A clamping device resistant to ultra-high temperatures and its application

Abstract

This invention relates to a high-temperature resistant clamping device and its application, belonging to the field of performance testing technology for electron emission cooling materials. Existing conventional clamping devices suffer from defects such as material shifting, device tipping, and inability to provide a bias electric field under ultra-high temperature conditions, making it difficult to meet testing requirements. This invention provides a high-temperature resistant clamping device comprising a cathode section and an anode section; wherein the cathode section includes a bias cathode conductive plate, a bias cathode conductive support cylinder, a detachable conductive outer shell, an insulating ceramic sleeve, a split-type Joule heating sleeve, an insulating ceramic strip, and an insulating ceramic fixing post. The clamping device provided by this invention supports multiple heating modes, can flexibly change the material potential, and can maintain clamping stability under extreme conditions of ultra-high temperature and applied bias electric field; combined with a matching high-pressure vacuum test chamber and testing methods, it can test various properties of electron emission materials under actual service conditions.

Description

Technical Field

[0001] This invention relates to the field of performance testing technology for electron escape cooling materials, and in particular to a clamping device resistant to ultra-high temperatures and its application. Background Technology

[0002] Electron emission cooling materials are a promising new type of thermal protection material. Accurate, rapid, and simultaneous detection and analysis of their thermoelectric emission properties, electron emission cooling properties, and temperature resistance are crucial prerequisites for developing high-performance electron emission cooling materials. Specifically, thermoelectric emission properties are typically analyzed based on the material's thermoelectric emission curve; electron emission cooling properties are currently mainly assessed by indirectly determining the material's electron emission capability through work function testing, thereby analyzing its electron emission cooling performance; temperature resistance primarily characterizes the material's stability at high temperatures (e.g., melting point), while ablation resistance involves characteristics such as the center ablation retreat rate.

[0003] However, currently, there is no mature testing device for simultaneous analysis of electron-evolving materials used in environments above 2000℃. Existing methods for testing the basic electron-evolving cooling performance, heat resistance, and thermoelectric properties of electron-evolving cooling materials are mostly based on relatively independent analytical tests. Such methods often cannot perform online testing based on the actual service conditions of the materials, and cannot obtain real-time data on the true material performance under the synergistic influence of the multimodal properties of electron-evolving materials. Furthermore, in high vacuum and ultra-high temperature environments, the clamping and fixing devices for electron-evolving materials often experience slippage and displacement due to differences in thermal expansion coefficients under the influence of gravity, which is a significant factor affecting the accuracy of material performance testing. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a clamping device resistant to ultra-high temperatures and its application, in order to solve at least one of the defects of existing conventional clamping devices under ultra-high temperature conditions, such as material shift, device tilting, and inability to provide a bias electric field.

[0005] The present invention provides a clamping device resistant to ultra-high temperature, the clamping device comprising a cathode part and an anode part;

[0006] The cathode section includes a biased cathode conductive plate 1, a biased cathode conductive support cylinder 2, a detachable conductive outer shell 3, an insulating ceramic sleeve 11, a split Joule heating sleeve, an insulating ceramic strip 13, and an insulating ceramic fixing column 6.

[0007] The split-type Joule heating sleeve includes a first semi-annular sleeve 14 and a second semi-annular sleeve 15; an insulating ceramic strip 13 is provided between the mating edges of the first semi-annular sleeve 14 and the second semi-annular sleeve 15, and there are a total of 2 insulating ceramic strips 13.

[0008] The corresponding positions on the inner walls of the first semi-annular sleeve 14 and the second semi-annular sleeve 15 and one end of the insulating ceramic fixing post 6 are provided with fastening threads 17, which are used to fix the insulating ceramic fixing post 6 in the inner cavity of the split Joule heating sleeve by screwing in.

[0009] The end face of the insulating ceramic fixing post 6 with the fastening thread 17 and the inner wall of the split Joule heating sleeve together form the sample receiving cavity 16.

[0010] The split-type Joule heating sleeve is provided with an insulating ceramic sleeve 11 on the outside;

[0011] The insulating ceramic sleeve 11 is provided with an offset cathode conductive support cylinder 2 and a detachable conductive outer shell 3 on the outside. The offset cathode conductive support cylinder 2 and the detachable conductive outer shell 3 together form a complete cylindrical structure and match the shape of the outer wall of the insulating ceramic sleeve 11.

[0012] The biased cathode conductive support cylinder 2 is provided with an annular biased cathode conductive plate 1 on its outside.

[0013] The biased cathode conductive plate 1, the biased cathode conductive support cylinder 2, the insulating ceramic sleeve 11, and the split Joule heating sleeve are coaxially nested and installed with their end faces away from the insulating ceramic column flush with each other.

[0014] Optionally, the end face of the insulating ceramic fixing post 6 with the fastening thread 17 is provided with a heat insulation pad 18 and a protective plate 19 in sequence.

[0015] Specifically, the bias cathode conductive plate 1 is 3-8 mm thick.

[0016] Specifically, the biased cathode conductive plate 1, the biased cathode conductive support cylinder 2, and the detachable conductive outer shell 3 are electrically connected; the biased cathode conductive plate 1 or the biased cathode conductive support cylinder 2 is provided with a biased cathode conductive terminal 8.

[0017] Specifically, the detachable conductive outer shell 3 and the insulating ceramic sleeve 11 are provided with fastening through holes at corresponding positions, and the first semi-annular sleeve 14 is provided with fastening grooves at corresponding positions. The through holes and grooves are used to set fastening screws, thereby achieving accurate positioning and firm connection of the first semi-annular sleeve 14 and the second semi-annular sleeve 15.

[0018] Specifically, the detachable conductive housing 3 is provided with an assembly through hole, and the biased cathode conductive support cylinder 2 is provided with an assembly groove at a corresponding position, for tightly connecting the detachable conductive housing 3 and the biased cathode conductive support cylinder 2 with bolts.

[0019] Specifically, the biased cathode conductive plate 1, the biased cathode conductive support cylinder 2, the detachable conductive outer shell 3, and the split Joule heating sleeve are made of one or more of the following materials: tungsten, molybdenum, titanium, refractory metal alloy, high-purity graphite, carbide ceramic, boride ceramic, or nitride ceramic.

[0020] The insulating ceramic sleeve 11, insulating ceramic strip 13, and insulating ceramic fixing post 6 are made of one or more of the following: boride, carbide, or nitride insulating ceramics.

[0021] Specifically, the protective plate 19 is made of one or more of the following materials: tungsten, molybdenum, refractory metals and alloys, high-purity alumina ceramics, boron nitride ceramics, and zirconium oxide ceramics; the thickness of the protective plate 19 is 1-5 mm.

[0022] Specifically, the sample receiving cavity 16 is filled with a flexible conductive material for loading and fixing irregularly shaped test samples.

[0023] The present invention also discloses an electron evaporation cooling material performance testing device, the device including the above-mentioned clamping device;

[0024] The equipment also includes a high vacuum test chamber, a heating module, a pressure control module, a power supply and current detection module, a temperature and surface morphology detection module, and a host computer control module.

[0025] This invention also discloses a method for testing the performance of electron evaporation cooling materials. The testing method uses the aforementioned testing equipment and specifically includes the following steps:

[0026] Step 1: Install the sample to be tested on the sample clamping device. When laser heating, assemble the heat insulation pad 18 and the protective plate 19. When Joule heating, only use the split Joule heating sleeve to form a current loop with the sample to be tested. Close the high vacuum test chamber.

[0027] Step 2: Adjust the chamber pressure to below 1×10-4 Pa using the pressure control module, circulate inert gas for gas replacement, and preheat to above 300°C under a stable pressure of 1×10-4 Pa.

[0028] Step 3: The heating module raises the temperature, and a gradient strategy is used to control the heating rate.

[0029] When the temperature difference is greater than 1000℃, the heating rate should be ≤50℃ / min.

[0030] When the temperature difference is 200–1000℃, the heating rate should be ≤40℃ / min.

[0031] When the temperature difference is <200℃, the heating rate is ≤20℃ / min;

[0032] Step 4: The thermoelectric emission performance, cooling performance, temperature resistance performance and ablation resistance performance of the sample are jointly detected by the power supply and current detection module and the temperature and surface morphology detection module.

[0033] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0034] 1. The ultra-high temperature resistant clamping device provided by the present invention achieves stable clamping in an ultra-high temperature vacuum environment through structural design and material selection. It is applicable to temperatures not lower than 2000℃ and supports Joule heating, laser heating and other modes, and can provide a bias electric field.

[0035] In the performance testing of electron-evolving materials, it is necessary to test the material's thermoelectric emission performance, electron emission cooling performance, and heat resistance. Performance testing of electron-evolving materials typically employs methods such as laser heating and Joule heating. Laser heating, in particular, requires the material to maintain an absolutely consistent position; any change in the material's position may alter the heating location or cause emission deviation in the optical path, leading to safety hazards. Therefore, the material under test must be able to maintain its relative displacement at high temperatures. During high-temperature experiments, the clamping device provided by this invention incorporates multiple layers of fixing devices, effectively preventing relative displacement of components caused by differences in the thermal expansion coefficients of different materials. For example, after assembly, the biased cathode conductive support cylinder, detachable conductive shell, insulating ceramic sleeve, split Joule heating sleeve, insulating ceramic strip, and insulating ceramic fixing post form a robust whole under the locking of assembly bolts, fastening bolts, and fastening threads. Even if there are certain differences in the thermal expansion coefficients of the components, relative displacement will not occur at high temperatures, preventing displacement of the clamped sample.

[0036] Furthermore, when Joule heating is used on the material, the clamping device needs to have independent positive and negative electrodes to perform Joule heating on the electron-evolving material. Additionally, when testing the performance of the electron-evolving material, this heating process typically requires applying a bias voltage between the outer wall surface of the material and the anode. Therefore, the positive and negative electrodes in the clamping device that apply Joule heating to the electron-evolving material need to be independent of the bias voltage field on the material wall surface and not interfere with each other. Therefore, this invention provides an insulating ceramic layer (mainly referring to an insulating ceramic sleeve) outside the positive and negative electrodes used for Joule heating of the electron-evolving material to isolate the outer bias voltage applied to the electron-evolving material from the outer shell.

[0037] The clamping device provided by this invention supports both Joule heating mode and laser heating mode.

[0038] 2. The clamping device cavity provided by this invention is applicable to test materials of different shapes, unaffected by material size, and can be used for targeted testing of irregularly shaped materials. It is worth noting that when testing irregularly shaped materials, the cavity needs to be filled with a flexible conductive material to prevent material slippage.

[0039] 3. The electron emission cooling material performance testing equipment and supporting testing methods provided by this invention are suitable for joint testing of electron emission cooling materials under extreme environments, and the measured performance parameters are closer to the material performance under actual working conditions.

[0040] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0041] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0042] Figure 1 This is a schematic diagram of the overall structure of the cathode section of a clamping device resistant to ultra-high temperatures;

[0043] Figure 2 This is a top view schematic diagram of the overall structure of the cathode section of a clamping device resistant to ultra-high temperatures;

[0044] Figure 3 This is a side view schematic diagram of the partial structure and assembly relationship of the insulating ceramic sleeve at the cathode of a clamping device resistant to ultra-high temperatures;

[0045] Figure 4 This is a side view schematic diagram of the partial structure and assembly relationship of a three-dimensional Joule heating sleeve for the cathode part of a clamping device resistant to ultra-high temperature.

[0046] Figure 5 This is a cross-sectional schematic diagram of the overall structure of the cathode section of a clamping device resistant to ultra-high temperatures;

[0047] Figure 6 This is a schematic diagram of a possible anode structure;

[0048] Figure 7 This is a possible cross-sectional view of the anode structure.

[0049] Figure label:

[0050] 1. Biased cathode conductive plate; 2. Biased cathode conductive support cylinder; 3. Removable conductive outer shell; 4. First fastening through hole; 5. First semi-annular sleeve conductive terminal; 6. Insulating ceramic fixing post; 7. Second semi-annular sleeve conductive terminal; 8. Biased cathode conductive terminal; 9. First assembly through hole; 10. Second assembly through hole; 11. Insulating ceramic sleeve; 12. Second fastening through hole; 13. Insulating ceramic strip; 14. First semi-annular sleeve; 15. Second semi-annular sleeve; 16. Sample receiving cavity; 17. Fastening thread; 18. Heat insulation pad; 19. Protective plate;

[0051] 20. Plasma-excited anode plate; 21. Conductive terminal of anode plate; 22. Anode insulating ceramic retaining ring; 23. Anode metal support ring; 24. Conductive terminal of anode metal support ring; 25. Anode ceramic support column. Detailed Implementation

[0052] Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0053] The clamping device provided by this invention can withstand laser heating and ultra-high temperature heating environments, and can realize functions such as Joule heating and material wall bias voltage regulation. Moreover, the internal structure can avoid slippage and misalignment problems caused by the difference in thermal expansion coefficients of different materials. It is suitable for extreme testing environments above 2000℃, and is especially suitable for comprehensive performance testing of electron-evolving materials under ultra-high temperature vacuum environment.

[0054] Currently, there are no publicly available reports on the performance testing of electron-emission materials under extreme environments. Through theoretical research and experimental exploration, the R&D team has identified the following difficulties or urgent technical problems and proposed possible solutions:

[0055] (1) In the performance testing of electron-evolving materials, it is necessary to test the thermoelectric emission performance, electron emission cooling performance, and heat resistance performance of the materials. Performance testing of electron-evolving materials typically employs methods such as laser heating and Joule heating. Laser heating, in particular, requires the material to maintain an absolutely consistent position. If the material's position changes, it may alter the heating position or cause the optical path to shift, leading to safety hazards. Therefore, the material under test must be able to maintain its relative displacement at high temperatures. Furthermore, when using Joule heating, the clamping device needs to have independent positive and negative electrodes to perform Joule heating on the electron-evolving material. In addition, when testing the performance of electron-evolving materials, this heating process usually requires applying a bias voltage between the outer wall surface of the material and the anode. Therefore, the positive and negative electrodes in the clamping device that apply Joule heating to the electron-evolving material need to be independent of the bias voltage field on the material wall surface and not interfere with each other. Therefore, the positive and negative electrodes used for Joule heating of the electron-evolving material in this invention require an insulating ceramic layer to isolate the outer bias voltage applied to the electron-evolving material.

[0056] (2) In order to prevent the components from being in a relative state due to the difference in thermal expansion coefficients between different materials during the high-temperature experiment, multiple layers of fixing devices need to be installed inside the device.

[0057] The present invention provides a clamping device resistant to ultra-high temperature, the clamping device comprising a cathode part and an anode part;

[0058] The cathode section includes a biased cathode conductive plate, a biased cathode conductive support cylinder, a detachable conductive outer shell, an insulating ceramic sleeve, a split Joule heating sleeve, an insulating ceramic strip, an insulating ceramic fixing column, a protective plate, and a heat insulation pad.

[0059] The split-type Joule heating sleeve includes a first semi-annular sleeve and a second semi-annular sleeve; an insulating ceramic strip is provided between the mating edges of the first semi-annular sleeve and the second semi-annular sleeve, and there are a total of 2 insulating ceramic strips;

[0060] The insulating ceramic fixing post is cylindrical, made of insulating and high-temperature resistant ceramic, and has a length of 8-15cm, preferably 10cm, to ensure that it can isolate the heat of the clamping device.

[0061] The first semi-annular sleeve, the inner wall of the second semi-annular sleeve, and one end of the insulating ceramic fixing post are provided with fastening threads, which are used to fix the insulating ceramic fixing post in the inner cavity of the split Joule heating sleeve by screwing in.

[0062] Furthermore, the thread pitch ranges from 2 to 5 mm, the nominal diameter ranges from 30 to 50 mm, and the effective engagement length of the thread pitch is from 20 to 40 mm to ensure connection strength.

[0063] The insulating ceramic fixing post has an end face with a fastening thread and the inner wall of the split Joule heating sleeve together to form a sample receiving cavity.

[0064] The outer walls of the first and second semi-annular sleeves are provided with conductive terminals for heating.

[0065] The split-type Joule heating sleeve is externally provided with an insulating ceramic sleeve;

[0066] The insulating ceramic sleeve has a wall thickness of 1 to 5 mm, preferably 3 mm, to isolate the Joule heating positive and negative electrodes from the bias cathode conductive panel, ensuring that the bias voltage field and the Joule heating current do not interfere with each other.

[0067] The insulating ceramic sleeve is provided with a biased cathode conductive support cylinder and a detachable conductive outer shell. The biased cathode conductive support cylinder and the detachable conductive outer shell together form a complete cylindrical structure that matches the shape of the outer wall of the insulating ceramic sleeve.

[0068] The detachable conductive outer shell is a semi-enclosed structure, which is connected to the biased cathode conductive support cylinder by bolts and built-in nuts. The central angle range corresponding to the semi-enclosed structure is 60 to 270°, preferably 180°.

[0069] The biased cathode conductive support cylinder is provided with an annular biased cathode conductive plate on its outside.

[0070] The ends of the biased cathode conductive plate, the biased cathode conductive support cylinder, the insulating ceramic sleeve, and the split Joule heating sleeve that are away from the insulating ceramic column are flush with each other.

[0071] Optionally, the end face of the insulating ceramic fixing post with fastening threads is provided with a heat insulation pad and a protective plate in sequence.

[0072] Specifically, the protective plate is mainly to prevent damage to the electron emitter caused by laser penetration of the material.

[0073] Specifically, the heat insulation pad has the characteristics of high toughness, low coefficient of thermal expansion and low thermal conductivity, and is made of one or more of carbon fiber fabric, silicon carbide fiber fabric, graphene fiber, quartz fiber fabric, metal fiber fabric and ceramic fiber fabric, and the thickness of the heat insulation pad is 1 to 5 mm.

[0074] Specifically, the thickness of the bias cathode conductive plate is 3-8 mm, preferably 5 mm.

[0075] Specifically, the biased cathode conductive plate, the biased cathode conductive support cylinder, and the detachable conductive outer shell are electrically connected;

[0076] The biased cathode conductive plate or biased cathode conductive support cylinder is provided with biased cathode conductive terminals.

[0077] Specifically, the detachable conductive outer shell and the insulating ceramic sleeve are provided with fastening through holes at corresponding positions, and the first semi-annular sleeve is provided with a groove at a corresponding position. The through holes and grooves are used to install fastening screws, thereby achieving accurate positioning and firm connection of the first semi-annular sleeve and the second semi-annular sleeve.

[0078] Specifically, the detachable conductive housing is provided with an assembly through hole, and the biased cathode conductive support cylinder is provided with an assembly groove at a corresponding position, for tightly connecting the detachable conductive housing and the biased cathode conductive support cylinder by bolts.

[0079] It is worth noting that the tightness between the biased cathode conductive support cylinder, the insulating ceramic sleeve, and the split Joule heating sleeve is controlled by the detachable conductive outer shell.

[0080] Specifically, the fastening through hole is used to adjust the tightness between the detachable conductive shell, the insulating ceramic sleeve, and the split Joule heating sleeve; the assembly through hole is used to adjust the tightness between the bias cathode conductive support cylinder and the detachable conductive shell (actually, it also adjusts the tightness of the insulating ceramic sleeve simultaneously).

[0081] Specifically, the biased cathode conductive plate, biased cathode conductive support cylinder, detachable conductive shell and split Joule heating sleeve are made of one or more of the following materials: tungsten, molybdenum, titanium, refractory metal alloy, high-purity graphite, carbide ceramic, boride ceramic or nitride ceramic.

[0082] The insulating ceramic sleeve, insulating ceramic strip, and insulating ceramic fixing post are made of one of the following: boride, carbide, or nitride insulating ceramics.

[0083] Specifically, the protective plate is made of one or more of the following materials: tungsten, molybdenum, refractory metals and alloys, high-purity alumina ceramics, boron nitride ceramics, and zirconium oxide ceramics; the thickness of the protective plate is 1-5 mm.

[0084] Specifically, the sample receiving cavity is filled with a flexible conductive material for loading and fixing irregularly shaped test samples. For example, the flexible conductive material is one or more of high-purity graphite paper, carbon fiber adhesive, and silicon carbide fiber cloth.

[0085] Specifically, in one possible design (such as...) Figure 6 , 7 As shown, the anode section includes a plasma-excited anode plate, an anode insulating ceramic fixing ring, an anode metal support ring, and an anode ceramic support rod.

[0086] The plasma excitation anode plate, the anode insulating ceramic fixing ring, and the anode metal support ring are coaxially nested from the outside to the inside; the plasma excitation anode plate is provided with an anode conductive terminal, and the anode metal support ring is provided with a metal support ring conductive terminal; the ceramic support rod is connected to the anode insulating ceramic fixing ring at an appropriate position.

[0087] The conductive part of the anode is made of one or more of the following materials: refractory metals and alloys such as tungsten, molybdenum, and titanium; high-purity graphite; carbide ceramics; borides; or nitride high-temperature conductive ceramics.

[0088] The present invention also discloses an electron evaporation cooling material performance testing device, the device including the above-mentioned clamping device;

[0089] The equipment also includes a high vacuum test chamber, a heating module, a pressure control module, a power supply and current detection module, a temperature and surface morphology detection module, and a host computer control module.

[0090] This invention also discloses a method for testing the performance of electron evaporation cooling materials. The testing method uses the aforementioned testing equipment and specifically includes the following steps:

[0091] Step 1: Install the sample to be tested on the sample clamping device. When laser heating, assemble the heat insulation pad and protective plate. When Joule heating, only use the split Joule heating sleeve to form a current loop with the sample to be tested. Close the high vacuum test chamber.

[0092] Step 2: Adjust the cabin pressure to 1×10 using the pressure control module. -4 Below Pa, inert gas is circulated for gas replacement, and at 1×10 -4 Preheat to above 300°C under a stable pressure of Pa;

[0093] Step 3: The heating module raises the temperature, and a gradient strategy is used to control the heating rate.

[0094] When the temperature difference is greater than 1000℃, the heating rate should be ≤50℃ / min.

[0095] When the temperature difference is 200–1000℃, the heating rate should be ≤40℃ / min.

[0096] When the temperature difference is <200℃, the heating rate is ≤20℃ / min;

[0097] Step 4: The thermoelectric emission performance, cooling performance, temperature resistance performance and ablation resistance performance of the sample are jointly detected by the power supply and current detection module and the temperature and surface morphology detection module.

[0098] Example

[0099] Adopting such Figures 1-7The clamping device shown (including the cathode and anode sections) clamps the material to be tested and performs performance testing.

[0100] The key structural parameters of the (cathode section) are as follows: the thickness of the bias cathode conductive plate is 5mm, the wall thickness of the ceramic insulating sleeve is 3mm, the length of the ceramic insulating fixing post is 10cm, the thickness of the protective plate is 5mm, the thickness of the heat insulation pad is 5mm, the corresponding central angle of the detachable conductive shell is 180°, the effective engagement length of the fastening thread is 30mm, the nominal diameter is 42mm, and the pitch range is 3mm.

[0101] Step 1: Place the sample in the sample receiving cavity, attach an insulating fiber heat insulation pad behind the sample, and add a boron nitride protective plate after the heat insulation pad. Then assemble and fix the components of the entire clamping device in sequence.

[0102] Step 2: Assemble the clamping device inside the high vacuum test chamber. Connect the negative terminal of the DC regulated power supply to the conductive terminals of the first semi-annular sleeve and the second semi-annular sleeve. Connect the negative terminal of the high-precision radio frequency power supply to the conductive terminal of the bias cathode to provide the plasma atmosphere. The connecting wires are made of high-temperature resistant wires.

[0103] The anode (anode section) is installed parallel to the front of the bias cathode conductive panel, with the center opening of the anode aligned with the center of the electron emitter of the sample clamping device. The conductive terminals of the anode plate are connected to the positive terminal of the RF power supply in the power supply and current detection module to excite the inert gas and generate a plasma atmosphere. The conductive terminals of the anode metal support ring are connected to the positive terminal of the regulated DC power supply. After connection, the regulated DC power supply is turned on, and the voltage between the cathode and anode is measured using a multimeter. The actual applied bias voltage is checked and recorded. The RF power supply is turned on, and the RF voltage across the clamping device is measured and recorded using a multimeter.

[0104] Step 3: Using an external pressure and temperature control system, the heating beam passes through the center of the electron emitter of the clamping device to heat the material, with the initial heating power controlled at 5 × 10⁻⁶. 5 W / m 2 Each increment is 5×10 5 W / m 2 Maintain this temperature for 5 minutes each time to allow it to rise continuously.

[0105] The specific temperature control is as follows: when the temperature difference from the target temperature (such as the final set value) is >1000℃, the heating rate is adjusted to ≤50℃ / min; when the temperature difference decreases to within the range of 200℃ to 1000℃, the heating rate is increased to ≤40℃ / min; when the temperature difference decreases to within 200℃, the heating rate is controlled at ≤20℃ / min. Simultaneously, based on feedback data from the online infrared thermal imager and colorimetric pyrometer, the power is fine-tuned to achieve precise and rapid approach and stable control of the target temperature, ultimately ensuring that the sample temperature is stably maintained within ±5℃ of the target value. Furthermore, the excitation frequency and bias voltage of the radio frequency electric field are controlled by a power supply control device.

[0106] Step 4: After completing the sample heating and stabilizing the target temperature in Step 3, comprehensively evaluate the thermoelectric emission performance, cooling performance, temperature resistance and ablation resistance of the test material using an external information acquisition device.

[0107] The specific steps are as follows:

[0108] (1) Testing of the thermoelectric emission properties of electron-evolving materials

[0109] At the start of the experiment, the temperature and surface morphology detection module was kept running to record the sample surface temperature distribution and center point temperature in real time, and a high-speed camera was used to capture changes in surface morphology. Power was then gradually increased via the host computer (in increments of 5 × 10⁻⁶). 5 W / m 2 The experiment was initiated by maintaining a temperature rise for 5 minutes at a time. Once the sample temperature stabilized, the power control device was activated to apply a bias voltage and a radio frequency electric field. High-precision ammeters and voltmeters were used to detect the thermionic emission current and voltage signals on the sample surface, respectively. The experimental data were collected and stored for analysis of the material's thermoelectric emission efficiency and electron escape characteristics.

[0110] (2) Electron Escape Cooling Performance Testing

[0111] At the start of the experiment, the changes in sample surface temperature and morphology were recorded. Initially, the sample was heated to the target temperature using laser, and the laser heating control power was stabilized. According to the experimental requirements, the conditions were adjusted sequentially: the argon pressure (1×10⁻⁶) was changed at a flow rate of 0–500 mL / min using an electronic flow controller. -4 Pa to 1×10 2 The system adjusts the bias voltage (0-50V) and RF power (0-100W) to change the transmit current intensity (0-1A). It records the temperature change curve over time in real time, detects the cooling rate and uniformity, and analyzes the cooling performance under different conditions at a data acquisition frequency of 2Hz.

[0112] (3) Temperature resistance and ablation resistance test

[0113] At the start of the experiment, changes in sample surface temperature and morphology were recorded. The initial laser power was set to 5 × 10⁻⁶. 5 W / m 2 The power is gradually increased via the host computer (increment by 5 × 10). 5 W / m 2 Each heating cycle is maintained for 5 minutes. The experiment begins after the temperature stabilizes. Observe and record the critical temperatures and morphological characteristics at which creep, melting, boiling, or sputtering occurs on the sample surface. If any of these phenomena occur, immediately stop heating and record the corresponding heating temperature. Maintain a vacuum of 1 × 10⁻⁶. -4 Below Pa, data is stored on a host computer and used to evaluate temperature resistance limits and thermal stability. Mass loss is calculated by weighing before and after the test, and the change in the position of the heating center is measured before and after the test to evaluate ablation resistance.

[0114] During the experiment, the offset between the cathode and anode parts of the clamping device was monitored in real time. After the experiment, an inclinometer was used to check whether the cathode part was tilted. When the tilt angle was ≤0.5°, it indicated that the material had not shifted. Furthermore, the deviation between the center of the laser heating point and the material's central axis was compared. When the deviation was ≤0.01mm, it indicated that the clamping device had not shifted or slipped. In the actual test, no tilting or displacement of the test material occurred.

[0115] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A super-high temperature resistant clamping device, characterized in that, The clamping device comprises a cathode part and an anode part; The cathode part comprises a bias cathode conductive plate (1), a bias cathode conductive support cylinder (2), a detachable conductive shell (3), an insulating ceramic sleeve (11), a split type joule heating sleeve, an insulating ceramic strip (13), and an insulating ceramic fixed column (6). The split type joule heating sleeve comprises a first half ring sleeve (14) and a second half ring sleeve (15); an insulating ceramic strip (13) is arranged between the abutting edges of the first half ring sleeve (14) and the second half ring sleeve (15); a fastening thread (17) is arranged at the corresponding positions of the inner walls of the first half ring sleeve (14) and the second half ring sleeve (15) and one end of the insulating ceramic fixed column (6), for fixing the insulating ceramic fixed column (6) in the inner cavity of the split type joule heating sleeve in a screw-in manner; the end face of the end of the insulating ceramic fixed column (6) provided with the fastening thread (17) and the inner wall of the split type joule heating sleeve jointly form a sample containing cavity (16); The end face of the insulating ceramic fixed column (6) provided with the fastening thread (17) is sequentially provided with a heat insulation pad (18) and a protective plate (19); The split type joule heating sleeve is externally provided with an insulating ceramic sleeve (11); the insulating ceramic sleeve (11) is externally provided with the bias cathode conductive support cylinder (2) and the detachable conductive shell (3), which jointly form a complete cylindrical structure and are matched with the shape of the outer wall of the insulating ceramic sleeve (11); The bias cathode conductive plate (1), the bias cathode conductive support cylinder (2), and the detachable conductive shell (3) are electrically connected; a bias cathode conductive terminal (8) is arranged on the bias cathode conductive plate (1) or the bias cathode conductive support cylinder (2); The bias cathode conductive plate (1) is arranged outside the bias cathode conductive support cylinder (2) in a ring shape; the bias cathode conductive plate (1), the bias cathode conductive support cylinder (2), the insulating ceramic sleeve (11), and the split type joule heating sleeve are coaxially nested and installed, and the end faces of the bias cathode conductive plate (1) and the bias cathode conductive support cylinder (2) away from the insulating ceramic column are flush with each other.

2. The clamping device of claim 1, wherein The bias cathode conductive plate (1) is 3-8 mm thick.

3. The clamping device of claim 1, wherein Corresponding positions of the detachable conductive shell (3) and the insulating ceramic sleeve (11) are provided with fastening through holes, and corresponding positions of the first half ring sleeve (14) are provided with fastening grooves, which are used for arranging fastening screws to realize accurate positioning and firm connection of the first half ring sleeve (14) and the second half ring sleeve (15).

4. The clamping device of claim 1, wherein The detachable conductive shell (3) is provided with an assembly through hole, and the corresponding position of the bias cathode conductive support cylinder (2) is provided with an assembly groove, which are used for tightly connecting the detachable conductive shell (3) and the bias cathode conductive support cylinder (2) through bolts.

5. The clamping device of claim 1, wherein The bias cathode conductive plate (1), the bias cathode conductive support cylinder (2), the detachable conductive shell (3) and the split type Joule heating sleeve are made of one or more of tungsten, molybdenum, titanium, refractory metal alloy, high-purity graphite, carbide ceramic, boride ceramic or nitride ceramic; The insulation ceramic sleeve (11), the insulation ceramic strip (13) and the insulation ceramic fixing column (6) are made of one or more of boride, carbide or nitride insulation ceramic.

6. The clamping device of claim 1, wherein The protective plate (19) is made of one or more of tungsten, molybdenum, refractory metal and its alloy material, high-purity alumina ceramic, boron nitride ceramic and zirconia ceramic; the thickness of the protective plate (19) is 1-5 mm.

7. The clamping device of claim 1, wherein The sample containing cavity (16) is filled with a flexible conductive material for loading and fixing of the sample with a special-shaped structure.

8. An electronically- cooled material performance testing apparatus, characterized by, The device comprises the clamping device of any one of claims 1-7; The device further comprises a high-vacuum test chamber, a heating module, a pressure control module, a power supply and current detection module, a temperature and surface topography detection module and an upper computer control module.

9. A method of testing the performance of an electron emission cooling material, characterized by, The test method uses the test device of claim 8 and specifically comprises the following steps: Step 1: installing the sample to be tested in the sample clamping device; Assembling the heat insulation pad (18) and the protective plate (19) when laser heating; When Joule heating, only the split type Joule heating sleeve is used to form a current loop with the sample to be tested; Step 3: heating by the heating module, using a gradient strategy to control the heating rate: Step 2: Adjust the cabin pressure to 1 x 10 -4 Pa below by the pressure control module, and preheat to 300 ℃ or above under the stable pressure of 1 x 10 -4 Pa with the circulation of inert gas for gas replacement. When the temperature difference is greater than 1000℃, the heating rate is less than or equal to 50℃ / min; When the temperature difference is 200-1000℃, the heating rate is less than or equal to 40℃ / min; When the temperature difference is less than 200℃, the heating rate is less than or equal to 20℃ / min; Step 4: jointly detecting the thermoelectric emission performance, cooling performance, temperature resistance and ablation resistance of the sample by the power supply and current detection module and the temperature and surface topography detection module. ​

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