Method for integrated manufacturing of folded waveguide slow wave assembly and folded waveguide slow wave assembly

Abstract

The application provides an integrated manufacturing method of a folded waveguide slow wave assembly and the folded waveguide slow wave assembly, and can be applied to the technical field of vacuum tube electronic devices. The method comprises the following steps: cutting a groove structure on the surface of a folded waveguide blank along the center line position; forming pin positioning holes on both sides of the groove structure of the folded waveguide blank; assembling two folded waveguide blanks so that the two folded waveguide blanks are aligned according to the pin positioning holes, and the groove structures of the two folded waveguide blanks are aligned to form a wire passing hole, thereby obtaining an assembled folded waveguide blank; diffusion welding the contact surface of the assembled folded waveguide blank, thereby obtaining a blank welding assembly; reaming the inner wall of the wire passing hole on the blank welding assembly, thereby forming a target electron beam channel; cutting the outer surface of the blank welding assembly corresponding to the target electron beam channel, thereby forming a target signal transmission channel; and welding the blank welding assembly and a cover plate, thereby forming a folded waveguide slow wave assembly.

Description

Technical Field

[0001] This invention relates to the field of vacuum tube electronic device technology, and in particular to an integrated manufacturing method for a folded waveguide slow wave assembly and the folded waveguide slow wave assembly itself. Background Technology

[0002] Traveling wave tubes (TWTs) are indispensable in applications such as radar, satellite communications, and electronic warfare systems. Compared to TWTs in other bands, terahertz TWTs offer advantages such as wider bandwidth, lower noise, and higher power. Among these, the metallic folded waveguide structure has become the preferred slow-wave structure for terahertz TWTs. Compared to the traditional helical slow-wave line structure, the entire slow-wave line of the folded waveguide is made of metal, resulting in a robust structure with superior heat dissipation. Furthermore, the folded waveguide exhibits significantly lower high-frequency losses than the helical waveguide. Therefore, the folded waveguide slow-wave structure not only solves the problems of heat dissipation difficulties and low power capacity but also provides a wider bandwidth and higher data transmission rate.

[0003] Currently, in order to realize the manufacturing process of folded waveguide slow wave components in terahertz traveling wave tubes, the main method is to use two independent high-speed milling and pin-aligned laser welding. However, since the blank is first milled at high speed to obtain two folded waveguides, and then pin-aligned laser welding is performed, this method of processing first and then splicing has problems such as low alignment accuracy and misalignment of electron beam channels. This results in non-uniform disturbances in the high-frequency field of interaction at the electron beam channels, affecting the continuity of the electric field distribution. Summary of the Invention

[0004] In view of this, the present disclosure provides an integrated manufacturing method for a folded waveguide slow wave assembly and the folded waveguide slow wave assembly itself.

[0005] According to one aspect of this disclosure, an integrated manufacturing method for a folded waveguide slow-wave assembly is provided, comprising: cutting a groove structure along a centerline on the surface of a folded waveguide blank; forming pin positioning holes on both sides of the groove structure of the folded waveguide blank; assembling two folded waveguide blanks such that the two folded waveguide blanks are aligned according to the pin positioning holes, and the groove structures of the two folded waveguide blanks are aligned to form wire-passing holes, thereby obtaining an assembled folded waveguide blank; performing diffusion welding on the assembled folded waveguide blank to obtain a blank welding assembly; enlarging the inner wall of the wire-passing holes on the blank welding assembly to form a target electron beam channel; cutting the outer surface of the blank welding assembly corresponding to the target electron beam channel, penetrating the blank welding assembly to form a target signal transmission channel; and welding the blank welding assembly having the target electron beam channel and the target signal transmission channel to a cover plate to form a folded waveguide slow-wave assembly.

[0006] According to an embodiment of this disclosure, the cross-section of the groove structure is semi-circular; forming pin positioning holes on both sides of the groove structure of the folded waveguide blank includes: determining positioning points on the surfaces of the two folded waveguide blanks where the pin positioning holes need to be positioned, wherein the positioning points are located on both sides of the two ends of the groove structure; and machining pin positioning holes that match the pin size according to the positions of the positioning points.

[0007] According to an embodiment of this disclosure, assembling two folded waveguide blanks such that the two folded waveguide blanks are aligned with the pin positioning holes and the groove structures of the two folded waveguide blanks are spliced ​​together to form a wire-passing hole, to obtain the assembled folded waveguide blank, includes: inserting one end of a pin into the pin positioning hole of one of the folded waveguide blanks; aligning and fixing the pin positioning hole of the other folded waveguide blank with the other end of the pin, so that the groove structures of the two folded waveguide blanks are spliced ​​together to form a wire-passing hole, thus forming the assembled folded waveguide blank.

[0008] According to an embodiment of this disclosure, the above-mentioned diffusion welding of the contact surfaces of the assembled folded waveguide blank to obtain a blank welding assembly includes: placing the assembled folded waveguide blank in a diffusion welding device, and reinforcing the assembled folded waveguide blank with a fixture in a cold state; heating the fixed assembled folded waveguide blank; and applying pressure diffusion welding to the heated folded waveguide blank with the upper pressure head of the diffusion welding device to obtain the blank welding assembly.

[0009] According to embodiments of this disclosure, the above-mentioned diffusion welding conditions include: diffusion welding temperature, holding time, diffusion welding pressure, and diffusion welding displacement; the above-mentioned diffusion welding temperature includes [940, 960] °C; the above-mentioned holding time includes [110, 130] minutes; the above-mentioned diffusion welding pressure includes [0.2, 0.3] MPa; and the above-mentioned diffusion welding displacement includes [0.01, 0.03] mm.

[0010] According to an embodiment of this disclosure, before cutting the groove structure along the centerline on the surface of the folded waveguide blank, the method further includes: grinding the surface of the folded waveguide blank using a grinding machine to obtain two folded waveguide blanks with identical shapes and sizes.

[0011] According to embodiments of this disclosure, the signal transmission channel described above includes a serpentine channel.

[0012] According to an embodiment of this disclosure, the above-mentioned welding of the blank welding assembly having the target electron beam channel and the target signal transmission channel to the cover plate to obtain a folded waveguide slow wave structure includes: covering the cover plate to the outer surface of the target signal transmission channel; welding the contact surface between the cover plate and the outer surface of the target signal transmission channel to obtain the folded waveguide slow wave structure.

[0013] According to embodiments of this disclosure, laser welding is used as the welding method.

[0014] Another aspect of this disclosure provides a folded waveguide slow wave assembly, which is obtained according to any of the integrated manufacturing methods of the folded waveguide slow wave assembly described above.

[0015] The embodiments of this disclosure propose an integrated manufacturing method for folded slow-wave components. Two folded waveguide blanks are first aligned and diffused welded according to the pin positioning holes and wire threading holes. Then, the target signal transmission channel and target electron beam channel of the blank welding assembly are integratedly processed. This avoids the channel misalignment problem that occurs when the two blanks are aligned with pins after the channels are processed, as well as the disturbance problem of non-uniform high-frequency field of interaction caused by it. This simplifies the manufacturing process, improves the manufacturing accuracy, and improves the stability of the high-frequency field of the folded waveguide slow-wave structure. Attached Figure Description

[0016] Figure 1 A flowchart illustrating an integrated manufacturing method for a folded waveguide slow-wave assembly according to an embodiment of the present disclosure is shown schematically.

[0017] Figure 2 This schematic diagram illustrates a portion of a part after high-speed milling using a two-body independent structure, according to an embodiment of this disclosure.

[0018] Figure 3 This schematic diagram illustrates an electron beam channel fabricated using a two-body independent structure according to an embodiment of the present disclosure.

[0019] Figure 4 The diagram schematically illustrates the distribution of the electric field amplitude along the diameter direction of the electron beam channel after fabrication using a two-body independent structure according to an embodiment of the present disclosure.

[0020] Figure 5 A schematic diagram of one of the folded waveguide blank groove structures according to an embodiment of the present disclosure is shown.

[0021] Figure 6 A schematic diagram of the structure of one of the folded waveguide blanks according to an embodiment of the present disclosure is shown.

[0022] Figure 7This schematically illustrates a diffusion welding process on an assembled folded waveguide blank according to an embodiment of the present disclosure.

[0023] Figure 8 A schematic left view of a folded waveguide blank according to an embodiment of the present disclosure is shown;

[0024] Figure 9 A schematic front view of a blank welding assembly according to an embodiment of the present disclosure is shown;

[0025] Figure 10 This schematically illustrates a diagram of physical measurement of a target signal transmission channel of a billet welding assembly according to an embodiment of the present disclosure;

[0026] Figure 11 This illustration schematically shows a measurement of a target electron beam channel in a billet welding assembly according to an embodiment of the present disclosure;

[0027] Figure 12 This illustration schematically shows a boundary measurement of a target signal transmission channel for a billet welding assembly according to an embodiment of the present disclosure;

[0028] Figure 13 The schematic diagram illustrates the structure of the blank welding assembly and the cover plate encapsulation welding according to an embodiment of the present disclosure. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0030] However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this disclosure. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of embodiments of this disclosure 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 technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this disclosure.

[0031] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. The terms "comprising," "including," etc., as used herein indicate the presence of the described features, steps, or operations, but do not exclude the presence or addition of one or more other features, steps, or operations.

[0032] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0033] Traveling wave tubes are indispensable in applications such as radar, satellite communication, and electronic warfare systems. With the rapid development of mobile communication, satellite communication, and spaceborne electronics technologies, wireless communication spectrum resources are becoming increasingly scarce, and data transmission rates are required to reach higher speeds. Modern communication systems are increasingly demanding the terahertz frequency band.

[0034] Compared to traveling wave tubes (TWTs) in other bands, terahertz TWTs offer advantages such as wide bandwidth, low noise, and high power. Among these advantages, the metallic folded waveguide structure has become the preferred slow-wave structure for terahertz TWTs. Compared to the traditional helical slow-wave line structure, the entire slow-wave line of the folded waveguide is metallic, resulting in a robust structure and superior heat dissipation. Furthermore, the folded waveguide exhibits significantly lower high-frequency losses than the helical waveguide. Finally, the folded waveguide slow-wave line possesses weaker dispersion characteristics, resulting in a flatter dispersion profile and a wider bandwidth. Therefore, the folded waveguide slow-wave structure, as a novel all-metal slow-wave structure, not only solves the problems of heat dissipation difficulties and low power capacity but also offers wider bandwidth and higher data transmission rates.

[0035] Currently, to achieve the manufacturing process of folded waveguide slow-wave components in terahertz traveling wave tubes, the main method adopted is two-body independent high-speed milling and pin-aligned laser welding. First, the folded waveguide is divided into two independent upper and lower bodies along the axial direction, and then each is machined separately using high-speed milling. Next, the milled upper and lower bodies are pre-assembled using pins for positioning, and finally, the assembled upper and lower bodies are laser welded. However, because the high-speed milling of the blank first divides the electron beam channel into two independent parts, and then the pin-aligned laser welding is performed, this method of machining first and then splicing is prone to problems such as low alignment accuracy (≥0.02mm) and incomplete closure of the electron beam channel. This results in non-uniform disturbances in the high-frequency interaction field at the electron beam channel, affecting the continuity of the electric field distribution.

[0036] In order to at least partially solve the technical problems existing in the related art, this disclosure provides an integrated manufacturing method for folded waveguide slow wave components and a folded waveguide slow wave component.

[0037] Figure 1 A flowchart illustrating an integrated manufacturing method for a folded waveguide slow wave assembly according to an embodiment of the present disclosure is shown.

[0038] like Figure 1 As shown, the integrated manufacturing method for folded waveguide slow-wave components may include the following steps:

[0039] In operation S110, a groove structure is formed by cutting along the centerline on the surface of the folded waveguide blank.

[0040] According to an embodiment of this disclosure, before cutting a groove structure along the centerline on the surface of the folded waveguide blank, a folded waveguide blank needs to be prepared. Oxygen-free copper (TU1) can be selected as the main material of the folded waveguide blank during the preparation of the folded waveguide.

[0041] According to embodiments of this disclosure, a grinding machine can be used to cut and grind the folded waveguide blank to form two folded waveguide blanks with the same length, width, and shape.

[0042] According to embodiments of this disclosure, grinding is a process in which a grinding wheel or other abrasive tool rotates at high speed to cut away excess material from the surface of a workpiece.

[0043] According to embodiments of this disclosure, the surfaces of two folded waveguide blanks are ground so that the surface roughness of both blanks can be configured between Ra0.2 and Ra0.4 μm, and both meet a processing threshold. The processing threshold may include the flatness and parallelism of the folded waveguide blank surfaces. For example, the flatness of the contact surface of the two folded waveguide blanks can be configured to 0.01 mm, and the parallelism of the two folded waveguide blank surfaces can be configured to 0.02 mm.

[0044] According to an embodiment of this disclosure, after grinding is completed, a slow wire EDM process is used to cut groove structures along the center line on the surface of the two folded waveguide blanks respectively. The slow wire EDM process uses a continuously moving fine metal wire as an electrode to perform pulse spark discharge on the workpiece, generating a high temperature of over 6000°C to erode the metal or cut the workpiece.

[0045] According to embodiments of this disclosure, the cross-section of the groove structure is semi-circular, and the radius of the semi-circular cross-section can satisfy a radius threshold. For example, the radius threshold can be set to [0.04, 0.06] mm.

[0046] In operation S120, pin positioning holes are formed on both sides of the groove structure of the folded waveguide blank.

[0047] According to the embodiments of this disclosure, the positioning points of the pin positioning holes on the surfaces of the two folded waveguide blanks need to be determined first. The positioning points can be selected according to the design requirements and assembly requirements. For example, the positioning points can be set on both sides of the groove structure along the surfaces of the two folded waveguide blanks, or on both sides of the two ends of the groove structure.

[0048] According to embodiments of this disclosure, pin positioning holes matching the pins are machined on the surfaces of the two folded waveguide blanks to be positioned, according to the location of the positioning points.

[0049] According to embodiments of this disclosure, the number of pin positioning holes can be set according to the shape and surface area of ​​the folded waveguide blank, and the diameter and depth of the pin positioning holes can be set according to the size of the pin, so that the diameter and depth of the pin positioning holes need to match the size of the pin to ensure the accuracy and stability of positioning. For example, in an embodiment of this disclosure, eight pin positioning holes are provided symmetrically on both sides of the groove structure at both ends of the two folded waveguide blanks.

[0050] According to embodiments of this disclosure, after the positioning holes are machined on the surfaces of the two folded waveguide blanks, the surfaces of the folded waveguide blanks can be degreased and pickled to remove oxides or excess impurities from the surfaces of the folded waveguide blanks and the inner walls of the pin positioning holes.

[0051] According to embodiments of this disclosure, after cleaning, the dimensions of the processed folded waveguide blank, the position of the pin positioning hole, and the inner diameter of the pin positioning hole can be measured to ensure that the dimensions, inner diameter of the pin positioning hole, and position of the pin positioning hole of the two processed folded waveguide blanks are consistent, thereby facilitating the alignment of the pin positioning holes of the two folded waveguide blanks using pins.

[0052] In operation S130, two folded waveguide blanks are assembled so that the two folded waveguide blanks are aligned with the pin positioning holes, and the groove structures of the two folded waveguide blanks are aligned to form wire-threading holes, thus obtaining the assembled folded waveguide blanks.

[0053] According to an embodiment of this disclosure, after determining a plurality of pin positioning holes, one end of a pin is inserted into one of the pin positioning holes on the surface of the folded waveguide blank. The pin can be directly inserted into the pin positioning hole, or a tool can be used to gently tap the pin to ensure that it is fully inserted into the pin positioning hole.

[0054] According to embodiments of this disclosure, where the pin can be directly inserted into the pin positioning hole on one of the folded waveguide surfaces, screws or other fixing devices can also be used to fix the folded waveguide blank to the pin.

[0055] According to embodiments of this disclosure, when a pin is inserted into a pin positioning hole, it provides an accurate positioning point for another folded waveguide blank, allowing the other folded waveguide blank to be aligned and inserted with the pin positioning hole on the surface of the folded waveguide blank. The two folded waveguide blanks can also be fixed together with the pin using screws or other fixing devices to form an assembled folded waveguide blank, thereby ensuring the stability of the positioning of the two folded waveguide blanks and the accuracy of the assembly.

[0056] According to an embodiment of this disclosure, after two folded waveguide blanks are aligned and fixed, the groove structures of the two folded waveguide blanks are spliced ​​together to form a circular wire-threading hole, which facilitates the processing of the target electron beam channel.

[0057] In operation S140, diffusion welding is performed on the assembled folded waveguide blank to obtain the blank welding assembly.

[0058] According to embodiments of this disclosure, vacuum diffusion welding is suitable for welding folded waveguide blanks because it has the characteristics of small deformation, low residual stress, and high welding strength.

[0059] According to an embodiment of this disclosure, the assembled folded waveguide blank is placed in a diffusion welding equipment. In a cold state, the assembled folded waveguide blank is reinforced using a fixture and then heated. In this embodiment, the diffusion welding equipment can be a vacuum diffusion welding furnace. The heating method can be selected according to the material of the folded waveguide blank. For example, for folded waveguide blanks made of oxygen-free copper, flame heating or resistance heating can be selected. The diffusion welding temperature can be set to [940, 960]℃.

[0060] The upper pressure head of the diffusion welding equipment applies pressure to the blank. Under pressure, micro-plastic deformation occurs at the unevenness of the contact surface, ensuring that the upper and lower welding surfaces of the assembled folded waveguide blank fit tightly together. The diffusion welding pressure can be set to [0.2, 0.3] MPa.

[0061] According to embodiments of this disclosure, when the assembled folded waveguide blank is pressurized and fixed, the diffusion welding temperature must be maintained at a high temperature for a specified time threshold to achieve atomic diffusion exchange on the contact surface of the assembled folded waveguide blank. The holding time threshold can be set to [110, 130] minutes.

[0062] According to embodiments of this disclosure, after diffusion exchange is completed, a blank welding assembly is obtained. The temperature of the blank welding assembly is gradually reduced to room temperature, and the weld joint is cooled to improve the welding strength and prevent cracking, deformation, and other phenomena.

[0063] According to embodiments of this disclosure, during the diffusion welding process, the displacement accuracy error of diffusion welding must also be satisfied, wherein the displacement accuracy error range of diffusion welding can be set to [0.01, 0.03] mm.

[0064] According to embodiments of this disclosure, before performing diffusion welding on the assembled folded waveguide blank, a layer of liquid metal can be applied to the contact surface of the assembled folded waveguide blank to increase the diffusion effect.

[0065] According to the embodiments of this disclosure, in order to prevent voids in the weld joint and ensure the quality of diffusion welding of the folded waveguide blank, the welding surface of the folded waveguide blank needs to be kept smooth, that is, the roughness of the welding surface needs to meet Ra0.2~Ra0.4μm. Therefore, before diffusion welding of the assembled folded waveguide blank, the folded waveguide blank can be cleaned with alcohol and dried with a hair dryer to ensure that the surface is clean.

[0066] In operation S150, the inner wall of the wire-threading hole on the blank welding assembly is enlarged to form the target electron injection channel.

[0067] According to embodiments of this disclosure, a slow wire EDM method is used to enlarge the inner wall of the wire-piercing hole in the blank welding assembly, so that the machining accuracy of the wire-piercing hole meets the wire-piercing hole accuracy threshold, and the surface roughness of the inner wall of the wire-piercing hole meets the wire-piercing hole roughness threshold, thereby completing the machining of the target electron beam channel. For example, in embodiments of this disclosure, the wire-piercing hole accuracy threshold error can be set to [-2.5, +2.5] μm, and the wire-piercing hole roughness threshold can be set to Ra0.4 μm.

[0068] According to embodiments of this disclosure, the inner diameter of the wire-threading hole varies depending on the terahertz band and the waveguide power. For example, in embodiments of this disclosure, the wire-threading hole can be enlarged from a diameter of 0.1 mm to a diameter of 0.4 mm.

[0069] In operation S160, the outer surface of the blank welding assembly corresponding to the target electron injection channel is cut through the blank welding assembly to form the target signal transmission channel.

[0070] According to an embodiment of this disclosure, a slow wire EDM method is used to cut the outer surface of the blank welding assembly corresponding to the target electron beam channel, so as to cut out a target signal transmission channel that penetrates the outer surface of the blank welding assembly corresponding to the target electron beam channel, so that the machining accuracy of the target signal transmission channel meets the machining accuracy threshold and the surface roughness meets the roughness threshold, thereby completing the machining of the target signal transmission channel.

[0071] For example, in embodiments of this disclosure, the processing accuracy threshold of the target signal transmission channel can be set to [-2.5, +2.5] μm, and the surface roughness threshold of the target signal transmission channel can be set to Ra0.4 μm.

[0072] According to embodiments of this disclosure, the target signal transmission channel may be a serpentine channel comprising at least one set of waveguides that are bent in parallel.

[0073] For example, by performing slow wire EDM on the assembled folded waveguide blank, the assembled folded waveguide blank can be cut into a structure with a vertical cross section of convex shape, and a serpentine channel that runs through the top of the convex shape can be cut on both sides of the top of the convex shape using a slow wire EDM.

[0074] According to embodiments of this disclosure, since the wavelength of terahertz waves is reduced to sub-millimeter (0.03mm to 3mm), the size of the folded waveguide is small, thus requiring high processing accuracy and surface roughness. To achieve the above processing accuracy and surface roughness thresholds, slow wire EDM employs a multi-cut processing method, typically using a cut-and-repair approach. As the number of cuts increases, the cutting allowance decreases, the pulse intensity decreases, and the surface quality improves.

[0075] For example, embodiments of this disclosure may employ a five-step processing method to ensure that the processing accuracy of both the target electron beam channel and the target signal transmission channel, i.e., the serpentine channel, reaches ±2.5μm, and the surface roughness reaches Ra0.4μm, thereby meeting the processing accuracy and roughness requirements of the folded waveguide slow wave structure.

[0076] According to embodiments of this disclosure, after the processing of the target signal transmission channel is completed, the target signal transmission channel can also be degreased and cleaned to remove excess oxides on the surface, and the cleaned target signal transmission channel can be dried with cold air and placed in a dust-free box.

[0077] According to embodiments of this disclosure, after processing the target signal transmission channel and the target electron beam channel, dimensional inspection can also be performed on the target signal transmission channel and the target electron beam channel.

[0078] According to embodiments of this disclosure, the inspection tool can be a non-contact high-precision image measuring instrument, and the inspection method can include top-light inspection and bottom-light inspection. Top-light inspection projects light from above the object, making the object's surface bright and generating more reflections, thus providing better results for highly reflective surfaces, such as metals. Bottom-light inspection projects light from the bottom of the object, revealing important features such as defects, edges, and contours, and is suitable for objects that are not easily reflective, such as porcelain and plastics.

[0079] For example, in the embodiments of this disclosure, a non-contact high-precision image measuring instrument can be used for bottom light detection to detect the target signal transmission channel and the target electron beam channel. First, light is shone into the target electron beam channel. Since the target signal transmission channel penetrates the outer wall of the target electron beam channel during cutting, that is, the target signal transmission channel is transparent, bottom light detection makes it easier to capture the boundary of the target signal transmission channel, thereby more accurately measuring the boundary size of the target signal transmission channel.

[0080] In operation S170, the blank welding assembly with the target electron injection channel and the target signal transmission channel is welded to the cover plate to form a folded waveguide slow wave assembly.

[0081] According to an embodiment of this disclosure, two cover plates are used to cover the target signal transmission channel on both sides, and the seam between the cover plates and the target signal transmission channel can be fixed by laser welding, thereby forming a folded waveguide slow wave assembly.

[0082] The embodiments of this disclosure propose an integrated manufacturing method for folded slow-wave components. Two folded waveguide blanks are first aligned and diffused welded according to the pin positioning holes and wire threading holes. Then, the target signal transmission channel and target electron beam channel of the blank welding assembly are integratedly processed. This avoids the channel misalignment problem that occurs when the two blanks are aligned with pins after the channels are processed, as well as the disturbance problem of non-uniform high-frequency field of interaction caused by it. This simplifies the manufacturing process, improves the manufacturing accuracy, and improves the stability of the high-frequency field of the folded waveguide slow-wave structure.

[0083] In one embodiment, a process combining high-speed milling of the upper and lower bodies with pin-positioning laser welding is used to manufacture the folded waveguide slow wave assembly.

[0084] The following is for reference. Figures 2-4 The present disclosure further describes the process of manufacturing a folded waveguide slow wave component using a combination of high-speed milling of upper and lower bodies and pin positioning laser welding in one embodiment.

[0085] Figure 2 The illustration shows a partial part after high-speed milling using a two-body independent structure according to an embodiment of the present disclosure.

[0086] Figure 3 The diagram illustrates an embodiment of the present disclosure of an electron injection channel fabricated using a two-body independent structure.

[0087] Figure 4 The diagram illustrates the distribution of the electric field amplitude along the diameter direction of the electron beam channel after processing using a two-body independent structure according to an embodiment of the present disclosure.

[0088] Specifically, the upper and lower blanks are first subjected to high-speed milling (accuracy ±0.005mm) to mill out the electronic injection channel and serpentine lines, such as... Figure 2The part shown is a high-speed milled part from a single blank. After milling, the upper and lower bodies are cleaned and degreased to remove excess material and oxides from the milled surfaces. Next, the serpentine dimensions of the upper and lower bodies are measured using a high-precision optical image measuring instrument. Then, the upper and lower bodies of the folded waveguide are visually aligned with the serpentine lines and electron beam channels, pre-assembled using pins for positioning, and finally fixed with laser welding to complete the manufacturing of the folded waveguide slow-wave structure.

[0089] However, in the actual development process, due to the pin positioning accuracy >0.02mm, when assembling the upper and lower parts of the folded waveguide, the upper and lower parts inevitably experience front-to-back and left-to-right misalignment, which leads to misalignment of the electron injection channel edge.

[0090] like Figure 3 and Figure 4 As shown, the misalignment at the edge of the electron beam channel causes fluctuations and discontinuities in the electric field amplitude along the diameter of the electron beam channel. Furthermore, the lack of transparency between the upper and lower bodies results in unclear boundaries for the serpentine line, increasing the difficulty for the image measuring instrument to capture these boundaries and affecting the measurement accuracy of the folded waveguide serpentine line. Both of these factors impact the high-frequency performance of the terahertz traveling wave tube. Simultaneously, due to the extremely small size and high surface roughness requirements of the folded waveguide serpentine line and the electron beam channel, conventional high-speed milling processes place high demands on equipment, machining processes, and cutting tools, resulting in high costs, long development cycles, and low yields.

[0091] In another embodiment, the electron beam channel is drilled using electrical discharge machining (EDM), and the serpentine line of the electromagnetic wave transmission channel is machined using micro-milling or EDM. However, in actual research and production, since the radius of the electron beam channel is about 0.2 mm, the depth of EDM drilling can only reach about 20 mm. When the electron beam channel depth exceeds 20 mm, with the consumption of slender electrodes, the electron beam channel drilled by EDM is prone to problems such as tapering and dimensional deviations. On the other hand, in the design of terahertz traveling wave tubes, in order to achieve the power and gain of the terahertz traveling wave tube, the length of the output folded waveguide must be ≥50 mm. This brings great difficulties to EDM drilling of the electron beam channel and also increases the difficulty of realizing the folded waveguide slow wave structure process.

[0092] The following is for reference. Figures 5-13 The integrated manufacturing method of the folded waveguide slow wave component according to the embodiments of this disclosure will be further described.

[0093] First, a folded waveguide blank needs to be prepared. The folded waveguide blank is then ground using a grinding machine to cut and grind it into two folded waveguide blanks with the same length, width, and shape.

[0094] The surfaces of the two folded waveguide blanks are ground so that the surface roughness of both blanks can be set between Ra0.2 and Ra0.4μm, and both blanks meet the flatness and parallelism of the contact surfaces. The flatness can be configured to 0.01mm and the parallelism can be configured to 0.02mm.

[0095] Preferably, the surface roughness of both folded waveguide blanks can be set to values ​​such as Ra0.2μm, Ra0.3μm, and Ra0.4μm.

[0096] After grinding, a slow wire EDM process is used to cut groove structures along the center line on the surface of the two folded waveguide blanks.

[0097] Figure 5 The schematic diagram illustrates a structural schematic of one of the folded waveguide blank groove structures according to an embodiment of the present disclosure.

[0098] like Figure 5 As shown, one of the folded waveguide blanks 1 includes a groove structure 11, the cross-section of which is semi-circular, and the radius of the semi-circular cross-section can meet a radius threshold. For example, the radius threshold can be set to [0.04, 0.06] mm.

[0099] Preferably, the radius threshold can be set to 0.04mm, 0.05mm, 0.055mm, etc.

[0100] Pin positioning holes can be machined on the surface of the folded waveguide blank using a slow wire EDM process. Specifically, the positioning points of the pin positioning holes on the surfaces of the two folded waveguide blanks are determined, and pin positioning holes matching the pins are machined on the surfaces of the two folded waveguide blanks that need to be positioned, according to the positions of the positioning points.

[0101] Figure 6 The schematic diagram illustrates the structure of one of the folded waveguide blanks according to an embodiment of the present disclosure.

[0102] like Figure 6 As shown, one of the folded waveguide blanks 1 includes a groove structure 11 and pin positioning holes 12. Eight pin positioning holes 12 of the same size and shape are provided symmetrically on both sides of the groove structure 11 at both ends of the folded waveguide blank 1. The other folded waveguide blank has the same configuration as the first folded waveguide blank 1.

[0103] After the pin positioning holes are machined on the surfaces of the two folded waveguide blanks, the surfaces of the folded waveguide blanks need to be degreased and pickled to remove oxides or excess impurities from the surfaces of the folded waveguide blanks and the inner walls of the pin positioning holes.

[0104] After cleaning, the dimensions of the processed folded waveguide blanks, the position of the pin positioning holes, and the inner diameter of the pin positioning holes can be measured to ensure that the dimensions, inner diameter of the pin positioning holes, and position of the pin positioning holes of the two processed folded waveguide blanks are consistent, thus facilitating the alignment of the pin positioning holes of the two folded waveguide blanks using pins.

[0105] After determining multiple pin positioning holes, insert one end of the pin into one of the pin positioning holes on the surface of the folded waveguide blank, and use screws or other fastening devices to fix the folded waveguide blank to the pin.

[0106] When the pin is inserted into the pin positioning hole, it provides an accurate positioning point for another folded waveguide blank, so that the other folded waveguide blank can be aligned and inserted with the pin positioning hole on the surface of the first folded waveguide blank. The two folded waveguide blanks can also be fixed together with the pin using screws or other fixing devices to form the assembled folded waveguide blank.

[0107] After aligning and fixing the two folded waveguide blanks after they are aligned and plugged together, the groove structures of the two folded waveguide blanks are spliced ​​together to form a circular wire-passing hole. The contact surfaces of the assembled folded waveguide blanks are then diffused and welded to obtain the blank welding assembly.

[0108] Figure 7 The schematic diagram illustrates the diffusion welding of the assembled folded waveguide blank according to an embodiment of the present disclosure.

[0109] like Figure 7 As shown, one folded waveguide blank 1 and another folded waveguide blank 2 are aligned and spliced ​​to form an assembled folded waveguide blank, and the groove structure 11 of one folded waveguide blank 1 and the groove structure 21 of the other folded waveguide blank 2 are spliced ​​to form a circular wire-threading hole with a radius of 0.05±0.01mm.

[0110] The assembled folded waveguide blank is placed in a vacuum diffusion welding furnace. The assembled folded waveguide blank is reinforced in a cold state and then heated. The diffusion welding temperature can be set to [940, 960]℃. Preferably, the diffusion welding temperature can be set to 945℃, 950℃, 955℃, etc.

[0111] The upper pressure head of the diffusion welding equipment applies pressure to the billet, such as Figure 7 As shown, Figure 7The arrows indicate the direction in which the upper pressure head applies pressure to the assembled folded waveguide blank. Under pressure, micro-plastic deformation occurs at the unevenness of the contact surface, ensuring a tight fit between the upper and lower welding surfaces of the assembled folded waveguide blank. The diffusion welding pressure can be set to [0.2, 0.3] MPa, preferably 0.22 MPa, 0.25 MPa, 0.28 MPa, etc.

[0112] When the assembled folded waveguide blank is pressurized and fixed, the diffusion welding temperature must be maintained at a high temperature for a specified holding time threshold to achieve atomic diffusion exchange on the contact surface of the assembled folded waveguide blank. The holding time threshold can be set to [110, 130] minutes. Preferably, the holding time threshold can be set to 112 minutes, 115 minutes, 120 minutes, 125 minutes, etc.

[0113] After diffusion exchange is completed, a blank welding assembly is obtained. The temperature of the blank welding assembly is gradually reduced to room temperature, and the weld joint is cooled to improve the welding strength. During diffusion welding, the displacement accuracy error must also be met. The displacement accuracy error range can be set to [0.01, 0.03] mm. Preferably, the displacement accuracy error can be set to 0.015 mm, 0.02 mm, etc.

[0114] To prevent voids in the weld joints and ensure the quality of diffusion welding of the folded waveguide blank, the welding surface of the folded waveguide blank needs to be kept smooth, that is, the surface roughness of the welding surface needs to meet Ra0.2~Ra0.4μm. Therefore, before diffusion welding the assembled folded waveguide blank, the folded waveguide blank can be cleaned with alcohol and dried with a hair dryer to ensure that the surface is clean.

[0115] The inner wall of the wire-threading hole of the blank welding assembly is enlarged using a slow wire EDM method.

[0116] Figure 8 A schematic left view of a folded waveguide blank according to an embodiment of the present disclosure is shown.

[0117] like Figure 8 As shown, slow wire cutting can be used to cut the assembled folded waveguide blank into a convex structure 3. On the convex structure 3, the groove structure 11 of one folded waveguide blank 1 and the groove structure 21 of another folded waveguide blank 2 are aligned and spliced ​​to form a wire-passing hole with a diameter of 0.1 mm to a diameter of 0.4 mm. The wire-passing hole after expansion forms the target electronic main channel 31.

[0118] Furthermore, the machining accuracy of the target electron main channel 31 is made to meet the wire-threading hole accuracy threshold. The accuracy threshold error of the target electron main channel 31 can be set to [-2.5, +2.5] μm, preferably -2 μm, +1.5 μm, etc. The surface roughness of the inner wall of the target electron main channel 31 meets the target electron main channel roughness threshold, which can be set to Ra0.4 μm. This completes the machining of the target electron injection channel 31.

[0119] Figure 9 A schematic front view of a blank welding assembly according to an embodiment of the present disclosure is shown.

[0120] like Figure 9 As shown, a slow wire EDM method is used to cut the outer surface of the convex structure 3 of the blank welding assembly corresponding to the target electron beam channel 31, so as to cut out a serpentine target signal transmission channel 32 that penetrates the outer surface of the blank welding assembly and the target electron beam channel 31. The machining accuracy threshold error of the target signal transmission channel 31 can be set to [-2.5, +2.5] μm, preferably -2 μm, +1.5 μm, etc. The surface roughness threshold of the target signal transmission channel 31 can be set to Ra 0.4 μm.

[0121] After the processing of the target signal transmission channel is completed, the target signal transmission channel can be degreased and cleaned to remove excess oxides on the surface. The cleaned target signal transmission channel is then dried with cold air and placed in a dust-free box.

[0122] After the processing of the target signal transmission channel and the target electron beam channel is completed, the dimensions of the target signal transmission channel and the target electron beam channel can also be inspected.

[0123] Figure 10 This illustration schematically shows a physical measurement of the target signal transmission channel of a billet welding assembly according to an embodiment of the present disclosure.

[0124] like Figure 10 As shown, the length of the target signal transmission channel was roughly measured using a steel ruler, and the length of the target signal transmission channel was found to be 6.55 cm.

[0125] Figure 11 The illustration shows a schematic diagram of measuring a target electron injection channel of a billet welding assembly according to an embodiment of the present disclosure.

[0126] Figure 12 This illustration schematically shows a boundary measurement of a target signal transmission channel for a billet welding assembly according to an embodiment of the present disclosure.

[0127] After the rough measurement, a non-contact, high-precision image measuring instrument can be used for bottom-light detection to inspect the target signal transmission channel and the target electron beam channel. First, light is shone into the target electron beam channel, such as... Figure 11 It can be seen that there is no misalignment problem at the joint of the target electron injection channel.

[0128] like Figure 12 As shown, since the target signal transmission channel penetrates the outer wall of the target electron beam channel during cutting, meaning the target signal transmission channel is transparent, bottom light detection makes it easier to capture the boundary of the target signal transmission channel, thus allowing for more accurate measurement of the boundary dimensions of the target signal transmission channel.

[0129] Figure 13 The schematic diagram illustrates the structure of the blank welding assembly and the cover plate encapsulation welding according to an embodiment of the present disclosure.

[0130] like Figure 13 As shown, two cover plates 4 can be used on both sides of the target signal transmission channel 32 to cover and seal the target signal transmission channel 32 on the convex structure 3, and the joint between the cover plate 3 and the convex structure 3 can be fixed by laser welding, thereby forming a folded waveguide slow wave component.

[0131] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or combinations fall within the scope of this disclosure.

[0132] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An integrated manufacturing method for a folded waveguide slow-wave assembly, comprising: A groove structure is formed by cutting along the centerline on the surface of the folded waveguide blank; Pin positioning holes are formed on both sides of the groove structure of the folded waveguide blank; Assemble two folded waveguide blanks such that the two folded waveguide blanks are aligned according to the pin positioning holes, and the groove structures of the two folded waveguide blanks are aligned to form wire-threading holes, thereby obtaining the assembled folded waveguide blanks. The assembled folded waveguide blank is subjected to diffusion welding to obtain a blank welding assembly; The inner wall of the wire-threading hole on the blank welding assembly is enlarged to form a target electron injection channel; The outer surface of the blank welding assembly corresponding to the target electron injection channel is cut to penetrate the blank welding assembly and form a target signal transmission channel; The blank welding assembly having the target electron injection channel and the target signal transmission channel is welded to the cover plate to form a folded waveguide slow wave assembly.

2. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, The cross-section of the groove structure is semi-circular; The pin positioning holes are formed on both sides of the groove structure of the folded waveguide blank, including: Positioning points that need to be positioned are determined on the surfaces of the two folded waveguide blanks, wherein the positioning points are located on both sides of the two ends of the groove structure. According to the location of the positioning point, the pin positioning hole is machined to match the pin size.

3. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, The assembly of two folded waveguide blanks, such that the two folded waveguide blanks are aligned according to the pin positioning holes, and the groove structures of the two folded waveguide blanks are spliced ​​together to form wire-passing holes, yields an assembled folded waveguide blank comprising: Insert one end of the pin into the pin positioning hole of one of the folded waveguide blanks; Align and insert the pin positioning hole of the other folded waveguide blank with the other end of the pin and fix it, so that the groove structure of each of the two folded waveguide blanks is spliced ​​together to form a wire threading hole, thus forming the assembled folded waveguide blank.

4. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, The diffusion welding of the contact surfaces of the assembled folded waveguide blank to obtain the blank welding assembly includes: The assembled folded waveguide blank is placed in a diffusion welding device, and the assembled folded waveguide blank is reinforced with a fixture in a cold state. The assembled folded waveguide blank, which has been fixed, is then heated. The upper pressure head of the diffusion welding equipment performs pressure diffusion welding on the heated folded waveguide blank to obtain the blank welding assembly.

5. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 4, wherein, The welding conditions for diffusion welding include: diffusion welding temperature, holding time, diffusion welding pressure, and diffusion welding displacement; The diffusion welding temperature includes [940, 960] °C; The heat preservation time includes [110, 130] minutes; The diffusion welding pressure includes [0.2, 0.3] MPa; The diffusion welding displacement includes [0.01, 0.03] mm.

6. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, Before the groove structure is formed by cutting along the centerline on the surface of the folded waveguide blank, the method further includes: The surface of the folded waveguide blank is ground using a grinding machine to obtain two folded waveguide blanks with identical shape and size.

7. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, The signal transmission channel includes a serpentine channel.

8. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 1, wherein, The step of welding the blank welding assembly having the target electron injection channel and the target signal transmission channel to the cover plate to obtain the folded waveguide slow wave structure includes: Cover the outer surface of the target signal transmission channel with the cover plate; The contact surface between the cover plate and the outer surface of the target signal transmission channel is welded to obtain a folded waveguide slow wave structure.

9. The integrated manufacturing method of the folded waveguide slow wave assembly according to claim 8, wherein, Laser welding was used for the welding.

10. A folded waveguide slow-wave assembly, wherein, The folded waveguide slow wave assembly is obtained by an integrated manufacturing method according to any one of claims 1-9.

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