High-power microwave generator and method convenient for in-situ characterization of breakdown damage trace

Abstract

The invention discloses a high-power microwave generator and method convenient for in-situ characterization of breakdown damage traces, and belongs to the technical field of high-power microwaves. A split type slow wave structure is arranged in the sleeve, and an outer cylinder is arranged outside the sleeve; a sealing ring is fixedly connected to the inner wall of the outer cylinder, and a limiting ring is fixedly connected to one side of the outer cylinder; the inner wall of the limiting ring is connected with the hollow circular waveguide through threads. A vertical groove parallel to the center axis of the outer cylinder and an annular groove communicated with the vertical groove are formed in the inner wall of the other side of the outer cylinder. According to the invention, the split slow-wave structure is formed by a plurality of slow-wave structure rings, so that observation and detection of the microtopography and elemental components of the breakdown damage trace on the working surface of the Cherenkov type device can be realized on the premise of not damaging the metal structure, and the method has the outstanding advantages of low cost, simple operation and the like; and in the installation process, the situation that the slow wave structure between the hollow circular waveguide and the limiting ring is annularly changed due to overlarge pressure between the hollow circular waveguide and the limiting ring, and then the experiment result is influenced can be effectively avoided.

Description

Technical Field

[0001] The invention relates to a high-power microwave generator and a method for facilitating in-situ characterization of breakdown damage traces, and belongs to the technical field of high-power microwaves. Background Art

[0002] High-power microwave generators are the core components of high-power microwave weapon systems. Currently, the most widely used high-power microwave generators include Cherenkov devices, transit time oscillators, virtual cathode oscillators, etc. Among them, the Cherenkov high-power microwave generator has the advantages of compact structure, large power capacity, and high conversion efficiency. It is one of the high-power microwave generators with the most application potential. The Cherenkov device uses the high-voltage pulse generated by the pulse power source to drive the annular explosive emission cathode of the vacuum diode to produce a strong relativistic electron beam. The relativistic electron beam passes through the high-frequency structure under the guidance of the axial external magnetic field, and interacts with the electromagnetic waves therein to produce high-power microwaves; the energy of the electron beam after the interaction is deposited on the collector, and the generated high-power microwaves are radiated to the atmosphere through transmission and radiation components such as mode converters, feed horns, and dielectric windows.

[0003] In order to meet the demand for stronger destructive capability of high-power microwave weapons, the microwave output power, conversion efficiency, microwave frequency and pulse energy of Cherenkov high-power microwave generators need to be further expanded. As Cherenkov devices develop towards higher power, efficiency and microwave frequency, the electromagnetic field inside the high-frequency structure of the device will be further enhanced; and as Cherenkov devices develop towards longer pulse widths and larger pulse energies, the strong electromagnetic field will exist for a longer time. At this time, the risk of strong electromagnetic field vacuum breakdown inside the high-frequency structure of the device will increase significantly. Strong electromagnetic field vacuum breakdown refers to a plasma breakdown phenomenon developed inside the high-frequency structure of the Cherenkov high-power microwave generator under the action of a strong microwave field. Strong electromagnetic field vacuum breakdown will not only have a direct impact on the microwave generation of the Cherenkov device, resulting in pulse shortening and frequency drift of high-power microwaves, but also cause damage to the metal inner wall structure, seriously restricting the working performance and service life of the device. When the output power of the Cherenkov high-power microwave generator is low or the number of operating pulses is small, the breakdown damage on the surface of the structure is relatively mild, usually manifested as discretely distributed spot-like breakdown marks near the small radius position. As the output power of the device increases or the number of operating pulses increases, the spot-like breakdown marks will gradually increase and connect into pieces, eventually forming serious breakdown damage. Based on this, strong electromagnetic field vacuum breakdown is the key technical bottleneck and urgent technical problem that currently restricts the physical performance of Cherenkov type high-power microwave generators.

[0004] In order to study the physical mechanism of the formation of breakdown damage, the researchers proposed to place the breakdown damage traces of the Cherenkov high-power microwave generator under a scanning electron microscope to observe the microscopic morphology of the breakdown damage traces, and then analyze and study the generation mechanism of the breakdown damage traces and the formation process of strong electromagnetic field vacuum breakdown. However, the radius and length of the tube body of the Cherenkov high-power microwave generator are generally much larger than the size of the scanning electron microscope stage. Therefore, it is necessary to wire-cut the tube body of the Cherenkov device multiple times to obtain a sample that can be placed on the scanning electron microscope stage, so as to observe the microscopic morphology of the breakdown damage traces on the working surface of the Cherenkov high-power microwave generator. However, during the wire cutting process, when the cut material reaches its own melting point locally, a large number of droplets will be sputtered and fall to the nearby working surface. After the droplets cool, they will form a stable bond with the working surface. Therefore, the working surface of the Cherenkov device after wire cutting will become rough and feel like sandpaper. At this time, a large number of spherical or disc-shaped particles with sizes ranging from μm to hundreds of μm adhere to the surface of the metal material; and the adhered particles form a stable bond with the working surface, which is difficult to remove by ultrasonic cleaning and other means. The presence of a large number of adhered particles seriously interferes with the observation of the original morphology of the breakdown damage traces of the Cherenkov type high-power microwave generator after the high-power microwave experiment. Therefore, improvements are proposed. Summary of the invention

[0005] The purpose of the present invention is to solve the above-mentioned problems existing in the background technology and to provide a high-power microwave generator and method for facilitating in-situ characterization of breakdown damage traces.

[0006] The present invention achieves the above-mentioned purpose by adopting the following technical solutions:

[0007] A high-power microwave generator for facilitating in-situ characterization of breakdown damage marks comprises a high-frequency structure; the high-frequency structure comprises a sleeve; a split slow-wave structure is arranged in the sleeve, and an outer sleeve is arranged outside the sleeve; a sealing ring is fixedly connected to the inner wall of the outer sleeve, and a limiting ring is fixedly connected to one side of the outer sleeve; the inner wall of the limiting ring is connected to a hollow circular waveguide via a thread; a vertical groove parallel to the central axis and an annular groove connected to the vertical groove are arranged on the inner wall of the other side of the outer sleeve; a sliding block slidably matched with the vertical groove and the annular groove is arranged in the vertical groove and the annular groove, and the sliding block is fixedly connected to the outer wall of the sliding cylinder; the sliding cylinder is slidably matched with the gap between the sleeve and the outer cylinder, and the limiting ring is connected to the inner wall of the sliding cylinder via a bearing.

[0008] A method for using a high-power microwave generator that facilitates in-situ characterization of breakdown damage traces, the method comprising the following steps:

[0009] Step 1: Assemble multiple slow-wave structure rings to form a usable Cherenkov-type high-power microwave generator;

[0010] Step 2: Conduct high-power microwave experiments using the assembled Cherenkov-type high-power microwave generator;

[0011] Step 3: After the high-power microwave experiment, the split slow-wave structure is disassembled;

[0012] Step 4: Place the slow-wave structure ring on the sample stage of a scanning electron microscope and an energy spectrometer, and characterize the microscopic morphology based on the scanning electron microscope and the energy spectrometer.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention can observe and detect the microscopic morphology and elemental composition of the breakdown damage marks on the working surface of the Cherenkov-type device without destroying the metal structure by forming a split slow-wave structure through multiple slow-wave structure rings. It not only has the outstanding advantages of low cost and simple operation, but also can effectively avoid the situation in which excessive pressure between the hollow circular waveguide and the limit ring causes the slow-wave structure located between the two to deform in a ring shape, thereby affecting the experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the three-dimensional structure of the high-power microwave generator of the present invention which is convenient for in-situ characterization of breakdown damage traces;

[0015] Figure 2 It is a schematic structural diagram of an outer cylinder of a high-power microwave generator for facilitating in-situ characterization of breakdown damage traces of the present invention;

[0016] Figure 3 It is a schematic structural diagram of a hollow circular waveguide of a high-power microwave generator that is convenient for in-situ characterization of breakdown damage traces of the present invention;

[0017] Figure 4 It is a schematic structural diagram of a slide barrel of a high-power microwave generator for facilitating in-situ characterization of breakdown damage traces of the present invention;

[0018] Figure 5 It is a schematic structural diagram of a split slow-wave structure of a high-power microwave generator that facilitates in-situ characterization of breakdown damage traces of the present invention;

[0019] Figure 6 is a cross-sectional view of a high-power microwave generator for facilitating in-situ characterization of breakdown damage traces of the present invention;

[0020] Figure 7 This is a schematic diagram of the working principle of a Cherenkov device.

[0021] In the figure: 1. outer cylinder; 11. vertical groove; 12. annular groove; 13. sealing ring; 14. connecting ring; 2. hollow circular waveguide; 3. sliding cylinder; 31. limiting ring; 32. sliding block; 33. arc groove; 34. arc pull rod; 4. slow wave structure ring; 5. sleeve; 6. high frequency structure. DETAILED DESCRIPTION

[0022] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0023] Specific implementation method 1: Figure 1-7 As shown, this embodiment records a high-power microwave generator that is convenient for in-situ characterization of breakdown damage traces, including a high-frequency structure 6; the high-frequency structure 6 includes a sleeve 5; a split slow-wave structure is arranged in the sleeve 5, and an outer cylinder 1 is arranged outside the sleeve 5; a gap is left between the sleeve 5 and the outer cylinder 1, and a sealing ring 13 is fixedly connected to the inner wall of the outer cylinder 1. The sealing ring 13 between the outer cylinder 1 and the sleeve 5 can increase friction and prevent the two from sliding relative to each other; a connecting ring 14 is fixedly connected to one side of the outer cylinder 1; the inner wall of the connecting ring 14 is connected to the hollow circular waveguide 2 through a thread; a vertical groove 11 parallel to the central axis and an annular groove 12 connected to the vertical groove 11 are provided on the inner wall of the other side of the outer cylinder 1; a slider 32 that slides with them is provided in the vertical groove 11 and the annular groove 12; the slider 32 is fixedly connected to the outer wall of the slide cylinder 3; the slide cylinder 3 slides with the gap between the sleeve 5 and the outer cylinder 1, and a limit ring 31 is connected to the inner wall of the slide cylinder 3 through a bearing.

[0024] The split slow-wave structure is composed of a plurality of slow-wave structure rings 4, so that the slow-wave structure rings 4 can be observed without cutting.

[0025] The outer diameter of the slow-wave structure ring 4 is equal to the inner diameter of the sleeve 5 .

[0026] The hollow circular waveguide 2 is coaxial with the sleeve 5 .

[0027] The hollow circular waveguide 2 and the limiting ring 31 are respectively against two ends of the split slow-wave structure.

[0028] The outer side of the limiting ring 31 is provided with an arc groove 33, and a rotatable arc pull rod 34 is provided in the arc groove 33. By rotating the arc pull rod 34, the slide cylinder 3 can be pulled out and put in. When not in use, the arc pull rod 34 can be put into the arc groove 33. The arc pull rod 34 is hinged to the inner wall of the arc groove 33 through a rotating shaft, and the rotating shaft is fixed on the inner wall of the arc groove 33. The other end of the rotating shaft is interference fit with the arc pull rod 34, reducing the possibility of the arc pull rod 34 automatically coming out of the arc groove 33.

[0029] When the limit ring 31 contacts the split slow-wave structure, the slider 32 can slide into the annular groove 12. The annular groove 12 and the slider 32 are interference-fitted to prevent the slide cylinder 3 from sliding and changing position at will, causing the slow-wave structure ring 4 to loosen. An identification line is provided on the outer circumferential surface of the slide cylinder 3, and the identification line is flush with the end of the outer cylinder 1 at this time;

[0030] When the hollow circular waveguide 2 is screwed in, if the screw-in depth is too large, the hollow circular waveguide 2 will push the slow-wave structure ring 4 to move, thereby driving the limit ring 31 to move, so that the limit ring 31 drives the slide cylinder 3 and the slider 32 to move along the direction of the vertical groove 11, thereby causing the slider 32 to break away from the position of the annular groove 12. At this time, the marking line on the outside of the slide cylinder 3 is separated from the outer cylinder 1, and the operator can make timely adjustments to ensure safe installation. The design that the limit ring 31 can move relative to the sleeve 5 can effectively avoid operating errors by the staff when the hollow circular waveguide 2 is screwed in, resulting in excessive pressure between the limit ring 31 and the hollow circular waveguide 2, thereby causing the slow-wave structure ring 4 located between the two to deform, thereby affecting subsequent tests.

[0031] A method for using a high-power microwave generator that facilitates in-situ characterization of breakdown damage traces, the method comprising the following steps:

[0032] Step 1: Place multiple slow-wave structure rings 4 in the sleeve 5, and then screw into the hollow circular waveguide 2 through threads, so that the hollow circular waveguide 2 pushes the slow-wave structure ring 4 to move until the slow-wave structure ring 4 at the other end contacts the limit ring 31, and stop rotating the hollow circular waveguide 2. At this time, the slow-wave structure rings 4 contact each other, and then rotate the slide cylinder 3 to make the slider 32 slide into the annular groove 12 to prevent the slide cylinder 3 from detaching and causing the slow-wave structure ring 4 to loosen; so as to form a usable Cherenkov type high-power microwave generator;

[0033] Step 2: Conduct high-power microwave experiments using the assembled Cherenkov-type high-power microwave generator;

[0034] Step 3: After the high-power microwave experiment, the hollow circular waveguide 2 is rotated to separate it from the connecting ring 14, and then the slide cylinder 3 is rotated to make the slider 32 located in the vertical groove 11, and the slide cylinder 3 is pulled to separate it from the sleeve 5, and then the slow-wave structure ring 4 can be taken out from both sides to disassemble the split slow-wave structure;

[0035] Step 4: Place the slow-wave structure ring 4 on the sample stage of a scanning electron microscope and an energy spectrometer, and characterize the microscopic morphology based on the scanning electron microscope and the energy spectrometer.

[0036] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other forms of assembly without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0037] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A high-power microwave generator that facilitates in-situ characterization of breakdown damage traces, characterized by: The invention comprises a high-frequency structure (6); the high-frequency structure (6) comprises a sleeve (5); a split-type slow-wave structure is arranged in the sleeve (5), and an outer sleeve (1) is arranged outside the sleeve (5); a sealing ring (13) is fixedly connected to the inner wall of the outer sleeve (1), and a connecting ring (14) is fixedly connected to one side of the outer sleeve (1); the inner wall of the connecting ring (14) is connected to the hollow circular waveguide (2) through a thread; a vertical groove (11) parallel to the central axis and an annular groove (12) connected to the vertical groove (11) are arranged on the inner wall of the other side of the outer sleeve (1); a sliding block (32) slidably matched with the vertical groove (11) and the annular groove (12) are arranged in the vertical groove (11) and the annular groove (12), and the sliding block (32) is fixedly connected to the outer wall of the sliding cylinder (3); the gap between the sliding cylinder (3) and the sleeve (5) and the outer cylinder (1) is slidably matched, and a limiting ring (31) is connected to the inner wall of the sliding cylinder (3) through a bearing.

2. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claim 1, characterized in that: The split-type slow-wave structure is composed of a plurality of slow-wave structure rings (4).

3. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claim 2, characterized in that: The outer diameter of the slow-wave structure ring (4) is equal to the inner diameter of the sleeve (5).

4. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claims 1-3, characterized in that: The hollow circular waveguide (2) is coaxial with the sleeve (5).

5. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claim 4, characterized in that: The hollow circular waveguide (2) and the limiting ring (31) are respectively abutted against two ends of the split-type slow-wave structure.

6. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claim 5, characterized in that: When the limiting ring (31) contacts the split slow-wave structure, the slider (32) can slide into the annular groove (12).

7. The high-power microwave generator for facilitating in-situ characterization of breakdown damage traces according to claim 6, characterized in that: An arc-shaped groove (33) is provided on the outer side of the limiting ring (31), and a rotatable arc-shaped pull rod (34) is provided in the arc-shaped groove (33).

8. The method for using a high-power microwave generator for in-situ characterization of breakdown damage traces according to claim 7, characterized in that: The method of use comprises the following steps: Step 1: assembling a plurality of slow-wave structure rings (4) to form a usable Cherenkov type high-power microwave generator; Step 2: Conduct high-power microwave experiments using the assembled Cherenkov-type high-power microwave generator; Step 3: After the high-power microwave experiment, the split slow-wave structure is disassembled; Step 4: placing the slow-wave structure ring (4) on the sample stage of a scanning electron microscope and an energy spectrometer, and performing microscopic morphology characterization based on the scanning electron microscope and the energy spectrometer.

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