present, the application provides a high fluid impact buffer performance high flux heat exchange tube and a preparation method thereof.

[0008] 2. Technical scheme

[0009] In order to solve the above problems, the technical scheme adopted by the application is as follows:

[0010] The application provides a high fluid impact buffer performance high flux heat exchange tube preparation method, which comprises the following steps:

[0011] (1) The inner and outer surfaces of the carbon steel tube are subjected to oil removal and rust removal treatment to remove contaminants such as residual brazing agent, oxide layer and oil stains on the surface, so that a relatively clean carbon steel tube surface is obtained;

[0012] (2) The organic silicone adhesive and the aluminum alloy powder are mixed in a mass ratio of 1:0.5-1:1, are added into a ball mill for ball milling, are then uniformly coated on the surface of the carbon steel tube with a thickness controlled within 50-100 μm, and are then dried at 60-80 ℃ for 4-6 hours to obtain a heat exchange tube rough blank;

[0013] (3) The heat exchange tube rough blank is placed into a tubular furnace for brazing and sintering, is heated to 1100-1150 ℃, is kept at the temperature for 60-100 minutes, and is cooled to room temperature along with the furnace to obtain a heat exchange tube intermediate body;

[0014] The temperature range can ensure that the aluminum alloy and the carbon steel tube substrate form a good metal bond, and can avoid grain growth and uneven structure caused by excessively high temperature, so as to facilitate subsequent ultrasonic rolling treatment;

[0015] (4) The heat exchange tube intermediate body is immersed in a protection enhancement liquid for ultrasonic surface rolling treatment, the ultrasonic amplitude is controlled within 15-20 μm, the repeated processing is 50-100 times, and the static force applied each time is 28-140 N, and the protection enhancement liquid is composed of the following components: deionized water, water-soluble cutting fluid, benzotriazole, sodium silicate, triethanolamine and non-ionic surfactant;

[0016] Among them:

[0017] ① The water-soluble cutting fluid has a lubricating effect;

[0018] ② The aluminum alloy layer is easy to be corroded under ultrasonic cavitation, and the application realizes double protection by adding benzotriazole and sodium silicate in a proper ratio: the benzotriazole forms a chelate film with Al and Zn, inhibits electrochemical corrosion, and has good protection against micro-impact and oxidation of ultrasonic cavitation; the sodium silicate hydrolyzes to form a SiO2 gel film, fills the micro-defects of the plating layer, enhances the corrosion resistance, adjusts the pH to weak alkaline (7.5-8.5), and inhibits the dissolution of aluminum;

[0019] ③triethanolamine has anti-rust and maintain weak base effect;

[0020] ④non-ionic surfactant (such as Tween-80) can reduce the surface tension of water, thereby promoting ultrasonic cavitation (bubbles more easily generated, more intense collapse), enhanced ultrasonic rolling ability;

[0021] ⑤all the components of the aqueous solution of acoustic impedance and aluminum alloy (1.7 x 10 7 kg / (m 2 ·s)) match, can reduce ultrasonic reflection loss.

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

[0023] (5) the ultrasonic surface rolling of the heat exchange tube is completed, and then the heat exchange tube is cleaned and placed in a vacuum environment for secondary high-temperature sintering, the temperature is raised to 1300-1400℃, the temperature is kept for 30-60 minutes, and the furnace is cooled to room temperature, thereby obtaining a high-fluid-impact-buffering high-flux heat exchange tube.

[0024] The secondary sintering process further improves the density and stability of the coating, forms a gradient distribution of grain structure, and enhances the mechanical properties of the material.

[0025] Preferably, in the (2) step, the ball milling is performed in the ball mill for 4-6 hours, so that the particle size reaches 0.5-1 μm.

[0026] Preferably, in the (2) step, the aluminum alloy powder comprises 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, in the brazing material, the weight percentage of each element component is as follows: 70-78% Al, 10-27% Cu, 1.4-3.6% Mg, 1.1-3.2% Zn, 0.8-1.5% Ni, and 0.2-1.2 Mo, and the balance is inevitable impurities.

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

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

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

[0031] Preferably, in the (4) step, the ultrasonic surface roller pressing treatment uses an ultrasonic device including a container with an opening, a fixing member for fixing the heat exchange tube, a protective enhancement liquid contained in the container, a sealing pressure plate sealingly matched with the opening of the container, a load applying device connected with the sealing pressure plate, and an ultrasonic wave generator, and a vacuum pump for air extraction of the container.

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

[0033] The present application also provides a high fluid impact buffering performance high flux heat exchange tube prepared by any of the above methods.

[0034] 3. Beneficial effects

[0035] Compared with the prior art, the present application has the following beneficial effects:

[0036] (1) The present application combines brazing sintering with ultrasonic surface roller pressing technology, especially uses an ultrasonic device containing a protective enhancement liquid in the ultrasonic surface roller pressing process, and realizes fine processing of the surface of the heat exchange tube through control of the amplitude of ultrasonic waves and repeated processing, significantly reduces the surface roughness, reduces the friction coefficient, improves the toughness, wear resistance and corrosion resistance of the heat exchange tube, especially at the bending part, effectively solves the problems of intergranular corrosion and fluid impact deformation of the heat exchange tube in the prior art, and ensures the heat exchange uniformity of the heat exchange tube.

[0037] (2) The present application optimizes the sintering process parameters and the ultrasonic surface roller pressing process, realizes good bonding between the surface of the heat exchange tube and the substrate, produces residual compressive stress, effectively improves the buffering resistance of the heat exchange tube, and solves the problem of insufficient bonding force between the metal tube and the coating in the sandblasting process in the prior art.

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

[0039] (4) The preparation method of the present application is simple to operate, controllable in process, easy to scale up, and does not produce irritating odor and corrosive substances, ensuring the environmental protection and safety of the processing process, overcoming the safety hazards existing in the preparation of hydrophobic coating by the sol-gel method. Moreover, the ultrasonic device and the protective enhancement liquid can be reused almost without loss, greatly reducing the cost. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 The device diagram used for the preparation method of the high fluid impact buffering performance high flux heat exchange pipe of the present application;

[0041] Figure 2 The device diagram used for the preparation method of the high fluid impact buffering performance high flux heat exchange pipe of the present application is a schematic diagram for use of different heat exchange pipes;

[0042] Figure 3 The internal and external surface stress schematic diagram of the heat exchange pipe under the ultrasonic surface vibration process of the present application.

[0043] In the figure:

[0044] 100, sealing pressure plate; 200, containing device; 300, fixing part; 400, protective enhancement liquid; 500, heat exchange pipe; 501, aluminum alloy layer. DETAILED DESCRIPTION

[0045] The following more detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but merely to provide illustrative examples and descriptions of the features and characteristics of the application to those skilled in the art to enable them to best utilize the application and to set forth the best mode of practicing the application. However, it is to be understood that various modifications and variations can be made to the present application without departing from the scope of the application as defined in the appended claims. The detailed description is merely intended to illustrate the application and is not to be construed as limiting the application, and if there are any such modifications and variations, they will all fall within the scope of the present application described herein. Furthermore, the background is intended to explain the state of the art and significance of the present application, and is not intended to limit the present application or the field of application of the present 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 the present application belongs; the terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application.

[0047] The ultrasonic device used in the present application is a new design of the present application, 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) mixing the silicone adhesive (solid content 40wt%) and aluminum alloy powder in a mass ratio of 1:0.7, adding into a ball mill for ball milling for 5 hours to make the particle size reach 0.5-1 μm, then uniformly coating on the surface of the carbon steel pipe by using a spraying process, controlling the coating thickness at 50-80 μm, then drying at 65℃ for 5 hours to obtain the heat exchange pipe rough blank; the aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is 3:1, and the element composition and weight percentage of the material used for brazing are as follows: 76% Al, 15% Cu, 3.6% Mg, 2.7% Zn, 1.3% Ni, 0.8 Mo, and the balance is inevitable impurities.

[0055] (iii) placing the heat exchange pipe rough blank into a tubular resistance furnace for brazing and sintering, and the temperature rising curve is as follows: room temperature→150℃ / 20min→350℃ / 20min→1100℃ / 30min, keeping the temperature for 70 minutes, and cooling to room temperature with the furnace to obtain the heat exchange pipe intermediate body;

[0056] (iv) immersing the heat exchange pipe intermediate body into a protective enhancement liquid for ultrasonic surface rolling treatment, controlling the ultrasonic amplitude at 16 μm, repeating the processing for 30 times, and applying static force of 32 N each time, and the protective enhancement liquid is composed of the following mass components: deionized water 88.5%, water-soluble cutting fluid (PEG: polyethylene glycol monomethyl ether ether ketone = 2:1) 8%, benzotriazole (BTA) 0.3%, sodium silicate 1.5%, triethanolamine 1.5%, Tween-80 (non-ionic surfactant) 0.2%;

[0057] (v) after cleaning the heat exchange pipe intermediate body after the ultrasonic surface rolling, placing it in a vacuum environment with a vacuum degree of not less than 1×10 -3 Pa for secondary high-temperature sintering, and the temperature rising curve is as follows: room temperature→200℃ / 20min→400℃ / 20min→1300℃ / 30min, keeping the temperature for 45 minutes, and cooling to room temperature with the furnace to obtain the high-fluid-impact-buffering-performance high-flux heat exchange pipe.

[0058] In order to verify the buffering capacity of the heat exchange pipe, the heat exchange pipe with an average wall thickness of 1.5 mm is used as a sample, a fluorinated liquid coolant at 50℃ is passed into the heat exchange pipe at a flow rate of 10 m / s for impact test for 24 hours, the thickness of the bending area of the heat exchange pipe before and after the impact test is measured, the thickness of 5 places of the same bending area is measured respectively, and the unevenness (i.e. standard deviation / average value, i.e. coefficient of variation) is calculated and recorded in Table 1.

[0059] After the test, the thicknesses of the bending area 5 of the heat exchange tube before the impact test were 1.47 mm, 1.48 mm, 1.51 mm, 1.50 mm and 1.50 mm, respectively, and the calculated unevenness was 1.10%. After the impact test, the thicknesses of the same bending area of the heat exchange tube were 1.48 mm, 1.46 mm, 1.50 mm, 1.50 mm and 1.49 mm, respectively, and the calculated unevenness was 1.34%. It can be seen that the overall uniformity is still good and no large deformation occurs.

[0060] Table 1: Comparison of unevenness of the bending area of the heat exchange tube of each embodiment

[0061]

[0062] Examples 2-6

[0063] The operation steps of Examples 2-6 are basically the same as those of Example 1, and the main difference is that the static load applied each time is 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 complex data, only the unevenness (i.e. standard deviation / average value, i.e. coefficient of variation) is recorded in Table 1.

[0064] As can be seen from Table 1, within the static load range of 28-140 N of Examples 1-6, the heat exchange tube prepared can still maintain a stable structure under high-speed fluid impact, and even the bending area which is most susceptible to deformation by fluid impact can also ensure a high uniformity, thereby ensuring the heat exchange uniformity of the heat exchange tube. In addition, the applicant found that the heat exchange tube has the best stability when the static load is between 72 N and 96 N.

[0065] Example 7

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

[0067] The same 5 measurements are taken for the same bending area, and a total of 16 measurements are taken, and the unevenness (i.e. standard deviation / average value, i.e. coefficient of variation) is recorded in Table 1. It is found that the unevenness before and after the experiment is slightly increased compared to Examples 1-6, which may be due to the larger dispersion caused by the increase in the number of data samples, but the overall change is still not large. This shows that the increase in the size of the heat exchange tube or the change in the shape does not affect the rolling + alloy forming of the aluminum alloy layer on the surface of the heat exchange tube.

[0068] Comparative Example 1

[0069] The present comparative example provides a preparation method of a conventional heat exchange tube, which specifically comprises the following steps:

[0070] (I) The inner and outer surfaces of the carbon steel pipe are subjected to oil removal and rust removal treatment to remove surface residual flux, oxide layer, oil stains and other contaminants. A mixed solution of acetone and ethanol (volume ratio 1:1) is used to wipe the surface of the carbon steel pipe 3-5 times to obtain a relatively clean carbon steel pipe surface;

[0071] (II) The organic silicone adhesive (solid content 40wt%) and aluminum alloy powder are mixed in a mass ratio of 1:0.7, added to a ball mill and ball milled for 5 hours to obtain a particle size of 0.5-1 μm. Then a spraying process is used to uniformly coat the surface of the carbon steel pipe, with the coating thickness controlled at 50-80 μm. After drying at 65°C for 5 hours, a heat exchange tube blank is obtained. The aluminum alloy powder includes aluminum and brazing material, and the weight ratio of aluminum to brazing material is 3:1. The elements and their weight percentages in the brazing material are as follows: 76% Al, 15% Cu, 3.6% Mg, 2.7% Zn, 1.3% Ni, 0.8 Mo, and the balance is unavoidable impurities.

[0072] (III) The heat exchange tube blank is placed in a tubular resistance furnace for brazing and sintering. The temperature rising curve is: room temperature→200°C / 20min→400°C / 20min→1300°C / 30min. The temperature is kept for 115 minutes, and the furnace is cooled to room temperature. A heat exchange tube is obtained.

[0073] As can be seen, the difference between Example 1 and Comparative Example 1 is that the ultrasonic surface rolling process is removed and the two sintering processes are combined into one. The result shows that the fluid impact buffering performance of the heat exchange tube prepared is significantly reduced, which is caused by the fact that the stable aluminum alloy layer is not formed on the surface of the heat exchange tube.

[0074] The application has been described in detail above in connection with specific exemplary embodiments. However, it should be understood that various modifications and variations can be made without departing from the scope of the application defined by the appended claims. The detailed description is merely illustrative and not restrictive, and if there are any such modifications and variations, they will all fall within the scope of the application described herein. In addition, the background is intended to explain the state of the art and significance of the present technology, and is not intended to limit the present application or the field of application of the present application.

[0075] More specifically, although illustrative embodiments of the application have been described herein, the present application should be understood to include any and all embodiments falling within the scope of the application as defined by the appended claims, and their equivalents. The limitations in the claims are to be construed as limiting only to the precise language used in the claims. Accordingly, the breadth and scope of the present application should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. Any and all limitations which can be present in any one of the foregoing aspects should be seen as applicable to each and every aspect of the present application. Thus, the breadth and scope of the present application should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.

[0076] 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 application belongs. If there is a conflict between the definitions in the specification and those in the accompanying claims, the definitions in the claims should be construed as aligning the claim with the specification. Flow rates, power, refractive indices, times, or other values or parameters expressed in a range, preferably a range, or a series of upper preferred values and lower preferred values, should be interpreted as a disclosure of all ranges formed from any of the upper or lower values of any range or preferred value, whether or not the range is expressly disclosed. For example, a range of 1-50 should be interpreted to include a disclosure of any number from the group consisting of 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, combinations of numbers from the group, or subranges, as well as all decimal values between the integers, e.g., 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, and 1.9. With respect to subranges, "nested subranges" extending from either end of a range are specifically contemplated. For example, exemplary nested subranges of the range 1-50 can include 1-10, 1-20, 1-30, and 1-40 in one direction, or 50-40, 50-30, 50-20, and 50-10 in the other direction.

Claims

1. A method for fabricating a high-fluidity heat exchanger tube with high fluid shock buffering performance, 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. The temperature is raised to 1100-1150℃ and held for 60-100 minutes. The blank is then cooled to room temperature in the furnace to obtain the intermediate heat exchange tube. (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. (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.

2. 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 (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 for preparing a high-fluidity heat exchanger tube with high fluid shock buffering performance according to claim 1, characterized in that, 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 1, 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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