Tailless package heat pipe manufacturing process and tailless package heat pipe manufactured by the same

Abstract

The present invention belongs to the technical field of heat exchange equipment, and specifically relates to a tailless packaged heat pipe manufacturing process and a tailless packaged heat pipe manufactured by the same, and the tailless packaged heat pipe manufacturing process comprises the following steps: S1, preparing a mixture, S2, sintering; S3, pore making treatment; S4, making an anti-wetting coating; S5, heat diffusion; S6, welding an isolation net; S7, setting a getter; S8, preparing a head 1; S9, preparing a head 2; S10, making a gas barrier coating; S11, heat treatment; S12, making an anti-leakage layer. The tailless packaged heat pipe comprises a heat pipe, and the heat pipe comprises a heat pipe fitting, and a head 1 and a head 2 are respectively arranged at both ends of the heat pipe fitting, an isolation net is arranged inside the heat pipe fitting, an anti-wetting coating is arranged on the isolation net, a gas barrier coating is arranged on the head 1 and the head 2, and an anti-leakage layer is arranged outside the gas barrier coating. The present invention solves the problem of residual tail pipes existing in the manufacture of heat pipes and prolongs the service life of the heat pipes.

Description

Technical Field

[0001] The invention belongs to the technical field of heat exchange equipment, and in particular relates to a tailless packaged heat pipe manufacturing process and a tailless packaged heat pipe manufactured by the same. Background Art

[0002] During the manufacturing process of heat pipes, usually both ends are welded and sealed first, then the tail pipe is reserved, and then the working medium is filled into the heat pipe, and then the vacuum operation is performed, and then the tail pipe is clamped and flattened, and finally the tail pipe is melt-welded. However, due to the sealing requirements, the tail pipe will retain a length of 30~50mm on the finished heat pipe, occupying valuable heat exchange space. At the same time, there are molten welds at the tail of the tail pipe and the sealing parts at both ends. The metallographic structure of these molten welds is inconsistent with the metallographic structure of the heat pipe body. When the heat pipe is used in a high temperature environment with hydrogen and helium, hydrogen and helium will diffuse through these welds, which will cause the internal air pressure of the heat pipe to increase, causing the performance of the heat pipe to decrease, and even cause failure.

[0003] In addition, after long-term use, the internal vacuum degree of the heat pipe will usually decrease, increasing the internal thermal resistance of the heat pipe. When the vacuum environment inside the heat pipe is destroyed, the working medium in the heat pipe is more likely to react with the incoming oxygen to cause oxidation, aggravating the corrosion of the inner wall of the heat pipe, which will not only cause the heat pipe to fail completely, but also bring safety hazards.

[0004] Chinese patent CN117490458A provides a mechanically assembled tailless packaged heat pipe and a manufacturing method thereof, wherein the heat pipe comprises an upper end of the heat pipe, a lower end of the heat pipe and a mechanically assembled docking assembly, wherein the upper end of the heat pipe and the lower end of the heat pipe are connected and sealed by the mechanically assembled docking assembly, wherein a steam chamber is arranged in the upper end of the heat pipe and the lower end of the heat pipe, wherein a working medium is distributed in the steam chamber, and an upper layer of liquid wick is arranged on the inner wall of the inner chamber of the upper end of the heat pipe, and a lower layer of liquid wick is arranged on the inner wall of the lower end of the heat pipe. The above patent removes the tail pipe part of the heat pipe, which can better realize the sealing of the heat pipe, but the heat pipe is a mechanically assembled tailless packaged heat pipe, and its strength stability is poor when subjected to large external force, vibration or long-term complex working conditions, and at the same time, the sealing performance of the mechanically assembled seal will decrease due to the aging of the connector, and it cannot be used for a long time. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a tailless packaged heat pipe manufacturing process, which solves the problem of residual tail pipes existing in the current heat pipe manufacturing, and at the same time optimizes the vacuum environment inside the heat pipe, ensuring that the heat pipe maintains a high vacuum state for a long time, thereby ensuring the stability and reliability of the heat pipe during long-term operation, extending the service life of the heat pipe, and improving the working performance of the heat pipe; the present invention also provides a tailless packaged heat pipe.

[0006] To solve the above problems, the technical solution adopted by the present invention is:

[0007] A process for manufacturing a tailless packaged heat pipe comprises the following steps:

[0008] S1. preparing a mixture: mixing nickel or chromium metal powder, zirconium oxide powder and aluminum powder to form a mixture;

[0009] S2, sintering: placing the mixture in a mesh mold, and sintering the mixture under vacuum or inert gas protection conditions to form a separator;

[0010] S3, pore forming treatment: after the isolation plate is cooled, the isolation plate is immersed in an alkaline solution of sodium hydroxide or potassium hydroxide to remove the aluminum powder in the isolation plate, so that the isolation plate forms an isolation net with gas microporous channels;

[0011] S4, making an anti-wetting coating: vapor-depositing titanium metal vapor on the isolation net, the titanium metal is adsorbed and diffused on the surface of the isolation net to form a transition interface, and then vapor-depositing zirconium oxide vapor, the zirconium oxide and the titanium metal are combined to form an oxide interface, and the transition interface connects the isolation net and the oxide interface respectively;

[0012] S5. Thermal diffusion: Place the isolation net in a heat treatment furnace and perform thermal diffusion treatment on the isolation net under vacuum or inert gas protection conditions;

[0013] S6. Welding isolation net: Weld the isolation net to the inner wall of the heat pipe fitting at a distance of 10-100mm from one end of the heat pipe fitting. The isolation net and one end of the heat pipe fitting form an air suction chamber, and the isolation net and the other end of the heat pipe fitting form a working chamber. The length of the working chamber is greater than the length of the air suction chamber.

[0014] S7, setting a getter: setting a getter in the getter chamber;

[0015] S8, preparing a sealing head 1: under vacuum conditions, vacuum hot spinning and sealing one end of the heat pipe fitting close to the suction chamber to form a sealing head 1;

[0016] S9, preparing the second end cap: fixing the alkali metal reflux net in the working chamber, filling the working chamber with the alkali metal working medium, and vacuum hot spinning sealing the end of the heat pipe fitting away from the suction chamber to form the second end cap;

[0017] S10, making a gas barrier coating: platinum metal is plated on the surface of the first and second end caps to form a gas barrier coating;

[0018] S11, heat treatment: placing the first and second end caps in a heat treatment furnace, and heat treating the first and second end caps under vacuum or inert gas protection conditions;

[0019] S12, making an anti-leakage layer: diffusion welding the hot-spun alloy head on the surface of the head 1 and the head 2 to form an anti-leakage layer.

[0020] Furthermore, in step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 10-80%, the mass content ratio of aluminum powder is 5-30%, and the balance is zirconium oxide powder.

[0021] Furthermore, in step S2, the sintering temperature is 300-1100°C, the sintering time is 0.5-1 hour, and the sintering pressure is 0.1-10 MPa; in step S3, the micropore diameter of the gas microporous channel is 0.1-500 μm.

[0022] Furthermore, in step S4, the thickness of the transition interface is 50-500 nm, and the thickness of the oxide interface is 50-500 nm.

[0023] Furthermore, in step S5, the thermal diffusion treatment temperature is 200-1000° C., and the thermal diffusion treatment time is 0.5-1 hour.

[0024] Furthermore, in step S5, the thermal diffusion treatment temperature is 500-800°C.

[0025] Furthermore, in step S7, the getter uses zirconium metal as an active component and aluminum metal as a synthetic framework component, and the getter is a zirconium-aluminum 16-ring getter, in which the mass of zirconium metal accounts for 84% of the total mass of the getter, and the mass of aluminum metal accounts for 16% of the total mass of the getter.

[0026] Further, in step S9, the alkali metal working medium is sodium, potassium or lithium; in step S10, the thickness of the gas barrier coating is 0.01-0.05 mm;

[0027] Further, in step S11, the heat treatment temperature is 600-1000°C, and the heat treatment time is 0.5-1 hour; in step S12, the thickness of the hot-spun alloy head is 0.1-0.5 mm, the material of the hot-spun alloy head is nickel metal, chromium metal or iron metal, and the inner surface of the hot-spun alloy head is pre-plated with a platinum metal coating, and the thickness of the platinum metal coating is 0.05-100 μm. The hot-spun alloy head is made by a hot spinning process. During the diffusion welding process of the hot-spun alloy head, the hot-spun alloy head is more likely to undergo interface metallographic diffusion with the gas barrier coating on the surface of the head 1 7 and the head 2 8, so that the hot-spun alloy head and the gas barrier coating form a firm bond at the interface.

[0028] A tailless packaged heat pipe manufactured by a tailless packaged heat pipe manufacturing process comprises a heat pipe, the heat pipe comprises a heat pipe fitting, a first end cap and a second end cap are respectively arranged at both ends of the heat pipe fitting, an isolation net is arranged inside the heat pipe fitting, an anti-wetting coating is arranged on the isolation net, an air suction chamber is arranged between the isolation net and the first end cap, a getter is arranged in the air suction chamber, a working chamber is arranged between the isolation net and the second end cap, an alkali metal reflux net is arranged in the working chamber, a gas barrier coating is arranged on the first end cap and the second end cap, and an anti-leakage layer is arranged outside the gas barrier coating.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) The vacuum hot spinning process is used to seal the ends of the heat pipe, which can prevent external gas from mixing into the heat pipe and keep the heat pipe stable during long-term operation. At the same time, sealing the ends of the heat pipe in a vacuum environment can make the sealing surface smoother and more uniform, reduce the occurrence of defects such as pores and cracks, and improve the sealing quality.

[0031] (2) The vacuum hot spinning process causes the ends of the heat pipe to undergo plastic deformation under high temperature and pressure, making the end seals more secure, ensuring the structural integrity of the heat pipe and improving its reliability and durability.

[0032] (3) The isolation net can prevent alkali metal vapor from entering the getter chamber, protecting the getter from corrosion by alkali metals, thereby ensuring that the getter can function effectively for a long time; the isolation net is formed by sintering the mixture, has good structural stability, and can withstand temperature changes and pressure fluctuations during the operation of the heat pipe.

[0033] (4) Titanium metal vapor is vapor-deposited on the isolation net, and titanium metal is adsorbed and diffused on the surface of the isolation net to form a transition interface, and zirconium oxide vapor is vapor-deposited, and zirconium oxide combines with titanium metal to form an oxide interface; the transition interface connects the isolation net and the oxide interface respectively, and the transition interface and the oxide interface form a double-interface anti-wetting coating, so the isolation net and titanium metal, titanium metal and zirconium oxide form a stable protection system to prevent alkali metal vapor from entering the suction chamber; the isolation net contains nickel or chromium metal and zirconium oxide, and the nickel or chromium metal and titanium metal are attracted to each other through metal bonds and diffuse with each other, which increases the adsorption force between the isolation net and the transition interface, and the zirconium oxide in the oxide interface diffuses with the zirconium oxide in the isolation net, which increases the adsorption force between the isolation net, the transition interface and the oxide. The anti-wetting coating improves the isolation net's anti-wetting ability to alkali metals, making the isolation net less likely to be damaged or fail under the scouring of alkali metal vapor and high temperature, thereby extending the service life of the isolation net.

[0034] (5) Gas barrier coatings are provided at both ends of the heat pipe, which can protect the heat pipe from the erosion of corrosive gases in the external environment, extend the service life of the heat pipe, and improve the overall durability of the heat pipe. Platinum metal coating and gas barrier coating not only play the role of easy diffusion and fusion of metallographic structures, but also have the effect of hydrogen element barrier, preventing the failure of both ends of the heat pipe due to hydrogen embrittlement.

[0035] (6) The anti-leakage layer is welded at both ends of the heat pipe using diffusion welding technology, and the welding quality is high. During the use of the heat pipe, the anti-leakage layer will not be easily peeled off due to temperature changes, vibration or other external forces.

[0036] The present invention solves the problem of residual tail pipe in the current heat pipe manufacturing, and at the same time optimizes the vacuum environment inside the heat pipe, ensuring that the heat pipe maintains a high vacuum state for a long time, thereby ensuring the stability and reliability of the heat pipe during long-term operation, extending the service life of the heat pipe, and improving the working performance of the heat pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the structure of the heat pipe in the present invention;

[0038] Figure 2 is an exploded view of the heat pipe of the present invention;

[0039] Figure 3 It is a structural schematic diagram of the isolation net in the present invention;

[0040] In the figure:

[0041] 1. Heat pipe; 2. Working chamber; 3. Suction chamber; 4. Isolation net; 5. Alkali metal reflux net; 6. Heat pipe fittings; 7. End cap 1; 8. End cap 2. DETAILED DESCRIPTION

[0042] The present invention is specifically described and illustrated below in conjunction with embodiments.

[0043] Example 1

[0044] like Figure 1-3 As shown, the tailless package heat pipe manufacturing process comprises the following steps:

[0045] S1. preparing a mixture: mixing nickel or chromium metal powder, zirconium oxide powder and aluminum powder to form a mixture;

[0046] S2, sintering: placing the mixture in a mesh mold, and sintering the mixture under vacuum or inert gas protection conditions to form a separator;

[0047] S3, pore forming treatment: after the isolation plate is cooled, the isolation plate is immersed in an alkaline solution of sodium hydroxide or potassium hydroxide to remove aluminum powder in the isolation plate, so that the isolation plate forms an isolation net 4 with gas microporous channels;

[0048] S4, making an anti-wetting coating: vapor-depositing titanium metal vapor on the isolation net 4, the titanium metal is adsorbed and diffused on the surface of the isolation net 4 to form a transition interface, and then vapor-depositing zirconium oxide vapor, the zirconium oxide and the titanium metal are combined to form an oxide interface, and the transition interface connects the isolation net 4 and the oxide interface respectively;

[0049] S5, thermal diffusion: placing the isolation net 4 in a heat treatment furnace, and performing thermal diffusion treatment on the isolation net 4 under vacuum or inert gas protection conditions;

[0050] S6, welding isolation net 4:

[0051] Remove impurities from the inner wall of the heat pipe fitting 6 and the surface of the isolation net 4, weld the isolation net 4 to the inner wall of the heat pipe fitting 6 at a distance of 10 to 100 mm from one end of the heat pipe fitting 6, and perform non-destructive testing on the welding part after welding; the isolation net 4 and one end of the heat pipe fitting 6 form an air suction chamber 3, and the isolation net 4 and the other end of the heat pipe fitting 6 form a working chamber 2, and the length of the working chamber 2 is greater than the length of the air suction chamber 3;

[0052] S7, setting a getter: setting a getter in the getter chamber 3, wherein the getter has titanium metal or zirconium metal as an active component and iron metal or aluminum metal as a synthetic framework component;

[0053] S8, preparation of head 7:

[0054] Clean the end of the heat pipe fitting 6 close to the air suction chamber 3 to remove impurities on the surface;

[0055] The spinning machine performs hot spinning under a vacuum chamber, places the heat pipe fitting 6 on the working table of the spinning machine, heats the end of the heat pipe fitting 6 close to the suction chamber 3 to a required temperature, starts the spinning machine, and spins the end of the heat pipe fitting 6 close to the suction chamber 3 to form a head 7;

[0056] After the sealing is completed, the appearance of the end cap 7 is checked. If an appearance defect is found, the end cap 7 needs to be repaired. If no appearance defect is found, the subsequent steps are carried out;

[0057] S9, preparation of head 2 8:

[0058] The alkali metal reflux net 5 is fixedly arranged in the working chamber 2, and the alkali metal working medium is filled into the working chamber 2;

[0059] Clean the end of the heat pipe fitting 6 away from the air suction chamber 3 to remove impurities on the surface;

[0060] The spinning machine performs hot spinning in a vacuum chamber, places the heat pipe fitting 6 on the workbench of the spinning machine, heats the end of the heat pipe fitting 6 away from the suction chamber 3 to a desired temperature, starts the spinning machine, and spins the end of the heat pipe fitting 6 away from the suction chamber 3 to form a second end cap 8;

[0061] After the sealing is completed, the appearance of the second head 8 is checked. If appearance defects are found, the second head 8 needs to be repaired. If no appearance defects are found, the surfaces of the first head 7 and the second head 8 are smoothed and spun;

[0062] S10. Making gas barrier coating:

[0063] Clean the end cap 1 7 and the end cap 2 8 to remove impurities on the surface of the end cap 1 7 and the end cap 2 8;

[0064] The cleaned end cap 1 7 and end cap 2 8 are immersed in a plating solution containing platinum ions respectively, and current is applied to the plating solution through electrodes, so that the platinum ions in the plating solution form a gas barrier coating on the surface of the end cap 1 7 and end cap 2 8;

[0065] S11, heat treatment: placing the first end cap 7 and the second end cap 8 in a heat treatment furnace, and heat treating the first end cap 7 and the second end cap 8 under vacuum or inert gas protection conditions;

[0066] S12. Making anti-leakage layer:

[0067] The end cap 7 and the hot-spun alloy end cap to be welded are fixedly assembled together, and then placed in a diffusion welding device to heat the end cap 7 and the hot-spun alloy end cap to be welded to the required temperature. During the heating process, pressure is gradually applied to promote the close fit between the end cap 7 and the hot-spun alloy end cap to be welded; the temperature and pressure are maintained to allow the hot-spun alloy end cap and the end cap 7 to diffuse with each other, realize welding connection, and form an anti-leakage layer; after the insulation is completed, the temperature is gradually lowered to room temperature;

[0068] The second end cap 8 and the hot-spun alloy end cap to be welded are fixedly assembled together, and then placed in a diffusion welding device to heat the second end cap 8 and the hot-spun alloy end cap to be welded to the required temperature. During the heating process, pressure is gradually applied to promote the second end cap 8 and the hot-spun alloy end cap to be welded to fit tightly together; the temperature and pressure are maintained to allow the hot-spun alloy end cap and the second end cap 8 to diffuse with each other, realize welding connection, and form an anti-leakage layer; after the insulation is completed, the temperature is gradually lowered to room temperature;

[0069] In step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 10-80%, the mass content ratio of aluminum powder is 5-30%, and the balance is zirconium oxide powder.

[0070] In step S2, the sintering temperature is 300-1100°C, the sintering time is 0.5-1 hour, and the sintering pressure is 0.1-10 MPa; in step S3, the micropore diameter of the gas micropore channel is 0.1-500 μm.

[0071] In step S4, the thickness of the transition interface is 50-500 nm, and the thickness of the oxide interface is 50-500 nm.

[0072] In step S5, the thermal diffusion treatment temperature is 200-1000° C., and the thermal diffusion treatment time is 0.5-1 hour.

[0073] In step S5, the thermal diffusion treatment temperature is 500-800°C.

[0074] In step S7, the getter uses zirconium metal as an active component and aluminum metal as a synthetic framework component, and the getter is a zirconium-aluminum 16-ring getter.

[0075] In step S9, the alkali metal working medium is sodium, potassium or lithium; in step S10, the thickness of the gas barrier coating is 0.01-0.05 mm;

[0076] In step S11, the heat treatment temperature is 600~1000℃, and the heat treatment time is 0.5~1 hour; in step S12, the thickness of the hot-spun alloy head is 0.1~0.5mm, the material of the hot-spun alloy head is nickel metal, chromium metal or iron metal, and the inner surface of the hot-spun alloy head is pre-coated with platinum metal coating, and the thickness of the platinum metal coating is 0.05~100μm.

[0077] The tailless packaged heat pipe manufactured by the tailless packaged heat pipe manufacturing process comprises a heat pipe 1, the heat pipe 1 comprises a heat pipe fitting 6, and a head 7 and a head 2 8 are respectively provided at both ends of the heat pipe fitting 6, an isolation net 4 is provided inside the heat pipe fitting 6, an anti-wetting coating is provided on the isolation net 4, an air intake chamber 3 is provided between the isolation net 4 and the head 1 7, a getter is provided in the air intake chamber 3, a working chamber 2 is provided between the isolation net 4 and the head 2 8, an alkali metal reflux net 5 is provided in the working chamber 2, a gas barrier coating is provided on the head 1 7 and the head 2 8, and an anti-leakage layer is provided outside the gas barrier coating.

[0078] Example 2

[0079] In step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 10%, the mass content ratio of aluminum powder is 5%, and the balance is zirconium oxide powder.

[0080] In step S2, the sintering temperature is 1100°C, the sintering time is 0.5 hours, and the sintering pressure is 10 MPa.

[0081] In step S3, the micropore diameter of the gas microporous channel is 0.1-50 μm, and a 30 wt.% sodium hydroxide alkaline solution is selected.

[0082] In step S4, the thickness of the transition interface is 500 nm, and the thickness of the oxide interface is 50 nm.

[0083] In step S5 , the thermal diffusion treatment temperature is 200° C., and the thermal diffusion treatment time is 1 hour.

[0084] In step S6, the isolation net 4 is welded to the inner wall of the heat pipe fitting 6 at a distance of 100 mm from one end of the heat pipe fitting 6.

[0085] In step S9, the alkali metal working medium is sodium.

[0086] In step S10, the thickness of the gas barrier coating is 0.05 mm.

[0087] In step S11, the heat treatment temperature is 700° C. and the heat treatment time is 0.8 hours.

[0088] In step S12, the thickness of the hot-spun alloy head is 0.2 mm, the hot-spun alloy head is nickel metal, and the thickness of the platinum metal coating is 10 μm.

[0089] The remaining steps and structures are the same as in Example 1.

[0090] Example 3

[0091] In step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 80%, the mass content ratio of aluminum powder is 10%, and the balance is zirconium oxide powder.

[0092] In step S2, the sintering temperature is 300°C, the sintering time is 1 hour, and the sintering pressure is 0.1 MPa.

[0093] In step S3, the micropore diameter of the gas microporous channel is 50-100 μm, and a 35 wt.% sodium hydroxide alkaline solution is selected.

[0094] In step S4, the thickness of the transition interface is 200 nm, and the thickness of the oxide interface is 500 nm.

[0095] In step S5 , the thermal diffusion treatment temperature is 500° C., and the thermal diffusion treatment time is 1 hour.

[0096] In step S6, the isolation net 4 is welded to the inner wall of the heat pipe fitting 6 at a distance of 50 mm from one end of the heat pipe fitting 6.

[0097] In step S9, the alkali metal working medium is lithium.

[0098] In step S10, the thickness of the gas barrier coating is 0.01 mm.

[0099] In step S11, the heat treatment temperature is 1000° C. and the heat treatment time is 0.5 hours.

[0100] In step S12, the thickness of the hot-spun alloy head is 0.1 mm, the hot-spun alloy head is iron metal, and the thickness of the platinum metal coating is 100 μm.

[0101] The remaining steps and structures are the same as in Example 1.

[0102] Example 4

[0103] In step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 50%, the mass content ratio of aluminum powder is 20%, and the balance is zirconium oxide powder.

[0104] In step S2, the sintering temperature is 800°C, the sintering time is 0.6 hours, and the sintering pressure is 6 MPa.

[0105] In step S3, the micropore diameter of the gas microporous channel is 100-300 μm, and a 35 wt.% potassium hydroxide alkaline solution is selected.

[0106] In step S4, the thickness of the transition interface is 100 nm, and the thickness of the oxide interface is 200 nm.

[0107] In step S5 , the thermal diffusion treatment temperature is 800° C., and the thermal diffusion treatment time is 0.7 hours.

[0108] In step S6, the isolation net 4 is welded to the inner wall of the heat pipe fitting 6 at a distance of 10 mm from one end of the heat pipe fitting 6.

[0109] In step S9, the alkali metal working medium is potassium.

[0110] In step S10, the thickness of the gas barrier coating is 0.02 mm.

[0111] In step S11, the heat treatment temperature is 800° C. and the heat treatment time is 0.6 hours.

[0112] In step S12, the thickness of the hot-spun alloy head is 0.3 mm, the hot-spun alloy head is iron metal, and the thickness of the platinum metal coating is 1 μm.

[0113] The remaining steps and structures are the same as in Example 1.

[0114] Example 5

[0115] In step S1, the mass content ratio of nickel or chromium metal powder in the mixture is 30%, the mass content ratio of aluminum powder is 30%, and the balance is zirconium oxide powder.

[0116] In step S2, the sintering temperature is 600°C, the sintering time is 0.7 hours, and the sintering pressure is 3 MPa.

[0117] In step S3, the micropore diameter of the gas microporous channel is 300-500 μm, and a 30 wt.% potassium hydroxide alkaline solution is selected.

[0118] In step S4, the thickness of the transition interface is 50 nm, and the thickness of the oxide interface is 100 nm.

[0119] In step S5 , the thermal diffusion treatment temperature is 1000° C., and the thermal diffusion treatment time is 0.5 hour.

[0120] In step S6 , the isolation net 4 is welded to the inner wall of the heat pipe fitting 6 at a distance of 80 mm from one end of the heat pipe fitting 6 .

[0121] In step S9, the alkali metal working medium is sodium.

[0122] In step S10, the thickness of the gas barrier coating is 0.03 mm.

[0123] In step S11, the heat treatment temperature is 600° C. and the heat treatment time is 1 hour.

[0124] In step S12, the thickness of the hot-spun alloy head is 0.5 mm, the hot-spun alloy head is chromium metal, and the thickness of the platinum metal coating is 0.05 μm.

[0125] The remaining steps and structures are the same as in Example 1.

[0126] The effect test is as follows:

[0127] 1. Alkali metal heat pipes are generally used in space satellite reactors, civilian waste heat recovery and other fields. The design life needs to be more than 10 years. However, the failure time of alkali metal heat pipes with tail packaging process is generally concentrated within 5 years.

[0128] The comparison results of helium mass spectrometer leak rate are as follows:

[0129] (1) After 7000 hours of operation, the alkali metal heat pipe with tail packaging process has increased from the initial 1.3×10 -10 Pam 3 / s decreased to 1.3×10 -8 Pam 3 / s accounts for more than 70%;

[0130] (2) After 7000 hours of operation, the tailless package heat pipe manufactured by the tailless package heat pipe manufacturing process in the embodiment has a heat transfer capacity of 1.3×10 -10 Pam 3 / s decreased to 1.3×10 -9 Pam 3 / s accounts for no more than 10%.

[0131] Therefore, the service life of the tailless packaged heat pipe of the present invention is greatly improved compared with the alkali metal heat pipe with a tail package process.

[0132] 2. If the isolation net 4 of the present invention is not used, the getter will come into contact with the alkali metal working medium, resulting in failure to work; if the isolation net 4 is only composed of metal, the function of gas passing cannot be achieved. The principle is to use the low wetting angle of the oxide in the microporous channel to the alkali metal working medium, so that the alkali metal working medium cannot pass through, but the gas can pass through.

[0133] After a long period of experiments, it is proved that the alkali metal working medium of the present invention cannot enter the suction chamber 3, which ensures the smooth implementation of the present invention.

[0134] If in step S1, the mass content ratio of nickel or chromium metal powder in the mixture is not within the range of 10-80%, and the mass content ratio of aluminum powder is not within the range of 5-30%, after running for 2000 hours, part of the alkali metal working medium enters the suction chamber 3, and the purpose of the present invention cannot be achieved.

[0135] If in step S4, titanium metal vapor is not vapor-deposited on the isolation net 4 and only zirconium oxide vapor is vapor-deposited, or only titanium metal vapor is vapor-deposited and zirconium oxide vapor is not vapor-deposited on the isolation net 4, or neither titanium metal vapor nor zirconium oxide vapor is vapor-deposited on the isolation net 4, the purpose of the present invention cannot be achieved.

Claims

1. A process for manufacturing a tailless packaged heat pipe, characterized in that: The following steps are involved: S1. Preparing a mixture: mixing nickel or chromium metal powder, zirconium oxide powder and aluminum powder to form a mixture, wherein the mass content ratio of the nickel or chromium metal powder in the mixture is 10-80%, the mass content ratio of the aluminum powder is 5-30%, and the balance is zirconium oxide powder; S2. Sintering: placing the mixture in a mesh mold, and sintering the mixture under vacuum or inert gas protection conditions to form a separator, the sintering temperature is 300-1100°C, the sintering time is 0.5-1 hour, and the sintering pressure is 0.1-10MPa; S3, pore forming treatment: after the isolation plate is cooled, the isolation plate is immersed in an alkaline solution of sodium hydroxide or potassium hydroxide to remove aluminum powder in the isolation plate, so that the isolation plate forms an isolation net (4) with gas microporous channels, and the micropore diameter of the gas microporous channels is 0.1-500 μm; S4, making an anti-wetting coating: vapor-depositing titanium metal vapor on the isolation net (4), the titanium metal adsorbing and diffusing on the surface of the isolation net (4) to form a transition interface, and then vapor-depositing zirconium oxide vapor, the zirconium oxide and the titanium metal combining to form an oxide interface, the transition interface respectively connecting the isolation net (4) and the oxide interface; S5, thermal diffusion: placing the isolation net (4) in a heat treatment furnace, and performing a thermal diffusion treatment on the isolation net (4) under vacuum or inert gas protection conditions, wherein the thermal diffusion treatment temperature is 200-1000° C., the thermal diffusion treatment time is 0.5-1 hour, and the thermal diffusion treatment temperature is 500-800° C.; S6. Welding the isolation net (4): welding the isolation net (4) to the inner wall of the heat pipe fitting (6) at a distance of 10 to 100 mm from one end of the heat pipe fitting (6); the isolation net (4) and one end of the heat pipe fitting (6) form an air suction chamber (3); the isolation net (4) and the other end of the heat pipe fitting (6) form a working chamber (2); the length of the working chamber (2) is greater than the length of the air suction chamber (3); S7, setting a getter: setting the getter in the getter chamber (3); S8, preparing a sealing head (7): under vacuum conditions, vacuum hot spinning and sealing an end of the heat pipe fitting (6) close to the suction chamber (3) to form a sealing head (7); S9, preparing the second end cap (8): fixing the alkali metal reflux net (5) in the working chamber (2), filling the working chamber (2) with an alkali metal working medium, and vacuum hot spinning and sealing the end of the heat pipe fitting (6) away from the suction chamber (3) to form the second end cap (8); S10, manufacturing a gas barrier coating: platinum metal is plated on the surface of the first end cap (7) and the second end cap (8) to form a gas barrier coating; S11, heat treatment: placing the first end cap (7) and the second end cap (8) in a heat treatment furnace, and heat treating the first end cap (7) and the second end cap (8) under vacuum or inert gas protection conditions, wherein the heat treatment temperature is 600-1000°C and the heat treatment time is 0.5-1 hour; S12. Making an anti-leakage layer: diffusion welding a hot-spun alloy head on the surface of the head 1 (7) and the head 2 (8) to form an anti-leakage layer, the thickness of the hot-spun alloy head is 0.1-0.5 mm, the material of the hot-spun alloy head is nickel metal, chromium metal or iron metal, and the inner surface of the hot-spun alloy head is pre-plated with a platinum metal coating, and the thickness of the platinum metal coating is 0.05-100 μm.

2. The process for manufacturing a tailless packaged heat pipe according to claim 1, characterized in that: In step S4, the thickness of the transition interface is 50-500 nm, and the thickness of the oxide interface is 50-500 nm.

3. The process for manufacturing a tailless packaged heat pipe according to claim 1, characterized in that: In step S7, the getter uses zirconium metal as an active component and aluminum metal as a synthetic framework component, and the getter is a zirconium-aluminum 16-ring getter.

4. The process for manufacturing a tailless packaged heat pipe according to claim 1, characterized in that: In step S9, the alkali metal working medium is sodium, potassium or lithium.

5. The process for manufacturing a tailless packaged heat pipe according to claim 1, characterized in that: In step S10, the thickness of the gas barrier coating is 0.01-0.05 mm.

6. A tailless packaged heat pipe manufactured by the tailless packaged heat pipe manufacturing process according to any one of claims 1 to 5, characterized in that: The invention comprises a heat pipe (1), wherein the heat pipe (1) comprises a heat pipe fitting (6), a first end cap (7) and a second end cap (8) are respectively arranged at both ends of the heat pipe fitting (6), an isolation net (4) is arranged inside the heat pipe fitting (6), an anti-wetting coating is arranged on the isolation net (4), an air suction chamber (3) is arranged between the isolation net (4) and the first end cap (7), an air suction agent is arranged in the air suction chamber (3), a working chamber (2) is arranged between the isolation net (4) and the second end cap (8), an alkali metal reflux net (5) is arranged in the working chamber (2), a gas barrier coating is arranged on the first end cap (7) and the second end cap (8), and an anti-leakage layer is arranged outside the gas barrier coating.

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