Light blocking device for high repetition frequency hard X-ray free electron laser device

Abstract

The utility model provides a light blocking device for a high repetition frequency hard X-ray free electron laser device. Comprising a vacuum chamber assembly, a light blocking assembly located in the vacuum chamber assembly, a vacuum pump connected with the vacuum chamber assembly, a movement mechanism penetrating through the vacuum chamber assembly and driving the light blocking assembly to move up and down, and a support fixedly supported at the bottom of the vacuum chamber assembly. The light blocking assembly comprises CVD diamond, SiC and a burn-through detector which are sequentially arranged in the propagation direction of the free electron laser. According to the light blocking device, the diamond and the SiC which are made of light atomic number materials are adopted as materials for bearing heat loads, specifically, the diamond and the SiC are combined and arranged front and back, the light blocking function is achieved, and the problem that the light blocking material loses efficacy due to the fact that the heat loads of hard X-ray free electron lasers with the repetition frequency being 1 MHz are too high is solved.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of light beam line engineering and free electron laser thermal radiation absorption, specifically relates to a kind of light barrier for high repetition rate hard X-ray free electron laser device, for blocking hard X-ray free electron laser, especially with high brightness, ultra-short pulse, full coherence, high repetition rate high repetition rate hard X-ray free electron laser. BACKGROUND

[0002] SHINE is high repetition rate hard X-ray free electron laser device, with high brightness, ultra-short pulse, full coherence, high repetition rate, energy range wide (0.2~15keV) and other characteristics.The repetition rate of SHINE can reach 1MHz, and total power and peak power density are as high as 2.1kW and 253.1W / urad respectively 2 .

[0003] Photon Shutter is the key element of front-end area equipment protection system and beamline personal protection system, and is one of the core components of beamline.When Photon Shutter is opened, light beam is transported to downstream, and when it is closed, light beam is cut off.In the event of a sudden vacuum accident, Photon Shutter is interlocked with downstream valve, and falls down to block light beam before valve is closed, to protect downstream elements from direct irradiation of light beam;in standby state, Photon Shutter is linked with radiation protection equipment to ensure that staff can safely enter diagnostic area.

[0004] Photon Shutter is the key element of front-end area equipment protection system and beamline personal protection system, and is one of the core components of beamline.The existing Photon Shutter of synchrotron radiation device mainly uses heavy atomic number materials such as oxygen-free copper, chromium-zirconium copper or dispersed oxygen copper as heat load bearing material, and processes cooling water pipeline in the interior, to take out heat through cooling water.The thermal conductivity of these heat load bearing materials can reach 400W / m℃.

[0005] However, considering that hard X-ray free electron laser has the characteristic of high power density, if heavy atomic number material is used as Photon Shutter material for hard X-ray free electron laser, there will be a problem of thermal damage.Heavy atomic number material has larger photoelectric effect and Compton scattering cross section for X-ray, resulting in more energy being absorbed and converted into heat energy.If the thermal conductivity of material is low or heat dissipation is insufficient, local temperature rise may exceed the melting point or thermal stress threshold of material, causing damage. UTILITY MODEL CONTENTS

[0006] The utility model aims at providing a kind of light barrier for high repetition rate hard X-ray free electron laser device, to be used for blocking hard X-ray free electron laser, especially with high brightness, ultra-short pulse, full coherence, high repetition rate high repetition rate hard X-ray free electron laser.

[0007] In order to achieve the above object, the utility model provides a light baffle for high repetition rate hard X ray free electron laser device, including vacuum chamber subassembly, the light baffle component in the inside of vacuum chamber subassembly, the vacuum pump being connected with vacuum chamber subassembly, the moving mechanism being driven the light baffle component up and down movement through the vacuum chamber subassembly, and the support fixed in the bottom of vacuum chamber subassembly's support, the light baffle component includes the CVD diamond, SiC and burn through detector in turn along the propagation direction of free electron laser arrangement.

[0008] The burn through detector is used for real time monitoring the failure condition of upstream CVD diamond and SiC, and interlocks with the vacuum valve upstream and downstream of the light baffle and the electron gun for outputting electron beam current, so as to drive the electron beam current to be rejected when detecting the failure of CVD diamond and SiC of the light baffle, while closing the vacuum valve upstream and downstream of the light baffle.

[0009] The CVD diamond and SiC are connected with the water cooling assembly penetrating the vacuum chamber subassembly.

[0010] The CVD diamond and SiC of the light baffle component all include the working position light blocking part and the moving position light blocking part which are spaced apart and fixed in position, the working position light blocking part of CVD diamond and SiC is embedded in the inside of the water cooling assembly, for blocking the light beam when the light baffle component is in the lower position, the lower position is the working position, the moving position light blocking part of CVD diamond and SiC is fixed on the surface of the water cooling assembly facing upstream, for preventing the light beam from irradiating the surface of the water cooling assembly below the light baffle component when the light baffle component moves from the lower position to the upper position.

[0011] The moving position light blocking part of the CVD diamond is rectangular with a circular hole in at least one part, the outer dimension is 31*20*2mm, and the circular hole size is Φ14; the working position light blocking part is circular, the size is Φ21*4mm; the moving position light blocking part of the SiC is rectangular with a circular hole in at least one part, the outer dimension is 31*20*10mm, and the circular hole size is Φ14; the working position light blocking part is circular, the size is Φ30*10mm.

[0012] The water cooling assembly includes a water cooling copper seat, a blocking ring and a water cooling jacket inside the vacuum chamber subassembly, the CVD diamond and SiC are embedded at the two limiting steps in the through hole of the water cooling copper seat, and the blocking ring is arranged between the CVD diamond and SiC in the through hole of the water cooling copper seat; the water cooling jacket is sleeved outside the water cooling copper seat and cooperates with the water cooling copper seat to define a cooling water cavity for heat exchange, the water cooling jacket is fixed with a cooling water pipe in communication with the cooling water cavity, and the cooling water pipe is filled with cooling water.

[0013] The material of the water-cooled copper seat and the blocking ring is oxygen-free copper; the water-cooled copper seat and the blocking ring, the water-cooled copper seat and the water-cooled jacket, the water-cooled copper seat and the CVD diamond, the water-cooled jacket and the cooling water pipe, and the blocking ring and the CVD diamond are fixedly connected by brazing or argon arc welding; and the gold foil is arranged between the water-cooled copper seat and the SiC.

[0014] The cooling water pipe is externally sleeved with a bellows, the bellows and the cooling water pipe are communicated with the atmosphere, and at least part of the outside of the bellows is located inside the vacuum chamber assembly.

[0015] The SiC and the burn-through detector are provided with a photodiode.

[0016] The burn-through detector comprises a helium container with a through hole and two vacuum flanges arranged at two ends of the helium container to block the through hole, so as to jointly define a helium cavity by the helium container and the vacuum flanges.

[0017] The light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model adopts light atomic number material diamond and SiC material to replace the existing oxygen-free copper, chrome-zirconium copper or dispersed oxygen copper and other heavy atomic number materials as the material for bearing heat load, and the diamond and SiC are arranged before and after the specific use, the light blocking function is realized, the problem that the hard X-ray free electron laser with a repetition frequency of 1MHz has too high thermal load to cause the failure of the light blocking material is solved, the laser energy range of 0.2-25keV is covered, and the highest central high heat load of 2500W / mm 2 Can be handled. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the principle schematic view of the light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model.

[0019] Figures 2A-2C It is the structure schematic view of the light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model, wherein Figure 2A The overall structure is shown, Figure 2B And Figure 2C The structure view of different perspectives of the remaining parts after the self and the vacuum chamber assembly are removed is shown.

[0020] Figure 3 It is the cross-sectional view of the mounting mode of the light blocking assembly and the water cooling assembly of the light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model.

[0021] Figure 4 It is the cross-sectional view of the mounting mode of the light blocking assembly and the water cooling assembly of the light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model. DETAILED DESCRIPTION

[0022] The utility model will be further explained in combination with specific embodiments. It should be understood that the following embodiments are only used to illustrate the utility model and are not used to limit the scope of the utility model.

[0023] The light blocker for the high-repetition-rate hard X-ray free electron laser device is based on the following principles:

[0024] The single pulse energy of the free electron laser is as high as several muJ to several mJ, which requires the light blocker to select ultra-high vacuum materials with low atomic number and small radiation damage. CVD diamond, boron carbide B4C and SiC materials are commonly used light atomic number materials.

[0025] At the same time, due to the extremely high peak power density and high total power of the high-repetition-rate hard X free electron laser, the light blocker must select materials with good heat conduction performance. The thermal conductivity of B4C is only 50 W / m·K, and even if the grazing incidence method is used, it cannot meet the use requirements.

[0026] The utility model uses light atomic number materials such as diamond and SiC materials to replace the existing heavy atomic number materials such as oxygen-free copper, chromium-zirconium copper or dispersed copper oxide as the material for bearing heat load, and specifically uses CVD (Chemical Vapor Deposition) diamond and SiC material combination to block light, which is suitable for the light blocker of the high-repetition-rate hard X-ray free electron laser device such as SHINE light blocker.

[0027] Among them, the main element of diamond is C, the thermal damage problem is small, and the thermal conductivity can usually reach 1500 W / m℃. Diamond film is usually made by thermal deposition method, which has small density but is difficult to make thick. Sintered SiC is a good thermal conductive material with low price, so the utility model uses diamond and SiC combination before and after to arrange and realize the light blocking function to avoid the problem of material thermal damage as much as possible. Therefore, when the hard X-ray free electron laser device is working normally, the light blocker is opened, the light beam is transported to the downstream, and the light beam is cut off when the light blocker is closed; in the event of a sudden vacuum accident, the light blocker is interlocked with the downstream valve, and the light blocker blocks the light beam before the downstream vacuum valve is closed, protecting the downstream elements from direct irradiation of the light beam; in standby state, the light blocker is linked with the radiation protection equipment to ensure the safety of the staff entering the diagnosis area.

[0028] In addition, the burn-through detector of the light blocker for the high-repetition-rate hard X-ray free electron laser device is interlocked with vacuum valves upstream and downstream of the light blocker and an electron gun for outputting an electron beam current, so as to drive the electron beam current to be rejected when the CVD diamond 10 and the SiC 20 of the light blocker are detected to fail, and simultaneously close the vacuum valves upstream and downstream of the light blocker.

[0029] Figure 1 is a schematic diagram of the principle of the light blocker for the high-repetition-rate hard X-ray free electron laser device of the utility model. Figure 1 As shown in the figure, the light blocker for the high-repetition-rate hard X-ray free electron laser device comprises CVD diamond 10, SiC 20 (silicon carbide) and burn-through detector 30 (BTM, Burn Through Monitor) arranged in sequence along the propagation direction of the free electron laser (FEL). Among them, the CVD diamond 10 is mainly used for absorbing low-energy photons; the SiC 20 is used for absorbing high-energy photons; the burn-through detector 30 is used for monitoring the failure condition of the CVD diamond 10 and the SiC 20 upstream in real time, and is interlocked with the vacuum valves upstream and downstream of the light blocker and the electron gun for outputting the electron beam current, so as to drive the electron beam current to be rejected when the CVD diamond 10 and the SiC 20 of the light blocker are detected to fail, and simultaneously close the vacuum valves upstream and downstream of the light blocker.

[0030] Among them, the electron beam current is injected by the electron gun, and driving the electron beam current to be rejected means that the electron gun stops injecting the electron beam current. Specifically, through the PLC (programmable controller) system, a switching quantity is given to the operation control system of the accelerator, so as to achieve the effect of driving the electron gun to stop injecting the electron beam current.

[0031] The vacuum valves upstream and downstream of the light blocker are closed, which is used for preventing the burn-through detector 30 from being punched, so as to cause helium gas to leak into the vacuum systems upstream and downstream of the light blocker. Specifically, the burn-through detector 30 will be internally filled with helium before installation, because the vacuum system is more sensitive to the detection of helium, if the BTM is punched, helium will leak into the vacuum system, therefore, it is necessary to close the vacuum valves upstream and downstream of the light blocker in time, so as to prevent the helium leakage from causing damage to the vacuum systems upstream and downstream of the light blocker.

[0032] As shown in the figure, Figures 2A-2C The light blocker comprises a vacuum chamber assembly 40, a light blocking assembly located inside the vacuum chamber assembly 40, a vacuum pump connected with the vacuum chamber assembly 40, a movement mechanism 50 penetrating through the vacuum chamber assembly 40 and driving the light blocking assembly to move up and down, and a support 60 supported and fixed to the bottom of the vacuum chamber assembly 40.

[0033] The light blocking assembly is the core of the light blocker, and includes CVD diamond 10, SiC 20 and burn-through detector 30 arranged in sequence along the propagation direction of the free electron laser.

[0034] The support 60 is used for supporting and fixing the vacuum chamber assembly 40.

[0035] The light blocking assembly is fixed at the moving end of the motion mechanism 50 to move up and down with the moving end of the motion mechanism 50. When the light blocking assembly is in the upper position, the light beam is transported to the downstream; when the light blocking assembly is in the lower position (i.e. the working position), the light beam is cut off.

[0036] The vacuum chamber assembly 40 is used for ensuring smooth transmission of the high-repetition-rate hard X free electron laser, so that all devices in the beamline part operate inside the vacuum system. The vacuum chamber assembly 40 is generally made of a stainless steel cavity welded, and has vacuum flanges at the upstream and downstream and the side edges, which are used for installation of a vacuum pump such as an ion pump, connection of upstream and downstream vacuum devices, feeding of temperature control devices inside and outside the vacuum, or feeding of a moving part.

[0037] The CVD diamond 10 and SiC 20 of the light blocking assembly inside the vacuum chamber assembly 40 are connected with a water cooling assembly penetrating through the vacuum chamber assembly 40 to realize cooling of the light blocking assembly. Figure 3 and Figure 4 The installation mode of the light blocking assembly and the water cooling assembly is shown. As shown in Figure 3 and Figure 4 The water cooling assembly includes a water-cooled copper seat 71, a blocking ring 72 and a water-cooled jacket 73 inside the vacuum chamber assembly 40, the CVD diamond 10 and SiC 20 are embedded at two limiting steps in the through hole of the water-cooled copper seat 71, the blocking ring 72 is arranged at a position between the CVD diamond 10 and SiC 20 in the through hole of the water-cooled copper seat 71; the water-cooled jacket 73 is sleeved outside the water-cooled copper seat 71 and cooperates with the water-cooled copper seat 71 to define a cooling water cavity for heat exchange, the water-cooled jacket 73 is fixed with a cooling water pipe 74 in communication with the cooling water cavity, and the cooling water pipe 74 is filled with cooling water.

[0038] In the embodiment, the materials of the water-cooled copper seat and the blocking ring are oxygen-free copper. The water-cooled copper seat 71 plays a role of heat exchange and serves as a heat conductor of the diamond and SiC; the blocking ring 72 is used for crimping and fixing the diamond, and is welded on the CVD diamond 10 by brazing in the processing process, and further helps heat conduction of the CVD diamond 10 at the back

[0039] The water-cooled copper seat 71 and the blocking ring 72, the water-cooled copper seat 71 and the water-cooled jacket 73, the water-cooled copper seat 71 and the CVD diamond 10, the water-cooled jacket 73 and the cooling water pipe 74, and the blocking ring 72 and the CVD diamond 10 are fixedly connected by brazing or argon arc welding. The leakage rate between the water-cooled copper seat 71 and the water-cooled jacket 73 and between the water-cooled jacket 73 and the cooling water pipe 74 is less than 1×10-6Torr.L / s. -12 Torr.L / s.

[0040] The welding between the CVD diamond 10 and the water-cooled copper seat 71 and the blocking ring 72 is to maintain the heat transfer and fixation of the CVD diamond 10, and brazing can be used for the connection.

[0041] The water-cooled copper seat 71 and the water-cooled jacket 73 can be connected by brazing to define a sealed cooling water cavity therebetween; and the water-cooled jacket 73 and the cooling water pipe 74 are connected by argon arc welding to ensure the sealing connection of the water path. The two weldings are to prevent the water in the cooling water pipe 74 from leaking into the vacuum environment where the light-blocking assembly is located.

[0042] A gold foil is arranged between the water-cooled copper seat 71 and the SiC 20. The gold foil is arranged to improve the contact area between the water-cooled copper seat 71 and the SiC 20 and increase the heat conduction. In the embodiment, the water-cooled system adopts single-circulation water cooling, and therefore the cooling water pipe 74 includes a water inlet pipe and a water outlet pipe, and the cooling water is introduced from the water inlet pipe and discharged from the water outlet pipe.

[0043] In the embodiment, the inner diameter of the cooling water pipe 74 is Φ8mm, and the outer diameter is Φ10mm; the working pressure of the cooling water in the cooling water pipe 74 is 6-8kg / cm 2 , and the cooling water flow is 6-8L / min.

[0044] To ensure the sealing performance, the water passage weld 78 between the water-cooled copper seat 71 and the water-cooled jacket 73 is subjected to a 10kg / cm 2 pressure holding test for 1 hour.

[0045] Please also refer to Figure 2C , Figure 3 , Figure 4 The cooling water pipe 74 is externally sleeved with a corrugated pipe 75, the corrugated pipe 75 and the cooling water pipe 74 are in communication with the atmosphere, and at least a part of the outside of the corrugated pipe 75 is located inside the vacuum chamber assembly 40. Therefore, the outside of the corrugated pipe is in vacuum, the cavity between the inside of the corrugated pipe and the water pipe is in atmosphere, and the sealing joint between the water and the vacuum is in the atmosphere. Even if the water pipe leaks, it is directly in the atmosphere and does not directly enter the vacuum, so that the water pipe does not directly leak in the vacuum when leaking.

[0046] In the embodiment, the bellows 75 is connected to the water-cooled copper seat 71 through a CF16 flange 76.

[0047] The CVD diamond 10 and the SiC 20 of the light blocking assembly each include two light blocking parts spaced apart from each other and fixed in position, one being a working position light blocking part and the other being a moving position light blocking part. The working position light blocking parts of the CVD diamond 10 and the SiC 20 are embedded inside the water-cooled copper seat 71 of the water-cooled assembly and used to block the light beam when the light blocking assembly is in the lower position (i.e. the working position); the moving position light blocking parts of the CVD diamond 10 and the SiC 20 are fixed on the surface of the water-cooled assembly facing the upstream and used to prevent the light beam from irradiating on the water-cooled assembly (such as the water-cooled copper seat 71, the blocking ring 72 and the water-cooled jacket 73) below the light blocking assembly when the light blocking assembly moves from the lower position to the upper position.

[0048] In the embodiment, the working position light blocking part is located downstream along the propagation direction of the free electron laser, and the moving position light blocking part is located upstream along the propagation direction of the free electron laser, thereby achieving light blocking of the water-cooled assembly.

[0049] According to the design aperture, the light blocker of the working position light blocking part can be divided into Φ14 light blocker, Φ25 light blocker, Φ38 light blocker and Φ76 light blocker, and the working principles and cooling modes of the four types of light blockers are completely the same. Here, the Φ14 light blocker with the highest thermal load, the closest distance to the accelerator and the relatively low cost will be described as an example.

[0050] In the embodiment, the moving position light blocking part of the CVD diamond 10 has a cross section of at least a part of a rectangle with a circular hole, and the outer dimensions are 31x20x2mm, and the size of the circular hole is Φ14; the cross section of the working position light blocking part is circular, and the size is Φ21x4mm. The moving position light blocking part of the SiC 20 has a cross section of at least a part of a rectangle with a circular hole, and the outer dimensions are 31x20x10mm, and the size of the circular hole is Φ14; the cross section of the working position light blocking part is circular, and the size is Φ30x10mm.

[0051] As shown in Figure 3 and Figure 4 A photodiode 80 can also be provided between the SiC 20 and the burn-through detector 30, and the photodiode 80 and the burn-through detector 30 are simultaneously interlocked with the vacuum valves upstream and downstream of the light blocker and the electron gun for outputting the electron beam current, so as to form a double-monitored interlocking protection system.

[0052] The photodiode is fixed on one side surface of the SiC 20.

[0053] The working principle of the burn-through detector 30 is that, because the vacuum chamber assembly 40 is sensitive to helium detection, if the burn-through detector 30 is punctured, helium will leak into the vacuum chamber assembly 40 to be detected, at which time the upstream and downstream valves need to be closed in time to prevent the helium leakage from damaging the vacuum system of the upstream and downstream equipment. The helium detection is completed by the quadrupole leak detector of the vacuum chamber assembly 40.

[0054] Please also refer to Figure 2A The movement mechanism 50 mainly comprises a gas cylinder 51, a guide column 52, a linear bearing 53, etc., the moving end of the movement mechanism is connected with the light blocking assembly to simultaneously drive the two sets of CVD diamond 10 and SiC 20 and the burn-through detector 30 to simultaneously perform lifting movement. The gas cylinder is fixed on the base and drives the moving end of the movement mechanism to move linearly along the guide column, and the moving end forms a low-friction sliding pair with the guide column through the linear bearing. In this embodiment, the movement mechanism is a general type, wherein the type of the gas cylinder is CQ2YA100-65DCMZ_0, and the type of the linear bearing is 00050337.

[0055] The light blocking material is arranged before and after the combination of the diamond and the SiC, the light blocking function is realized, the problem that the light blocking material fails due to too high thermal load of the hard X-ray free electron laser with a repetition frequency of 1MHz is solved, the laser energy range of 0.2-25keV is covered, and the highest central high thermal load of 2500W / mm 2 can be handled.

[0056] The above is only a preferred embodiment of the utility model, and is not used to limit the range of the utility model, and the above embodiment of the utility model can be variously changed. Simple, equivalent changes and modifications made according to the content of the claims and the specification of the utility model application all fall into the protection range of the claims of the utility model patent. The utility model is not described in detail, and is conventional technical content.

Claims

1. A beam deflector for a high-repetition-rate hard X-ray free-electron laser device, characterized in that, It includes a vacuum chamber assembly, a light-blocking assembly located inside the vacuum chamber assembly, a vacuum pump connected to the vacuum chamber assembly, a motion mechanism that passes through the vacuum chamber assembly and drives the light-blocking assembly to move up and down, and a bracket that supports and is fixed to the bottom of the vacuum chamber assembly. The light-blocking assembly includes CVD diamond, SiC, and a burn-through detector arranged sequentially along the propagation direction of the free electron laser.

2. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 1, characterized in that, The burn-through detector is used to monitor the failure status of the upstream CVD diamond and SiC in real time, and is interlocked with the vacuum valves upstream and downstream of the light blocker and the electron gun for outputting the electron beam current, so as to drive the rejection of the electron beam current when the failure of the CVD diamond and SiC of the light blocker is detected, and at the same time close the vacuum valves upstream and downstream of the light blocker.

3. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 1, characterized in that, Both the CVD diamond and SiC are connected to the water-cooling assembly that runs through the vacuum chamber assembly.

4. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 3, characterized in that, The CVD diamond and SiC of the light-blocking component each include a working position light-blocking part and a moving position light-blocking part that are spaced apart from each other and fixed in relative position. The working position light-blocking part of the CVD diamond and SiC is embedded inside the water-cooling component and is used to block the light beam from passing through when the light-blocking component is in the lower position, which is the working position. The moving position light-blocking part of the CVD diamond and SiC is fixed on the upstream-facing surface of the water-cooling component and is used to prevent the light beam from shining on the surface of the water-cooling component below the light-blocking component when the light-blocking component moves from the lower position to the upper position.

5. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 4, characterized in that, The cross-section of the moving position light-blocking part of the CVD diamond is a rectangle with at least a portion having a circular hole, and its external dimensions are 31×20×2mm, with the circular hole size being Φ14; the cross-section of the working position light-blocking part is circular, with dimensions of Φ21×4mm. The cross-section of the moving position light-blocking part of the SiC is a rectangle with at least a portion having a circular hole, and its external dimensions are 31×20×10mm, with the circular hole having a size of Φ14; the cross-section of the working position light-blocking part is circular, with a size of Φ30×10mm.

6. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 3, characterized in that, The water-cooling assembly includes a water-cooled copper base, a retaining ring, and a water-cooled jacket located inside the vacuum chamber assembly. The CVD diamond and SiC are embedded in two limiting steps within the through hole of the water-cooled copper base. The retaining ring is located within the through hole of the water-cooled copper base between the CVD diamond and SiC. The water-cooled jacket is fitted over the water-cooled copper base and together with the water-cooled copper base defines a cooling water cavity for heat exchange. A cooling water pipe communicating with the cooling water cavity is fixed on the water-cooled jacket, and the cooling water pipe is filled with cooling water.

7. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 6, characterized in that, The water-cooled copper base and retaining ring are made of oxygen-free copper. The water-cooled copper base and the retaining ring, the water-cooled copper base and the water-cooled outer jacket, the water-cooled copper base and the CVD diamond, the water-cooled outer jacket and the cooling water pipe, and the retaining ring and the CVD diamond are all fixedly connected by brazing or argon arc welding. A gold foil is placed between the water-cooled copper base and the SiC.

8. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 6, characterized in that, The cooling water pipe is fitted with a corrugated pipe, which is in communication with the atmosphere, and at least a portion of the outer side of the corrugated pipe is located inside the vacuum chamber assembly.

9. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 1, characterized in that, A photodiode is provided between the SiC and the burn-through detector.

10. The beam deflector for a high-repetition-rate hard X-ray free-electron laser device according to claim 1, characterized in that, The burn-through detector includes a helium container with a through hole and two vacuum flanges located at both ends of the helium container to seal the through hole, so that the helium container and the vacuum flanges together define a helium cavity.

Images