Ultrahigh-temperature-resistant clamping device and application thereof

Abstract

The invention relates to an ultra-high-temperature-resistant clamping device and application thereof, belongs to the technical field of joint inspection of performance of electron escape cooling materials, and solves the problem that the existing conventional clamping device has the defects of material deviation, device toppling, incapability of providing a bias electric field and the like under an ultra-high-temperature condition and is difficult to meet test requirements. The invention provides an ultrahigh-temperature-resistant clamping device. The clamping device comprises a cathode part and an anode part, wherein the cathode part comprises a bias cathode conductive plate, a bias cathode conductive supporting cylinder, a detachable conductive shell, an insulating ceramic sleeve, a split joule heating sleeve, an insulating ceramic strip and an insulating ceramic fixing column. The clamping device supports multiple heating modes, the material potential can be flexibly changed, and the clamping stability can be kept under the extreme conditions of ultra-high temperature and application of a bias electric field; by combining a matched high-pressure vacuum experiment module and a test method, various properties of the electron escape material in a real service state can be tested.

Description

Technical Field

[0001] The present invention relates to the technical field of electron escape cooling material performance joint inspection, in particular to an ultra-high temperature resistant clamping device and application thereof. Background Art

[0002] As a new type of thermal protection material with broad application prospects, accurate, rapid, and simultaneous detection and analysis of its thermoelectric emission, electron escape cooling, and temperature resistance are crucial prerequisites for the development of high-performance electron escape cooling materials. Thermoelectric emission performance is typically analyzed based on the material's thermoelectric emission curve. Electron escape cooling performance is currently primarily determined by indirectly determining the material's electron escape capacity through testing its work function, which in turn allows analysis of the material's electron escape 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 central ablation recession rate.

[0003] However, there is currently no mature detection device for simultaneous analysis of electron escape materials in application environments above 2000°C. Existing detection methods for basic electron escape cooling performance, heat resistance, and thermoelectric performance of electron escape cooling materials are mostly based on relatively independent analytical tests. Such electron escape material detection methods are often unable to perform online detection based on the actual service status of the material, and are unable to obtain in real time the true performance of the material under the synergistic influence of the multimodal performance of the electron escape material. Moreover, in a high vacuum and ultra-high temperature environment, the clamping and fixing devices of the electron escape material often cause problems such as slippage and offset under the influence of gravity due to differences in thermal expansion coefficients. This is an important factor affecting the authenticity of material performance detection. Summary of the Invention

[0004] In view of the above analysis, an embodiment of the present invention aims to provide an ultra-high temperature resistant clamping device and its application, so as to solve at least one of the defects of existing conventional clamping devices under ultra-high temperature conditions, such as material deviation, device tipping, and inability to provide a bias electric field.

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

[0006] The cathode part includes a biased cathode conductive plate 1, a biased cathode conductive support tube 2, a detachable conductive 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 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 butt joint edges of the first semi-annular sleeve 14 and the second semi-annular sleeve 15, and there are two insulating ceramic strips 13 in total;

[0008] The corresponding positions of 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 column 6 are provided with fastening threads 17 for fixing the insulating ceramic fixing column 6 in the inner cavity of the split Joule heating sleeve by screwing;

[0009] The end surface of the insulating ceramic fixing column 6 provided with a fastening thread 17 and the inner wall of the split Joule heating sleeve together form a sample receiving chamber 16 to be tested;

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

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

[0012] The outside of the bias cathode conductive support cylinder 2 is provided with a ring-shaped bias cathode conductive plate 1;

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

[0014] Optionally, the end surface of the insulating ceramic fixing column 6 provided with the fastening thread 17 is sequentially provided with a thermal insulation pad 18 and a protective plate 19.

[0015] Specifically, the bias cathode conductive plate 1 has a thickness of 3 to 8 mm.

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

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

[0018] Specifically, the detachable conductive shell 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, which is used to tightly connect the detachable conductive shell 3 and the biased cathode conductive support cylinder 2 through bolts.

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

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

[0021] Specifically, the material of the protective plate 19 is one or more of tungsten, molybdenum, refractory metals and alloy materials, high-purity alumina ceramics, boron nitride ceramics and zirconia ceramics; the thickness of the protective plate 19 is 1 to 5 mm.

[0022] Specifically, the sample holding cavity 16 is filled with a flexible conductive material for loading and fixing samples with special-shaped structures to be tested.

[0023] The present invention also discloses an electron escape cooling material performance testing device, the device comprising 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] The present invention also discloses a method for testing the performance of an electron escape cooling material. The method uses the above-mentioned testing equipment and specifically includes the following steps:

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

[0027] Step 2: The cabin pressure is adjusted to below 1×10-4Pa by the pressure control module, an inert gas is circulated to perform gas replacement, and the cabin is preheated to above 300°C at a stable pressure of 1×10-4Pa;

[0028] Step 3: Raise the temperature through the heating module and use a gradient strategy to control the heating rate:

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

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

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

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

[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 realizes stable clamping in an ultra-high temperature vacuum environment through structural design and material selection. The applicable temperature is not lower than 2000°C, and it supports Joule heating, laser heating and other modes, and can provide a bias electric field.

[0035] During the performance test of electron escape materials, it is necessary to test the thermoelectric emission performance, electron escape cooling performance and heat resistance of the material. The performance test of electron escape materials usually adopts laser heating, Joule heating and other methods. Among them, laser heating in particular requires the material position to remain absolutely consistent. Once the position of the material changes, it is possible to change the heating position or cause the optical path to emit offsets, resulting in safety hazards. Therefore, the material to be tested needs to be able to not produce relative displacement at high temperatures. During the high-temperature experiment, the clamping device provided by the present invention is internally provided with a multi-layer fixing device, which can effectively prevent the relative displacement of components caused by the difference in thermal expansion coefficients between different materials. For example, after the biased cathode conductive support cylinder, the detachable conductive shell, the insulating ceramic sleeve, the split Joule heating sleeve, the insulating ceramic strip and the insulating ceramic fixing column are assembled, they form a solid whole under the locking of the assembly bolts, the fastening bolts and the fastening threads. Even if there are certain differences in the thermal expansion coefficients of the components, no relative displacement will occur at high temperatures, thereby avoiding displacement of the clamped sample.

[0036] In addition, when the material is Joule heated, the clamping device needs to have independent positive and negative electrodes to perform Joule heating on the electron escaping material. In addition, when the performance of the electron escaping material is tested, this heating process usually requires applying a bias voltage between the outer wall surface of the material side and the anode. Therefore, the positive and negative electrodes in the clamping device that apply Joule heating to the electron escaping material need to be independent of the bias voltage field of the material wall surface and do not affect each other. Therefore, the present invention sets an insulating ceramic layer (mainly an insulating ceramic sleeve) outside the positive and negative electrodes used for Joule heating of the electron escaping material to isolate the outer layer of the electron escaping material from the bias voltage applied to the shell.

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

[0038] 2. The holding cavity of the clamping device provided by the present invention can accommodate test materials of various shapes, regardless of material size, and can be used for targeted testing of irregularly shaped materials. It is worth noting that when testing irregularly shaped materials, the holding cavity needs to be filled with a flexible conductive material to prevent the material from slipping.

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

[0040] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following description, and some advantages will become apparent from the description or be learned through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like parts throughout the drawings.

[0042] Figure 1 It is a schematic diagram of the overall structure of the cathode part of a clamping device that can withstand ultra-high temperatures;

[0043] Figure 2 It is a top view schematic diagram of the overall structure of the cathode part of the ultra-high temperature resistant clamping device;

[0044] Figure 3 It is a side view of the local structure and assembly relationship of the insulating ceramic sleeve of the cathode part of the ultra-high temperature resistant clamping device;

[0045] Figure 4 It is a side view of the partial structure and assembly relationship of the cathode-type Joule heating sleeve of the ultra-high temperature resistant clamping device;

[0046] Figure 5 It is a schematic cross-sectional view of the overall structure of the cathode portion of a clamping device that is resistant to ultra-high temperatures;

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

[0048] Figure 7 A cross-sectional view of a possible anode structure.

[0049] Reference numerals:

[0050] 1. Biased cathode conductive plate; 2. Biased cathode conductive support cylinder; 3. Removable conductive housing; 4. First fastening through-hole; 5. First semi-annular sleeve conductive terminal; 6. Insulating ceramic fixing column; 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 holding chamber; 17. Fastening thread; 18. Thermal insulation pad; 19. Protective plate.

[0051] 20. Plasma excitation anode plate; 21. Anode plate conductive terminal; 22. Anode insulating ceramic fixing ring; 23. Anode metal support ring; 24. Anode metal support ring conductive terminal; 25. Anode ceramic support column. DETAILED DESCRIPTION

[0052] The preferred embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, and are not used to limit the scope of the present invention.

[0053] The clamping device provided by the present invention can withstand laser heating and ultra-high temperature heating environments, and can realize functions such as Joule heating and material wall bias voltage control. The internal structure can avoid problems such as slippage and dislocation caused by differences in thermal expansion coefficients of different materials in the internal structure of the clamping device. It is suitable for extreme testing environments above 2000°C, and is particularly suitable for comprehensive performance testing of electron escape materials in ultra-high temperature vacuum environments.

[0054] Currently, there are no public reports on the performance testing of electron escape materials in extreme environments. Through theoretical research and experimental exploration, the R&D team has identified the following difficulties or technical problems that need to be solved urgently and proposed possible solutions:

[0055] (1) During the performance test of electron escaping materials, it is necessary to test the thermoelectric emission performance, electron escape cooling performance, and heat resistance of the material. The performance test of electron escaping materials usually adopts laser heating, Joule heating, etc. Among them, laser heating, in particular, requires the position of the material to remain absolutely consistent. Once the position of the material changes, it is possible to change the heating position or cause the optical path to emit offsets, resulting in safety hazards. Therefore, the material to be tested needs to be able to not produce relative displacement at high temperatures. In addition, when the material uses Joule heating, the clamping device needs to have independent positive and negative electrodes to Joule heat the electron escaping material. In addition, when the performance of the electron escaping material is tested, this heating process usually requires applying a bias voltage between the outer wall surface of the material side and the anode. Therefore, the positive and negative electrodes in the clamping device that apply Joule heating to the electron escaping material need to be independent of the bias voltage field of the material wall surface and do not affect each other. Therefore, the positive and negative electrodes used for Joule heating of the electron escaping material in the present invention need an insulating ceramic layer on the outside to isolate the outer shell from the bias voltage applied to the outer layer of the electron escaping material.

[0056] (2) During high-temperature experiments, in order to prevent the differences in thermal expansion coefficients between different materials from causing relative positioning of components, multiple layers of fixing devices need to be set up inside the device.

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

[0058] The cathode part includes a biased cathode conductive plate, a biased cathode conductive support tube, a detachable conductive shell, an insulating ceramic sleeve, a split Joule heating sleeve, an insulating ceramic strip, an insulating ceramic fixing column, a protective plate, and a thermal insulation pad;

[0059] The split Joule heating sleeve comprises a first semi-annular sleeve and a second semi-annular sleeve; an insulating ceramic strip is provided between the butting edges of the first semi-annular sleeve and the second semi-annular sleeve, and there are two insulating ceramic strips in total;

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

[0061] The corresponding positions of the inner walls of the first semi-annular sleeve and the second semi-annular sleeve and one end of the insulating ceramic fixing column are provided with fastening threads for fixing the insulating ceramic fixing column in the inner cavity of the split Joule heating sleeve by screwing;

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

[0063] The end surface of the insulating ceramic fixing column provided with a fastening thread and the inner wall of the split Joule heating sleeve together form a sample receiving chamber to be tested;

[0064] Conductive terminals for heating are provided on the outer walls of the first semi-annular sleeve and the second semi-annular sleeve;

[0065] The split Joule heating sleeve is provided with an insulating ceramic sleeve on the outside;

[0066] The insulating ceramic sleeve has a wall thickness of 1 to 5 mm, preferably 3 mm, to isolate the positive and negative electrodes of Joule heating from the biased 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 shell on the outside, and the biased cathode conductive support cylinder and the detachable conductive shell together form a complete cylindrical structure and match the outer wall shape of the insulating ceramic sleeve;

[0068] The detachable conductive shell is a semi-enclosed structure, connected to the biased cathode conductive support cylinder by bolts and built-in nuts, and the central angle corresponding to the semi-enclosed structure ranges from 60 to 270 degrees, preferably 180 degrees;

[0069] The bias cathode conductive support cylinder is provided with an annular bias cathode conductive plate on the outside;

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

[0071] Optionally, the end surface of the insulating ceramic fixing column provided with a fastening thread is sequentially provided with a thermal insulation pad and a protective plate.

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

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

[0074] Specifically, the bias cathode conductive plate has a thickness of 3 to 8 mm, preferably 5 mm.

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

[0076] The bias cathode conductive plate or the bias cathode conductive support cylinder is provided with a bias cathode conductive terminal.

[0077] Specifically, fastening through holes are provided at corresponding positions of the detachable conductive shell and the insulating ceramic sleeve, and grooves are provided at corresponding positions of the first semi-annular sleeve. The through holes and grooves are used to set fastening screws to achieve accurate positioning and firm connection of the first semi-annular sleeve and the second semi-annular sleeve.

[0078] Specifically, the detachable conductive shell is provided with an assembly through hole, and the biased cathode conductive support cylinder is provided with an assembly groove at a corresponding position, which is used to tightly connect the detachable conductive shell and the biased cathode conductive support cylinder through bolts.

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

[0080] Specifically, the fastening through hole is used to adjust the fastening degree between the detachable conductive shell, the insulating ceramic sleeve and the split Joule heating sleeve; the assembly through hole is used to adjust the fastening degree between the biased cathode conductive support tube and the detachable conductive shell (in fact, the fastening degree of the insulating ceramic sleeve is also adjusted synchronously).

[0081] Specifically, the biased cathode conductive plate, the biased cathode conductive support cylinder, the detachable conductive shell and the split 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;

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

[0083] Specifically, the material of the protective plate is one or more of tungsten, molybdenum, refractory metals and alloy materials, high-purity alumina ceramics, boron nitride ceramics and zirconia ceramics; the thickness of the protective plate is 1 to 5 mm.

[0084] Specifically, the sample holding cavity is filled with a flexible conductive material for loading and fixing the sample with a special structure to be tested. Exemplarily, the flexible conductive material is one or more of high-purity graphite paper, carbon fiber adhesive, and silicon carbide fiber cloth.

[0085] Specifically, in a possible design (such as Figure 6 、 7 As shown), the anode part includes a plasma excitation 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 and connected 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 appropriate position of the anode insulating ceramic fixing ring.

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

[0088] The present invention also discloses an electron escape cooling material performance testing device, the device comprising 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] The present invention also discloses a method for testing the performance of an electron escape cooling material. The method uses the above-mentioned testing equipment and specifically includes the following steps:

[0091] Step 1: Install the sample to be tested on the sample holding device. Install a thermal insulation pad and a protective plate during laser heating. During Joule heating, only use the split Joule heating sleeve to form a current loop with the sample to be tested, and close the high vacuum test chamber.

[0092] Step 2: Use the pressure control module to adjust the cabin pressure to 1×10 -4 Pa, the inert gas was filled in the cycle for gas replacement, and the -4 Preheat to above 300℃ under a stable pressure of Pa;

[0093] Step 3: Raise the temperature through the heating module and use a gradient strategy to control the heating rate:

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

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

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

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

[0098] Example

[0099] Use Figures 1 to 7The clamping device shown (including cathode and anode parts) is used to clamp the material to be tested and perform performance testing:

[0100] (Cathode part) The key structural parameters are as follows: the thickness of the biased cathode conductive plate is 5mm, the wall thickness of the ceramic insulating sleeve is 3mm, the length of the ceramic insulating fixing column is 10cm, the thickness of the protective plate is 5mm, the thickness of the thermal insulation pad is 5mm, the corresponding central angle of the detachable conductive shell is 180°, the effective thread 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 holding chamber, attach an insulating fiber thermal pad behind the sample, and add a boron nitride protective plate behind the thermal pad. Then assemble and fix the various components of the entire clamping device in sequence.

[0102] Step 2: Assemble the entire clamping device in a high vacuum test chamber, connect the negative electrode of a DC regulated power supply to the conductive terminals of the first and second semi-annular sleeves, and connect the negative electrode of a high-precision RF power supply to the bias cathode conductive terminal to provide a plasma atmosphere. Use high-temperature resistant wires for the connected wires.

[0103] Install the anode (anode portion) parallel to the biased cathode conductive panel, aligning the anode's central opening with the center of the electron emitter in the sample holder. Connect the anode plate's conductive terminal to the positive terminal of the RF power supply in the power and current detection module to excite the inert gas and generate a plasma atmosphere. Connect the anode's metal support ring's conductive terminal to the positive terminal of a regulated DC power supply. After connection, turn on the regulated DC power supply and use a multimeter to measure the voltage between the cathode and anode, checking and recording the actual applied bias voltage. Turn on the RF power supply and use a multimeter to measure and record the RF voltage across the holder.

[0104] Step 3: Through the 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. The initial heating power is controlled at 5×10 5 W / m 2 , each increment is 5×10 5 W / m 2 , maintain for 5 minutes each time to allow the temperature to continue to rise.

[0105] The specific temperature increase control is as follows: when the temperature difference from the target temperature (e.g., the final set point) is greater than 1000°C, the heating rate is adjusted to ≤50°C / min; when the temperature difference decreases to within the range of 200°C to 1000°C, the heating rate is increased to ≤40°C / min; when the temperature difference decreases to within 200°C, the heating rate is controlled to ≤20°C / min. Simultaneously, combined with feedback data from the online infrared thermal imager and colorimetric pyrometer, the power is fine-tuned to achieve precise, rapid approach to the target temperature and stable control, ultimately ensuring that the sample temperature is maintained within ±5°C of the target value. In addition, the RF electric field excitation frequency and bias voltage are controlled by the power control device.

[0106] Step 4: After completing the sample heating in step 3 and stabilizing the target temperature, use an external information collection device to comprehensively evaluate the thermoelectric emission performance, cooling performance, temperature resistance, and ablation resistance of the material to be tested.

[0107] The specific operations are as follows:

[0108] (1) Detection of thermoelectric emission performance of electron escape materials

[0109] At the beginning of the test, the temperature and surface morphology detection module was kept running, the surface temperature distribution and the center point temperature of the sample were recorded in real time, and the surface morphology changes were captured by a high-speed camera. The power was gradually increased by the host computer (increment 5×10 5 W / m 2 The test begins with a continuous temperature rise (e.g., 5 minutes each time). Once the sample temperature stabilizes, the power control device is activated to apply a bias voltage and RF electric field. A high-precision ammeter and voltmeter are used to measure the thermal electron emission current and voltage signals on the sample surface, respectively. The experimental data is collected and stored for analysis of the material's thermal emission efficiency and electron escape characteristics.

[0110] (2) Electron escape cooling performance test

[0111] At the beginning of the experiment, the surface temperature and morphology of the sample were recorded. In the initial state, the laser heated the sample to the target temperature and the laser heating control power was stabilized. According to the experimental requirements, the conditions were adjusted in sequence: the argon pressure (1×10 -4 Pa to 1×10 2 Pa), adjust the bias voltage (0-50V), and adjust the RF power (0-100W) to change the emission current intensity (0-1A). Real-time temperature change curves were recorded over time to detect cooling rate and uniformity. Data acquisition frequency was 2Hz, and cooling performance under different conditions was analyzed.

[0112] (3) Heat resistance and ablation resistance testing

[0113] At the beginning of the test, the surface temperature and morphology of the sample were recorded. The initial laser power was set to 5×10 5 W / m 2 , gradually increase the power through the host computer (increment 5×10 5 W / m 2 , each time for 5 minutes), and start the test after the temperature stabilizes. Observe and record the critical temperature and morphological characteristics of the sample surface when creeping, melting, boiling or sputtering occurs. If the above phenomenon occurs, stop heating immediately and record the corresponding heating temperature. Maintain the vacuum degree at 1×10 -4 Below Pa, the data is stored by the host computer and used to evaluate the temperature resistance limit and thermal stability. The mass loss is calculated by weighing before and after the test, and the change in the heating center position before and after is measured to evaluate the anti-ablation performance.

[0114] During the test, the cathode and anode sections of the clamping device were monitored in real time for any deviation. After the test, an inclinometer was used to check for tilting of the cathode. A tilt angle of 0.5° or less indicated no material deviation. Furthermore, the center of the laser heating point was compared with the material's central axis for deviation. A deviation of 0.01mm or less indicated no deviation or slippage of the clamping device. During the actual test, no tilting or displacement of the material was observed.

[0115] The above description is only a preferred specific 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 thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. A clamping device resistant to ultra-high temperatures, characterized in that: The clamping device includes a cathode portion and an anode portion; The cathode portion includes a biased cathode conductive plate (1), a biased cathode conductive support tube (2), a detachable conductive shell (3), an insulating ceramic sleeve (11), a split Joule heating sleeve, an insulating ceramic strip (13), and an insulating ceramic fixing column (6); The split Joule heating sleeve comprises a first semi-annular sleeve (14) and a second semi-annular sleeve (15); an insulating ceramic strip (13) is provided between the butting edges of the first semi-annular sleeve (14) and the second semi-annular sleeve (15); fastening threads (17) are provided at corresponding positions of the inner walls of the first semi-annular sleeve (14) and the second semi-annular sleeve (15) and at one end of the insulating ceramic fixing column (6), for fixing the insulating ceramic fixing column (6) in the inner cavity of the split Joule heating sleeve by screwing; the end surface of the insulating ceramic fixing column (6) at one end of which the fastening threads (17) are provided and the inner wall of the split Joule heating sleeve together form a sample receiving cavity (16) to be tested; An insulating ceramic sleeve (11) is provided on the outside of the split Joule heating sleeve; a biased cathode conductive support cylinder (2) and a detachable conductive shell (3) are provided on the outside of the insulating ceramic sleeve (11); the biased cathode conductive support cylinder (2) and the detachable conductive shell (3) together form a complete cylindrical structure and match the shape of the outer wall of the insulating ceramic sleeve (11); An annular biased cathode conductive plate (1) is provided on the outside of the biased cathode conductive support cylinder (2); the biased cathode conductive plate (1), the biased 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 surfaces away from the insulating ceramic column are flush with each other.

2. The clamping device according to claim 1, characterized in that The end surface of the insulating ceramic fixing column (6) provided with a fastening thread (17) is sequentially provided with a heat insulation pad (18) and a protective plate (19).

3. The clamping device according to claim 1, characterized in that The bias cathode conductive plate (1) has a thickness of 3 to 8 mm, and the bias cathode conductive plate (1), the bias cathode conductive support tube (2) and the detachable conductive shell (3) are electrically connected; the bias cathode conductive plate (1) or the bias cathode conductive support tube (2) is provided with a bias cathode conductive terminal (8).

4. The clamping device according to claim 1, characterized in that Through holes for fastening are provided at corresponding positions of the detachable conductive shell (3) and the insulating ceramic sleeve (11), and grooves for fastening are provided at corresponding positions of the first semi-annular sleeve (14). The through holes and the grooves are used to set fastening screws to achieve accurate positioning and firm connection of the first semi-annular sleeve (14) and the second semi-annular sleeve (15).

5. The clamping device according to claim 1, characterized in that The detachable conductive shell (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 shell (3) and the biased cathode conductive support cylinder (2) via bolts.

6. The clamping device according to claim 1, characterized in that The biased cathode conductive plate (1), the biased cathode conductive support cylinder (2), the detachable conductive shell (3) and the split Joule heating sleeve are made of one or more of tungsten, molybdenum, titanium, refractory metal alloy, high-purity graphite, carbide ceramics, boride ceramics or nitride ceramics; The insulating ceramic sleeve (11), the insulating ceramic strip (13) and the insulating ceramic fixing column (6) are made of one or more of boride, carbide or nitride insulating ceramics.

7. The clamping device according to claim 2, characterized in that: The material of the protective plate (19) is one or more of tungsten, molybdenum, refractory metals and alloy materials thereof, high-purity alumina ceramics, boron nitride ceramics and zirconium oxide ceramics; the thickness of the protective plate (19) is 1 to 5 mm.

8. The clamping device according to claim 1, characterized in that: The sample holding cavity (16) is filled with a flexible conductive material and is used for loading and fixing samples with special-shaped structures to be tested.

9. An electron escape cooling material performance testing device, characterized in that: The apparatus comprises the clamping device according to any one of claims 1 to 8; 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.

10. A method for testing the performance of an electron escape cooling material, characterized in that: The testing method uses the testing device according to claim 9, and specifically comprises the following steps: Step 1: Install the sample to be tested on the sample holding device; When laser heating is performed, a heat insulating pad (18) and a protective plate (19) are assembled; During Joule heating, only the split Joule heating sleeve is used to form a current loop with the sample to be tested; Close the high vacuum test chamber; Step 2: The cabin pressure is adjusted to below 1×10-4Pa by the pressure control module, an inert gas is circulated to perform gas replacement, and the cabin is preheated to above 300°C at a stable pressure of 1×10-4Pa; Step 3: Raise the temperature through the heating module and use a gradient strategy to control the heating rate: When the temperature difference is greater than 1000℃, the heating rate is ≤50℃ / min. When the temperature difference is 200~1000℃, the heating rate is ≤40℃ / min. When the temperature difference is less than 200℃, the heating rate is ≤20℃ / min; Step 4: The power supply and current detection module and the temperature and surface morphology detection module are used to jointly detect the thermoelectric emission performance, cooling performance, temperature resistance and ablation resistance of the sample.

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