Power transfer window for traveling wave tube and its fabrication method

Abstract

This invention provides a power transmission window for a traveling wave tube and its fabrication method, belonging to the field of electronic vacuum device technology. The power transmission window includes an outer conductor, an inner conductor, and a window ceramic. The outer conductor is configured as a coaxial annular composite structure, including a first annular portion and a second annular portion. The second annular portion is brazed within the first annular portion. The first annular portion is made of a molybdenum-copper alloy, and the second annular portion is made of oxygen-free copper. The inner conductor is formed by brazing a power transmission needle and a power transmission needle sealing body. The inner conductor axially penetrates the outer conductor from the power transmission needle side, and the power transmission needle sealing body is a hollow structure. The window ceramic passes through the power transmission needle sealing body and is brazed perpendicularly to it, with the outer circumference of the window ceramic brazed to the inner side of the second annular portion.

Description

Technical Field

[0001] This invention relates to the field of vacuum electronic devices, and in particular to a power transmission window for a traveling wave tube and its fabrication method. Background Technology

[0002] A space traveling wave tube is a microwave vacuum electronic device that amplifies signals by utilizing the interaction between an electron beam and electromagnetic waves. It is a core component of satellites and features high efficiency, high frequency band, and long lifespan. It is currently a core component of systems such as large-capacity communication, high-power space attack and defense, high-resolution radar, and deep space exploration.

[0003] A traveling wave tube (TWT) exchanges energy with a traveling microwave field through electrons, amplifying the microwave signal before outputting it through a power window. Therefore, the power window of a TWT directly affects its degassing, high-frequency loss, bandwidth, and output power stability.

[0004] Traditional power transmission windows generally adopt a coaxial structure with Kovar alloy as the outer conductor and molybdenum as the inner conductor. Due to the high sealing stress between the inner conductor and the window ceramic pin, poor thermal matching, and insufficient heat dissipation capacity of Kovar alloy, the local temperature is too high, which directly affects the airtightness of the window ceramic and metal seal, resistance to temperature shock and mechanical vibration, and it is difficult to meet the reliability requirements of L-Ku band power ≥1000W space traveling wave tubes. Summary of the Invention

[0005] In view of this, in order to at least partially solve at least one of the aforementioned technical problems, the present invention provides a power transmission window for a traveling wave tube and a method for its fabrication.

[0006] According to one aspect of the present invention, a power transmission window for a traveling wave tube is provided, comprising an outer conductor, an inner conductor, and a window ceramic, wherein the outer conductor is configured as a coaxial annular composite structure, comprising a first annular portion and a second annular portion, the second annular portion being brazed within the first annular portion, the first annular portion being made of a molybdenum-copper alloy, and the second annular portion being made of oxygen-free copper; the inner conductor is formed by brazing a power transmission needle and a power transmission needle sealing body, the inner conductor axially penetrating the outer conductor from the power transmission needle side, and the power transmission needle sealing body being a hollow structure; the window ceramic is brazed through the power transmission needle sealing body and perpendicularly brazed to the power transmission needle sealing body, and the outer circumference of the window ceramic is brazed to the inner side of the second annular portion.

[0007] According to an embodiment of the present invention, the first annular portion and the second annular portion are in a clearance fit, and the clearance is less than 0.06~0.08.

[0008] According to an embodiment of the present invention, the thickness of the first annular portion is 1-3 mm, the thickness of the second annular portion is less than or equal to 1 mm, and the thickness of the hollow structure of the energy delivery needle sealing body is 0.2-0.3 mm.

[0009] According to an embodiment of the present invention, the coefficient of thermal expansion of the material used in the first annular portion matches the coefficient of thermal expansion of the material used in the window ceramic.

[0010] According to an embodiment of the present invention, the diameter of the first port of the first annular portion is greater than the diameter of the second port of the first annular portion; the diameter of the third port of the second annular portion is greater than the diameter of the fourth port of the second annular portion.

[0011] According to another aspect of the present invention, a method for preparing an energy transfer window is provided, characterized in that it includes:

[0012] An outer conductor is prepared using a first brazing mold and then machined to obtain a machined outer conductor. The machined outer conductor is a coaxial annular composite structure, including a first annular portion and a second annular portion. A second brazing mold and a third brazing mold are provided, and the third brazing mold is assembled into the second brazing mold to form a brazing mold assembly. The outer conductor is assembled inside the third brazing mold of the brazing mold assembly. The energy transmission needle, the energy transmission needle sealing body, and the window ceramic are assembled together, placed inside the outer conductor, and welded in a hydrogen furnace to form an energy transmission window.

[0013] According to an embodiment of the present invention, the preparation of an outer conductor using a first brazing mold includes: pre-treating a blank of a first annular portion and a blank of a second annular portion; placing the blank of the first annular portion inside the first brazing mold; and assembling the blank of the second annular portion inside the blank of the first annular portion to form a blank of an annular composite structure, wherein the material of the blank of the first annular portion is a molybdenum-copper alloy, and the material of the blank of the second annular portion is oxygen-free copper; placing a pressure block on the upper part of the blank of the annular composite structure and welding it in a hydrogen furnace to form an outer conductor.

[0014] According to an embodiment of the present invention, pretreatment of the blanks of the first annular portion and the second annular portion includes: cleaning the blanks of the first annular portion and the second annular portion respectively; and applying silver plating to the outer surface of the cleaned blank of the second annular portion.

[0015] According to an embodiment of the present invention, the welding temperature in the hydrogen furnace is 800°C, and the vacuum degree is less than or equal to 5 × 10⁻⁶. - 3 Pa.

[0016] According to an embodiment of the present invention, the method further includes: placing solder at the connection between the power supply needle and the power supply needle sealing body, and placing solder at the connection between the window ceramic and the power supply needle sealing body.

[0017] According to an embodiment of the present invention, the outer conductor, which is composed of a first annular portion made of molybdenum-copper alloy and a second annular portion made of oxygen-free copper, forms a coaxial annular composite structure. Since the thermal conductivity of the composite material of oxygen-free copper and molybdenum-copper alloy is significantly higher than that of the single Kovar alloy of the traditional power transmission window outer conductor, it can both meet the requirement of matching the thermal expansion coefficient with ceramics and reduce the microwave output loss of the power transmission window, while also improving the thermal conductivity of the power transmission window. In addition, the power transmission needle sealing body in the inner conductor adopts a hollow structure, which can reduce the sealing stress of the power transmission window during thermal changes and improve the reliability of the power transmission window structure. Attached Figure Description

[0018] The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments of the invention with reference to the accompanying drawings, in which:

[0019] Figure 1 This is a schematic diagram of the energy transmission window according to an embodiment of the present invention;

[0020] Figure 2 This is a flowchart of a method for preparing an energy transfer window according to an embodiment of the present invention;

[0021] Figure 3(a) is a schematic diagram of the preparation of the outer conductor according to an embodiment of the present invention;

[0022] Figure 3(b) is a schematic diagram of the prepared and processed outer conductor;

[0023] Figure 4 This is a schematic diagram of the assembly of the energy transmission window according to an embodiment of the present invention. Detailed Implementation

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "comprising" as used herein indicates the presence of features, steps, or operations, but does not exclude the presence or addition of one or more other features.

[0026] When using expressions such as "at least one of A, B, and C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). When using expressions such as "at least one of A, B, or C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0027] The microwave transmission structure using a high-power, wide-bandwidth space traveling wave tube employs a highly reliable sealed coaxial window. The structural feature is that the window ceramic, the outer conductor of the power transmission window, and the inner conductor are all sealed with high reliability, ensuring that the space traveling wave tube can achieve high-power output under high vacuum.

[0028] In related technologies, one structure of the outer conductor of the power transmission window uses a single material, such as Kovar or tungsten copper. Due to the poor thermal conductivity of Kovar (around 20 W / (m·K)) and the high thermal conductivity of tungsten copper (around 220 W / (m·K)), the high electrical conductivity results in high high-frequency losses. As the temperature rises, the expansion coefficients of tungsten copper and Kovar are much higher than those of ceramics. Because there is no structure to release expansion stress, thermal expansion causes structural mismatch, resulting in air leakage at the weld and failure of the traveling wave tube. Another structure uses a thin-walled component for the outer conductor of the power transmission window, mainly using Kovar 4J33 and 4J34. The main disadvantages are: first, the narrow heat dissipation path leads to excessively high temperature and increased high-frequency losses, which is not conducive to the high-power transmission of the traveling wave tube; second, the structural strength is poor, and when the power transmission window is subjected to external force, the sealing surface is easily stressed, causing air leakage and failure of the traveling wave tube.

[0029] Due to bandwidth requirements, the window ceramic and inner conductor adopt a needle-sealed structure, which is difficult to seal. Because the needle has good rigidity, the ceramic is under tensile stress during contraction and expansion, which can easily cause air leakage at the seal between the ceramic and the inner conductor, resulting in low reliability and making it unsuitable for applications of space traveling wave tubes with power ≥1000W.

[0030] In view of this, the present invention proposes a power transmission window for traveling wave tubes, which enables the outer conductor composite structure of the power transmission window to reduce microwave output loss while improving the thermal conductivity of the power transmission window, and also makes the ceramic and sealing joint highly reliable, so that the power transmission window is applicable to space traveling wave tubes with power ≥1000W.

[0031] Figure 1 This is a schematic diagram of the energy transmission window according to an embodiment of the present invention.

[0032] like Figure 1 As shown, the power transmission window can be used in a space traveling wave tube. The power transmission window includes an outer conductor 1, an inner conductor 2, and a window ceramic 3.

[0033] According to an embodiment of the present invention, the outer conductor 1 can be configured as a coaxial annular composite structure, including a first annular portion 1-1 and a second annular portion 1-2. The second annular portion 1-2 is brazed to the inside of the first annular portion 1-1. The first annular portion 1-1 can be made of a molybdenum-copper alloy, and the second annular portion 1-2 can be made of oxygen-free copper.

[0034] According to an embodiment of the present invention, the first annular portion 1-1 may also be made of a material with high structural strength, moderate thermal conductivity and matching coefficient of ceramic expansion. For example, in addition to molybdenum-copper alloy, tungsten-copper alloy, molybdenum alloy, etc. may also be used.

[0035] According to an embodiment of the present invention, the first annular portion 1-1 of the outer conductor is made of a high thermal conductivity material that matches the coefficient of thermal expansion of ceramics, and the second annular portion 1-2 is made of oxygen-free copper material to form an annular composite structure. Since the thermal conductivity of both is higher than that of traditional Kovar alloy, the outer conductor with an annular composite structure can improve the thermal conductivity and heat dissipation capacity of the energy transmission window.

[0036] According to an embodiment of the present invention, the inner conductor 2 is formed by brazing an energy-transmitting needle 2-1 and an energy-transmitting needle sealing body 2-2. The inner conductor 2 is axially inserted into the outer conductor 1 from one side of the energy-transmitting needle 2-1.

[0037] According to an embodiment of the present invention, the energy transmission needle 2-1 is a solid needle-shaped structure, and the energy transmission needle sealing body 2-2 is a hollow structure. The energy transmission needle 2-1 and the energy transmission needle sealing body 2-2 can be connected by brazing to form an inner conductor.

[0038] According to an embodiment of the present invention, the energy transmission needle sealing body 2-2 in the inner conductor 2 adopts a hollow structure, the purpose of which is to reduce sealing stress and improve the reliability of the welding structure between the inner conductor and the window porcelain needle seam.

[0039] According to an embodiment of the present invention, the window ceramic 3 can be brazed perpendicularly to the energy transmission needle sealing body 2-2, the outer circumference of the window ceramic 3 is brazed to the inner side of the second annular portion 1-2 of the outer conductor, and the inner hole side of the window ceramic 3 is brazed to a section of the outer circumference of the energy transmission needle sealing body 2-2.

[0040] According to an embodiment of the present invention, the first annular portion 1-1 and the second annular portion 1-2 in the outer conductor 1 are fitted with a gap, the gap being less than 0.06 to 0.08. This is intended to facilitate processing during the fabrication of the outer conductor by utilizing the gap between the first and second annular portions.

[0041] According to an embodiment of the present invention, the coefficient of thermal expansion of the material used in the first annular portion 1-1 is matched with the coefficient of thermal expansion of the material used in the window ceramic 3, so that the annular composite structure can modulate the coefficient of thermal expansion and match the expansion of the window ceramic. The selected oxygen-free copper and molybdenum copper alloys are non-magnetic, which can optimize the microwave output performance of the power transmission window.

[0042] According to an embodiment of the present invention, the diameter of the first port a of the first annular portion 1-1 in the outer conductor 1 is greater than the diameter of the second port b of the first annular portion 1-1; similarly, the diameter of the third port c of the second annular portion 1-2 brazed inside the first annular portion 1-1 is greater than the diameter of the fourth port b of the second annular portion 1-2.

[0043] According to an embodiment of the present invention, the thickness of the first annular portion 1-1 in the outer conductor 1 is 1~3mm, which is selected based on three factors: the design size of the energy transmission window, the structural strength of the outer conductor, and the thermal conductivity volume. In actual use, the thickness can be appropriately increased according to actual needs.

[0044] According to an embodiment of the present invention, the thickness of the second annular portion 1-2 in the outer conductor 1 is ≤1mm, preferably 0.3~0.8mm, so that the outer conductor has a suitable sealing stress and the loss of the power transmission window is reduced.

[0045] According to an embodiment of the present invention, the second annular portion of the outer conductor is made of oxygen-free copper, which has the highest thermal conductivity and low yield strength, to ensure sealing reliability and optimal heat dissipation near the window ceramic. The first annular portion of the outer conductor is made of materials such as molybdenum copper, tungsten copper, molybdenum, and tungsten, which have good thermal conductivity, expansion coefficient matching the window ceramic, and high yield strength to achieve heat dissipation. This ensures that the composite structure of the outer conductor of the energy transmission window has good external heat dissipation and structural strength.

[0046] According to an embodiment of the present invention, the energy transmission needle sealing body 2-2 in the inner conductor 2 is a hollow structure with a thickness of 0.2-0.3 mm. This is designed considering the structural strength of the metal material, the processing size that can achieve vacuum tightness, and the microwave transmission path, so that the sealing stress can be better released by the plastic deformation of the inner conductor when the inner conductor undergoes thermal changes. This allows the internal stress caused by thermal expansion and other reasons to be lower than the tensile strength of the ceramic and the weld, thereby obtaining an energy transmission window with a highly reliable structure.

[0047] According to an embodiment of the present invention, the inner conductor is made of oxygen-free copper or molybdenum, which has the highest thermal conductivity, and adopts a hollow structure to ensure the reliability of the welding between the inner conductor and the window ceramic.

[0048] Figure 2 This is a flowchart of a method for preparing an energy transfer window according to an embodiment of the present invention.

[0049] like Figure 2 As shown, the method may include operations S210 to S240.

[0050] In operation S210, an outer conductor is prepared using a first brazing mold and then machined to obtain a machined outer conductor. The machined outer conductor is a coaxial ring-shaped composite structure, including a first ring-shaped portion and a second ring-shaped portion.

[0051] In operation S220, a second brazing mold and a third brazing mold are provided, and the third brazing mold is assembled into the second brazing mold to form a brazing mold assembly.

[0052] In operation S230, the outer conductor is assembled into the third brazing mold of the brazing mold assembly.

[0053] In operation S240, the energy transmission needle, energy transmission needle sealing body and window ceramic are assembled together, placed inside the outer conductor, and welded in a hydrogen furnace to form the energy transmission window.

[0054] According to an embodiment of the present invention, the preparation of an outer conductor using a first brazing mold may include: pre-treating a blank of a first annular portion and a blank of a second annular portion, placing the blank of the first annular portion inside the first brazing mold, and assembling the blank of the second annular portion inside the blank of the first annular portion, wherein the material of the blank of the first annular portion is a molybdenum-copper alloy, and the material of the blank of the second annular portion is oxygen-free copper; placing a pressure block on the upper part of the blank of the second annular portion and welding it in a hydrogen furnace to form an outer conductor with an annular composite structure.

[0055] According to an embodiment of the present invention, the blank of the first annular portion can be a blank of molybdenum-copper alloy, and the blank of the second annular portion can be a blank of oxygen-free copper.

[0056] According to an embodiment of the present invention, pre-processing the blanks of the first annular portion and the second annular portion may include: cleaning the blanks of the first annular portion and the second annular portion respectively; and applying silver plating to the outer surface of the cleaned blank of the second annular portion respectively.

[0057] According to an embodiment of the present invention, the blanks of the first annular portion and the second annular portion can be cleaned and set aside for later use, and then the outer surface of the blank of the second annular portion can be silver-plated.

[0058] According to embodiments of the present invention, silver plating on the outer surface can be performed by electroplating, magnetron sputtering, or other methods, and this application does not specifically limit the method.

[0059] According to an embodiment of the present invention, two blanks are processed for the outer conductor 2. The inner blank, i.e., the blank of the second annular portion, is made of oxygen-free copper material, and its outer surface must meet a certain surface roughness, for example, the surface roughness can be better than 0.08. The outer blank, i.e., the blank of the first annular portion, is made of molybdenum-copper alloy, and its inner surface must meet a certain surface roughness, for example, the surface roughness can be better than 0.08. Then, the outer surface of the blank of the second annular portion is silver-plated. The circumferential clearance between the two blanks is controlled within (0.3-0.6)D×10. -2 Within this range, where D is the diameter of the oxygen-free copper blank, the two blanks are welded together, with the welding temperature controlled between 780-800℃. The composite blank is then machined to form the outer conductor of the power transmission window.

[0060] Figure 3(a) is a schematic diagram of the preparation of the outer conductor according to an embodiment of the present invention; Figure 3(b) is a schematic diagram of the prepared and processed outer conductor.

[0061] As shown in Figure 3(a), the blank of the first annular portion 1-1 can be placed inside the first brazing mold 4, and the blank of the second annular portion 1-2 can be assembled inside the blank of the first annular portion 1-1. A pressure block 5 is then placed on top of the blank of the second annular portion 1-2. The pressure block 5 holds the first brazing mold 4 and the blanks of the first and second annular portions 1-1 inside the first brazing mold 4, and places them in a hydrogen furnace or vacuum furnace at a temperature of 800℃ with a vacuum degree better than 5×10⁻⁶. -3 Pa, after heat preservation for 10 minutes. Remove the pressure block 5 and the first brazing mold 4 to obtain a blank of the outer conductor with a ring-shaped composite structure. Machining the blank of the outer conductor with a ring-shaped composite structure can yield an outer conductor with a ring-shaped composite structure (as shown in Figure 3(b)).

[0062] Figure 4 This is a schematic diagram of the assembly of the energy transmission window according to an embodiment of the present invention.

[0063] like Figure 4As shown, the second brazing mold 6 and the third brazing mold 7 are assembled together, specifically, the third brazing mold 7 is assembled into the second brazing mold 6 to form a brazing mold assembly; then the outer conductor 1 is assembled into the third brazing mold 7 of the brazing mold assembly, and the energy transmission needle 2-1 in the inner conductor 2 passes through the outer conductor 1, with the energy transmission needle sealing body 2-2 in the inner conductor placed above the energy transmission needle 2-1, and solder 8 placed between the energy transmission needle 2-1 and the energy transmission needle sealing body 2-2; the outer surface of the window ceramic 3... The inner side of the second annular portion of the outer conductor 1 is brazed to the circumference of the window ceramic 3, and a section of the outer circle of the energy transmission needle sealing body 2-2 is brazed to the inner hole of the window ceramic 3. A ceramic gasket 9 is placed at a certain position on the window ceramic 3, and solder 10 is placed at the position where the inner hole of the window ceramic 3 contacts the energy transmission needle sealing body 2-2. Solder 11 is placed at the position where the outer circumference of the window ceramic 3 contacts the second annular portion of the outer conductor 1. The fourth brazing mold 12 is assembled on top of the window ceramic 3 to form the assembled energy transmission window component.

[0064] According to an embodiment of the present invention, the assembled energy transmission window components are placed in a hydrogen furnace for brazing. The brazing temperature can be 1000℃±20℃, using a gradual heating curve. The heating rate at the high temperature stage is no more than 20℃ / min, and the temperature is held for 3 minutes. Then, the temperature is lowered, and all brazing molds and components such as gaskets are removed to form the energy transmission window structure. Figure 1 As shown.

[0065] According to embodiments of the present invention, due to the increased requirements for vacuum and high-voltage insulation in high-power space traveling wave tubes, ultra-vacuum conditions are required. Therefore, a low-vacuum-pressure gold-based solder is used to achieve highly reliable sealing brazing of the outer conductor, window ceramic, and inner conductor of the power transmission window. This method ensures that high-voltage insulation is not affected even under high-temperature baking and degassing conditions. Furthermore, because gold-copper solder has high yield strength and poor flowability, the weld surface condition, weld structure, and welding parameters are crucial to the weld quality.

[0066] According to an embodiment of the present invention, the weld gap can be selected as 0.06-0.08 mm, and a chamfer is required for flow guidance. Welding is performed using a plug for positioning, the amount of solder is 1.5 times the gap, and 0.3 mm diameter AuCu50 solder wire is used. The heating rate is less than 20°C / min, the maximum temperature is 1000°C, the holding time is 3 min, and the temperature is lowered to 500°C at a rate less than 10°C / min. After the temperature drops below 500°C, the solder is cooled with the furnace. Stress is generated during cooling; therefore, a slow cooling method ensures the slow release of welding stress. When the temperature drops from 410°C to 240°C, AuCu50 easily undergoes an ordered transformation to form three brittle compounds: AuCu3, Au3Cu, and AuCu. Therefore, rapid gas circulation cooling with the furnace prevents the ordered transformation of the AuCu50 solder.

[0067] According to an embodiment of the present invention, the leakage rate of the formed energy transmission window can be detected, and the leakage rate is generally better than 1.0 x 10⁻⁶. -11 Pa·m 3 / s, the standing wave ratio of the slow wave component is less than 1.5.

[0068] According to an embodiment of the present invention, the outer conductor, which is composed of a first annular portion made of molybdenum-copper alloy and a second annular portion made of oxygen-free copper, forms a coaxial annular composite structure. Since the thermal conductivity of the composite material of oxygen-free copper and molybdenum-copper alloy is significantly higher than that of the single Kovar alloy of the traditional power transmission window outer conductor, it can both meet the requirement of matching the thermal expansion coefficient with ceramics and reduce the microwave output loss of the power transmission window, while also improving the thermal conductivity of the power transmission window. In addition, the power transmission needle sealing body in the inner conductor adopts a hollow structure, which can reduce the sealing stress of the power transmission window during thermal changes and improve the reliability of the power transmission window structure.

[0069] It should be noted that the terms "first," "second," "third," and "fourth" used in this invention are merely for distinction and have no practical meaning. The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this invention. It should be understood that the above are merely specific embodiments of this invention and are not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A power transmission window for a traveling wave tube, comprising an outer conductor, an inner conductor, and a window ceramic, characterized in that: The outer conductor (1) is configured as a coaxial ring-shaped composite structure, including a first ring-shaped part (1-1) and a second ring-shaped part (1-2). The second ring-shaped part (1-2) is brazed into the first ring-shaped part (1-1). The first ring-shaped part (1-1) is made of molybdenum-copper alloy, and the second ring-shaped part (1-2) is made of oxygen-free copper. The first ring-shaped part (1-1) and the second ring-shaped part (1-2) are in clearance fit, and the fit gap is less than 0.06mm~0.08mm. The inner conductor (2) is brazed from the energy transmission needle (2-1) and the energy transmission needle sealing body (2-2). The inner conductor passes through the outer conductor (1) axially from the side of the energy transmission needle (2-1). The energy transmission needle sealing body (2-2) is a hollow structure. The window ceramic (3) is brazed perpendicularly to the energy transmission needle sealing body (2-2) through the energy transmission needle sealing body (2-2), and the outer circumference of the window ceramic (3) is brazed to the inner side of the second annular part (1-2).

2. The energy transmission window according to claim 1, characterized in that, The thickness of the first annular portion (1-1) is 1-3 mm, the thickness of the second annular portion (1-2) is less than or equal to 1 mm, and the thickness of the hollow structure of the energy transmission needle sealing body (2-2) is 0.2-0.3 mm.

3. The energy transmission window according to claim 1, characterized in that, The coefficient of thermal expansion of the material used in the first annular portion (1-1) matches that of the material used in the window ceramic (3).

4. The energy transmission window according to claim 1, characterized in that, The diameter of the first port (a) of the first annular portion (1-1) is greater than the diameter of the second end (b) of the first annular portion (1-1); the diameter of the third port (c) of the second annular portion (1-2) is greater than the diameter of the fourth port (d) of the second annular portion (1-2).

5. A method for preparing an energy transfer window as described in any one of claims 1 to 4, characterized in that, include: An outer conductor is prepared using a first brazing mold (4), and the outer conductor is machined to obtain a machined outer conductor (1). The machined outer conductor is a coaxial ring-shaped composite structure, including a first ring-shaped part (1-1) and a second ring-shaped part (1-2). A second brazing mold (6) and a third brazing mold (7) are provided, and the third brazing mold (7) is assembled into the second brazing mold (6) to form a brazing mold assembly; The outer conductor (1) is assembled into the third brazing mold (7) of the brazing mold assembly; The energy transmission needle (2-1), the energy transmission needle sealing body (2-2), and the window ceramic (3) are assembled together and placed inside the outer conductor (1), and then welded in a hydrogen furnace to form an energy transmission window.

6. The method according to claim 5, characterized in that, The preparation of the outer conductor using the first brazing mold (4) includes: After pre-processing the blanks of the first annular part (1-1) and the second annular part (1-2), the blank of the first annular part (1-1) is placed inside the first brazing mold (4), and the blank of the second annular part (1-2) is assembled inside the blank of the first annular part (1-1). The material of the blank of the first annular part (1-1) is molybdenum-copper alloy, and the material of the blank of the second annular part (1-2) is oxygen-free copper. A pressure block (5) is placed on the upper part of the blank of the second annular part (1-2) and welded in the hydrogen furnace to form an outer conductor (1) with an annular composite structure.

7. The method according to claim 6, characterized in that, The pretreatment of the blanks for the first annular portion (1-1) and the second annular portion (1-2) includes: The blanks of the first annular portion (1-1) and the second annular portion (1-2) are cleaned respectively; The outer surface of the blank of the second annular part (1-2) after cleaning is silvered.

8. The method according to claim 6, characterized in that, The welding temperature in the hydrogen furnace is 800℃, and the vacuum degree is less than or equal to 5×10⁻⁶. -3 Pa.

9. The method according to claim 5, further comprising: Solder is placed at the connection between the power supply needle (2-1) and the power supply needle sealing body (2-2), and solder is also placed at the connection between the window ceramic (3) and the power supply needle sealing body (2-2).

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