A device for measuring hydrogen isotope permeability and a method for using the same

Abstract

The present invention discloses a device for measuring hydrogen isotope permeation and a method for using the device. The device comprises a mass spectrometer, a standard leak, a vacuum pump assembly, a first vacuum valve, a second vacuum valve, a plasma discharge chamber, a bias power supply, a thermocouple, a temperature recorder, a plasma source, and a hydrogen cylinder. The plasma discharge chamber includes an isolator, a permeation line, a heater, and a sample stage for sealing and securing the metal sample. The technical solution of the present invention enables simple and convenient measurement of hydrogen isotope permeation through a metal sample under plasma irradiation conditions, unconstrained by the experimental conditions and operating time of large scientific facilities such as tokamaks.

Description

Technical Field

[0001] The present invention relates to the field of fusion device measurement technology, and in particular to a device for measuring hydrogen isotope penetration and a method for using the device. Background Art

[0002] Deuterium-tritium reactions are the most promising form of controlled nuclear fusion, so fusion reactors typically use hydrogen isotopes deuterium and tritium as fuel. Magnetic confinement fusion reactors achieve fusion reactions by confining high-temperature plasmas of several thousand eV in strong magnetic fields. The plasma reaching the reactor boundary still has energies ranging from a few to several hundred eV. The operating temperature of the plasma-facing materials within the reactor ranges from several hundred degrees Celsius to thousands of degrees Celsius. At high temperatures, hydrogen isotopes can easily penetrate materials and enter the cooling circuit. This is especially true for expensive and radioactive tritium, which can irradiate materials in a plasma state at the reactor boundary and penetrate into the coolant, impacting the reactor's economics and safety. Therefore, measuring hydrogen isotope penetration is crucial.

[0003] Currently, due to the limitations of experimental conditions and operating time of large scientific facilities such as tokamaks, it is not possible to conveniently conduct experimental evaluation of the hydrogen isotope permeation during steady-state operation of future fusion reactors. In addition, the measurement of hydrogen isotope permeation in the laboratory is usually carried out under conditions of hydrogen exposure. Under plasma irradiation conditions, the presence of plasma current and the conductivity of the sample make it difficult to measure the permeation of hydrogen isotopes. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a device for measuring hydrogen isotope permeation and a method for using the same, which can simply and conveniently measure the permeation of hydrogen isotopes through a metal sample under plasma irradiation conditions, without being restricted by the experimental conditions and operating time of large scientific facilities such as tokamaks.

[0005] To achieve the above-mentioned objectives, an embodiment of the present invention provides a device for measuring hydrogen isotope permeation, which is used to measure the permeation of hydrogen isotopes through a metal sample under plasma irradiation conditions. The device comprises: a mass spectrometer, a standard leak, a vacuum pump assembly, a first vacuum valve, a second vacuum valve, a plasma discharge chamber, a bias power supply, a thermocouple, a temperature recorder, a plasma source, and a hydrogen cylinder; the plasma discharge chamber comprises an isolator, a permeation line, a heater, and a sample stage, and the sample stage is used to seal and fix the metal sample;

[0006] One end of the isolator is connected to the sample stage through the permeation line; the heater is disposed in the permeation line and maintains a preset distance from the sample stage; the outlet of the plasma source and the outlet of the hydrogen bottle are both connected to the plasma discharge chamber; the bias power supply is connected between the outer shell of the plasma discharge chamber and the sample stage; the thermocouple is connected between the sample stage and the temperature recorder;

[0007] The other end of the isolator is connected to the mass spectrometer through a first pipeline, connected to the standard leak hole through a second pipeline, and connected to the vacuum pump group through a third pipeline, and the first pipeline, the second pipeline, and the third pipeline at one end close to the isolator are merged into one pipeline and then connected to the other end of the isolator; the first vacuum valve is arranged at one end of the second pipeline close to the standard leak hole; the second vacuum valve is arranged at one end of the merged pipeline close to the isolator.

[0008] Furthermore, the positive electrode of the bias power supply is connected to the outer shell of the plasma discharge chamber, the negative electrode of the bias power supply is connected to the sample stage, and the outer shell of the plasma discharge chamber is grounded.

[0009] Furthermore, the sample stage includes a flange sealing structure, and the flange sealing structure includes a knife-edge flange, a gasket, a cover plate and fasteners.

[0010] Furthermore, the vacuum pump group is a molecular pump group, and the isolator is a ceramic isolator.

[0011] Furthermore, the plasma source is a microwave plasma source, a radio frequency plasma source or a hot cathode plasma source.

[0012] To achieve the above objectives, an embodiment of the present invention further provides a method for using a device for measuring hydrogen isotope permeation, which is applied to any of the above-mentioned devices for measuring hydrogen isotope permeation, comprising:

[0013] The metal sample is sealed and fixed on the sample stage;

[0014] Close the first vacuum valve, open the second vacuum valve, and use the vacuum pump group to vacuum the permeate pipeline;

[0015] When the vacuum level in the permeation line reaches a preset vacuum level threshold, the mass spectrometer is turned on to start a hydrogen isotope permeation experiment. The permeation experiment includes: heating the metal sample with a heater, applying a bias voltage to the metal sample with a bias power supply, and turning on a hydrogen cylinder and a plasma source to bombard the metal sample with the generated plasma.

[0016] After the permeation experiment is completed, the first vacuum valve is opened, the second vacuum valve is closed, the standard leak is opened, and the steady-state current value of the mass spectrometer under the current sample temperature and the current ion incident energy is recorded;

[0017] The steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions is obtained according to the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer and the steady-state current value.

[0018] Furthermore, the method further comprises:

[0019] Recording the permeation change state of hydrogen isotopes in real time during the permeation experiment;

[0020] judging whether a stable permeation state has been reached according to the permeation change state;

[0021] When it is determined that a stable permeation state is reached, the permeation experiment is terminated.

[0022] Furthermore, obtaining the steady-state permeation of hydrogen isotopes through the metal sample under plasma irradiation conditions based on the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer, and the steady-state current value specifically includes:

[0023] According to the formula Calculate the steady-state permeation of hydrogen isotopes through the metal sample under plasma irradiation conditions; wherein, J ∞ is the steady-state permeability, S calib is the standard leakage rate of the standard leak hole, A is the effective penetration area of ​​the metal sample, I ∞ is the steady-state current value, I calib is the steady-state calibration current value of the mass spectrometer.

[0024] Furthermore, the method further comprises:

[0025] The heater is used to adjust the sample temperature of the metal sample to measure the steady-state permeation of hydrogen isotopes at different sample temperatures.

[0026] Furthermore, the method further comprises:

[0027] The bias power supply is used to adjust the ion incident energy of the plasma to measure the steady-state permeation of hydrogen isotopes at different ion incident energies.

[0028] Compared with the prior art, the embodiment of the present invention provides a device for measuring hydrogen isotope permeation and a method for using the same. The device includes a mass spectrometer, a standard leak, a vacuum pump group, a first vacuum valve, a second vacuum valve, a plasma discharge chamber, a bias power supply, a thermocouple, a temperature recorder, a plasma source, and a hydrogen cylinder. The plasma discharge chamber includes an isolator, a permeation pipeline, a heater, and a sample stage. The method for using the device includes: sealing a metal sample and fixing it on the sample stage; closing the first vacuum valve, opening the second vacuum valve, and evacuating the permeation pipeline using the vacuum pump group; when the vacuum degree in the permeation pipeline reaches a predetermined value, the permeation pipeline is evacuated. When a vacuum threshold is set, the mass spectrometer is turned on and a hydrogen isotope permeation experiment is started, that is, the metal sample is heated by a heater, a bias voltage is applied to the metal sample by a bias power supply, and the hydrogen cylinder and the plasma source are turned on, and the metal sample is bombarded with the generated plasma; after the permeation experiment is completed, the first vacuum valve is opened, the second vacuum valve is closed, the standard leak is opened, and the steady-state current value of the mass spectrometer at the current sample temperature and the current ion incident energy is recorded; based on the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer, and the steady-state current value, the steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions is obtained. The embodiment of the present invention can simply and conveniently realize the measurement of the permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions, so that it is not limited by the experimental conditions and operating time of large scientific facilities such as tokamaks. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic structural diagram of a device for measuring hydrogen isotope permeation provided by one embodiment of the present invention;

[0030] Figure 2 This is a structural schematic diagram of a flange sealing structure provided by one embodiment of the present invention;

[0031] Figure 3 This is a product example diagram of a ceramic isolator provided by one embodiment of the present invention;

[0032] Figure 4 This is a deuterium penetration curve of a martensitic steel provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this technical field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] The embodiment of the present invention provides a device for measuring hydrogen isotope permeation, which is used to measure the permeation of hydrogen isotopes through a metal sample under plasma irradiation conditions. Figure 1 FIG2 is a schematic diagram of a device for measuring hydrogen isotope permeation provided by one embodiment of the present invention. The device includes: a mass spectrometer 1, a standard leak 2, a vacuum pump assembly 3, a first vacuum valve 4, a second vacuum valve 5, a plasma discharge chamber 6, a bias power supply 11, a thermocouple 12, a temperature recorder 13, a plasma source 14, and a hydrogen cylinder 15. The plasma discharge chamber 6 includes an isolator 7, a permeation line 8, a heater 9, and a sample stage 10. The sample stage 10 is used to seal and fix the metal sample.

[0035] One end of the isolator 7 is connected to the sample stage 10 through the permeation line 8; the heater 9 is disposed in the permeation line 8 and maintains a preset distance from the sample stage 10; the outlet of the plasma source 14 and the outlet of the hydrogen bottle 15 are both connected to the plasma discharge chamber 6; the bias power supply 11 is connected between the outer shell of the plasma discharge chamber 6 and the sample stage 10; the thermocouple 12 is connected between the sample stage 10 and the temperature recorder 13;

[0036] The other end of the isolator 7 is connected to the mass spectrometer 1 through the first pipeline L1, connected to the standard leak hole 2 through the second pipeline L2, and connected to the vacuum pump group 3 through the third pipeline L3, and the first pipeline L1, the second pipeline L2, and the third pipeline L3 are connected to the other end of the isolator 7 after merging into one pipeline; the first vacuum valve 4 is provided at the end of the second pipeline L2 close to the standard leak hole 2; the second vacuum valve 5 is provided at the end of the merged pipeline L4 close to the isolator 7.

[0037] Specifically, the device is mainly composed of a mass spectrometer 1, a standard leak 2, a vacuum pump group 3, a first vacuum valve 4, a second vacuum valve 5, a plasma discharge chamber 6, an isolator 7, a permeation pipeline 8, a heater 9, a sample stage 10, a bias power supply 11, a thermocouple 12, a temperature recorder 13, a plasma source 14 and a hydrogen cylinder 15, and the isolator 7, the permeation pipeline 8, the heater 9 and the sample stage 10 are arranged inside the plasma discharge chamber 6.

[0038] Further, one end of the isolator 7 (i.e. Figure 1The right end of the isolator 7 shown in the figure is connected to the sample stage 10 through the permeation pipe 8, the heater 9 is arranged at one end of the inside of the permeation pipe 8 close to the sample stage 10, and a preset distance is maintained between the heater 9 and the sample stage 10, the outlet of the plasma source 14 is connected to the plasma discharge chamber 6, the outlet of the hydrogen bottle 15 is connected to the plasma discharge chamber 6, one end of the bias power supply 11 is connected to the outer shell of the plasma discharge chamber 6, the other end of the bias power supply 11 is connected to the sample stage 10, one end of the thermocouple 12 is connected to the sample stage 10, and the other end of the thermocouple 12 is connected to the temperature recorder 13.

[0039] Furthermore, the other end of the isolator 7 (i.e. Figure 1 The left end of the isolator 7 shown in FIG2 is connected to the mass spectrometer 1 through the first pipeline L1, the other end of the isolator 7 is also connected to the standard leak 2 through the second pipeline L2, and the other end of the isolator 7 is also connected to the vacuum pump group 3 through the third pipeline L3, and the end of the first pipeline L1 close to the isolator 7, the end of the second pipeline L2 close to the isolator 7, and the end of the third pipeline L3 close to the isolator 7 are merged into one line, that is, Figure 1 The merged pipeline L4 shown is connected to the other end of the isolator 7 through the merged pipeline L4, which is equivalent to the first pipeline L1, the second pipeline L2 and the third pipeline L3 sharing the merged pipeline L4 to be connected to the isolator 7. The first vacuum valve 4 is arranged on the second pipeline L2, and the first vacuum valve 4 is arranged at the end of the second pipeline L2 close to the standard leak hole 2. The second vacuum valve 5 is arranged on the merged pipeline L4, and the second vacuum valve 5 is arranged at the end of the merged pipeline L4 close to the isolator 7.

[0040] It should be noted that the device can measure the amount of hydrogen isotope penetration through the metal sample in real time under plasma irradiation conditions, and in the actual process of measuring the amount of hydrogen isotope penetration, the sample stage 10 (with a cooling function) is used to seal and fix the metal sample through which the hydrogen isotope is about to penetrate, and the sealed metal sample can separate the plasma discharge chamber 6 from the penetration pipeline 8; the isolator 7 is used to isolate the electrical connection between the metal sample on the sample stage 10 and the device; the heater 9 is used to heat the metal sample on the sample stage 10 to change the sample temperature of the metal sample; the thermocouple 12 is used to measure the sample temperature of the metal sample on the sample stage 10 in real time; the temperature recorder 13 is used to record the sample temperature value measured by the thermocouple 12; the bias power supply 11 is used to apply a bias to the metal sample on the sample stage 10 pressure, and bias voltages of varying magnitudes can be applied to change the ion incident energy of the plasma 16 (generated by the plasma source 14); the plasma source 14 (capable of stable, long-term operation) is configured to generate plasma 16 into the plasma discharge chamber 6 under certain conditions. Preferably, the outlet of the plasma source 14 is disposed opposite the sample stage 10 so that the plasma 16 generated by the plasma source 14 directly bombards the surface of the metal sample on the sample stage 10; the hydrogen cylinder 15 is configured to generate hydrogen into the plasma discharge chamber 6 to provide a source of hydrogen isotopes; the vacuum pump assembly 3 is configured to evacuate the interior of the permeation line 8 to provide a vacuum environment; the standard leak 2 (containing calibration gas) is configured to calibrate the mass spectrometer 1; and the mass spectrometer 1 is configured to measure the amount of hydrogen isotope permeation through the metal sample on the sample stage 10.

[0041] It should be noted that the first vacuum valve 4 is used to control the openness and closeness of the passage between the second pipeline L2 and all other pipelines (the first pipeline L1, the third pipeline L3 and the merged pipeline L4), that is, to control the openness and closeness of the passage between the standard leak hole 2 and the mass spectrometer 1, the vacuum pump group 3, and the permeation pipeline 8; the second vacuum valve 5 is used to control the openness and closeness of the merged pipeline L4, that is, to control the openness and closeness of the passage between the permeation pipeline 8 and the mass spectrometer 1, the standard leak hole 2, and the vacuum pump group 3.

[0042] For example, the metal sample may be a sample made of metal materials such as tungsten, copper, and steel, which is not specifically limited in the embodiment of the present invention.

[0043] Combine Figure 1 As shown, in one of the optional embodiments, the positive pole of the bias power supply 11 is connected to the outer shell of the plasma discharge chamber 6, the negative pole of the bias power supply 11 is connected to the sample stage 10, and the outer shell of the plasma discharge chamber 6 is grounded.

[0044] Specifically, in combination with the above embodiments, in this embodiment, the outer shell of the plasma discharge chamber 6 can be grounded, and the positive pole of the bias power supply 11 can be connected to the outer shell of the plasma discharge chamber 6, and the negative pole of the bias power supply 11 can be connected to the sample stage 10, so that in the process of actually measuring the penetration amount of hydrogen isotopes, different negative bias voltages can be applied to the metal sample on the sample stage 10 using the bias power supply 11, thereby changing the ion incident energy.

[0045] See also Figure 2 , which is a structural schematic diagram of a flange sealing structure provided by one embodiment of the present invention. In one optional embodiment, the sample stage 10 includes a flange sealing structure, and the flange sealing structure includes a knife-edge flange 17, a gasket 18, a cover plate 19 and a fastener 20.

[0046] It should be noted that the fastener 20 includes Figure 2 Bolts 20a and nuts 20b are shown, and there is a pair of bolts 20a and nuts 20b on each side of the flange sealing structure.

[0047] Specifically, in combination with the above embodiments, in this embodiment, the sample stage 10 can use the flange sealing principle to seal the metal sample. In this embodiment, the sample stage 10 includes a flange sealing structure, and when actually sealing the metal sample, the gasket 18 and the metal sample 21 can be placed on the knife-edge flange 17 in sequence, and then the cover 19 is covered. After that, the bolts 20a and nuts 20b on both sides are tightened, and the bolts 20a are used to tighten so that the knife edge of the knife-edge flange 17 is embedded in the sealing gasket 18, thereby forming a tight sealing structure.

[0048] Combine Figure 1 As shown, in one of the optional embodiments, the vacuum pump group 3 is a molecular pump group, and the isolator 7 is a ceramic isolator.

[0049] Specifically, in combination with the above embodiment, in this embodiment, the vacuum pump group 3 can be a molecular pump group, that is, the interior of the permeation pipeline 8 is vacuumed by the molecular pump group, and the isolator 7 can be a ceramic isolator (such as Figure 3 As shown), that is, the electrical connection between the metal sample on the sample stage 10 and the device is cut off by a ceramic isolator.

[0050] It is understandable that, in addition to the molecular pump group and the ceramic isolator, the vacuum pump group 3 may also use other pump groups with vacuum pumping function, and the isolator 7 may also use other isolation devices with isolation function, which is not specifically limited in the embodiment of the present invention.

[0051] Combine Figure 1 As shown, in one of the optional embodiments, the plasma source 14 is a microwave plasma source, a radio frequency plasma source or a hot cathode plasma source.

[0052] Specifically, in combination with the above embodiments, in this embodiment, the plasma source 14 can be a microwave plasma source, a radio frequency plasma source or a hot cathode plasma source, which generates microwave plasma, radio frequency plasma or hot cathode plasma accordingly.

[0053] It is understandable that in addition to the microwave plasma source, the radio frequency plasma source, and the hot cathode plasma source, other types of plasma sources may also be used, and the embodiments of the present invention do not specifically limit this.

[0054] An embodiment of the present invention further provides a method for using a device for measuring hydrogen isotope permeation, which is applied to the device for measuring hydrogen isotope permeation described in any of the above embodiments, comprising:

[0055] The metal sample is sealed and fixed on the sample stage;

[0056] Close the first vacuum valve, open the second vacuum valve, and use the vacuum pump group to vacuum the permeate pipeline;

[0057] When the vacuum level in the permeation line reaches a preset vacuum level threshold, the mass spectrometer is turned on to start a hydrogen isotope permeation experiment. The permeation experiment includes: heating the metal sample with a heater, applying a bias voltage to the metal sample with a bias power supply, and turning on a hydrogen cylinder and a plasma source to bombard the metal sample with the generated plasma.

[0058] After the permeation experiment is completed, the first vacuum valve is opened, the second vacuum valve is closed, the standard leak is opened, and the steady-state current value of the mass spectrometer under the current sample temperature and the current ion incident energy is recorded;

[0059] The steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions is obtained according to the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer and the steady-state current value.

[0060] Specific, combined Figure 1 In this embodiment, the metal sample can be sealed and fixed on the sample stage 10 of the device first, and then the first vacuum valve 4 is closed to block the passage between the standard leak 2 and the mass spectrometer 1, the vacuum pump group 3, and the permeation pipeline 8. The second vacuum valve 5 is opened to connect the permeation pipeline 8 with the mass spectrometer 1 and the vacuum pump group 3, and the vacuum pump group 3 is used to evacuate the permeation pipeline 8 until the vacuum degree in the permeation pipeline 8 reaches a preset vacuum degree threshold, for example, when the vacuum degree reaches 10 -5When Pa, the mass spectrometer 1 is turned on and the hydrogen isotope penetration experiment is started, that is, the metal sample on the sample stage 10 is heated by the heater 9, the sample temperature of the metal sample on the sample stage 10 is measured by the thermocouple 12, and the measured temperature value is recorded in real time by the temperature recorder 13, and the bias power supply 11 is used to apply a bias voltage to the metal sample on the sample stage 10, and the hydrogen bottle 15 is opened to pass hydrogen into the plasma discharge chamber 6, the plasma source 14 is turned on to generate plasma 16, and the generated plasma 16 is used to bombard the metal sample on the sample stage 10 until the penetration of hydrogen isotopes is After the amount reaches a steady state, the hydrogen isotope permeation experiment is terminated, that is, the second vacuum valve 5 is closed to block the channel between the permeation pipeline 8 and the mass spectrometer 1 and the vacuum pump group 3, the first vacuum valve 4 is opened to connect the channel between the standard leak hole 2 and the mass spectrometer 1 and the vacuum pump group 3, and the standard leak hole 2 is opened, and the steady-state current value of the mass spectrometer 1 under the current sample temperature and the current ion incident energy is recorded; finally, based on the standard leak rate of the standard leak hole 2, the steady-state calibration current value and the steady-state current value of the mass spectrometer 1, the steady-state permeation amount of hydrogen isotopes through the metal sample on the sample stage 10 under plasma irradiation conditions is obtained.

[0061] It should be noted that the signal current value of the mass spectrometer 1 is proportional to the penetration amount of the hydrogen isotope. By utilizing the proportional relationship between the steady-state current value of the mass spectrometer 1 under plasma irradiation conditions and the steady-state calibration current value of the mass spectrometer 1, combined with the standard leak rate of the standard leak hole 2, the steady-state penetration amount of the hydrogen isotope through the metal sample on the sample stage 10 under plasma irradiation conditions can be calculated.

[0062] In one optional embodiment, the method further includes:

[0063] Recording the permeation change state of hydrogen isotopes in real time during the permeation experiment;

[0064] judging whether a stable permeation state has been reached according to the permeation change state;

[0065] When it is determined that a stable permeation state is reached, the permeation experiment is terminated.

[0066] Specifically, in combination with the above embodiment, during the hydrogen isotope permeation experiment, this embodiment can also use the mass spectrometer 1 to record in real time the permeation change state of hydrogen isotopes passing through the metal sample during the entire hydrogen isotope permeation experiment, so as to judge whether the permeation amount of hydrogen isotopes has reached a steady state based on the permeation change state of hydrogen isotopes. If it is judged that the permeation amount of hydrogen isotopes has not reached a steady state based on the permeation change state of hydrogen isotopes, the hydrogen isotope permeation experiment is continued; if it is judged that the permeation amount of hydrogen isotopes has reached a steady state based on the permeation change state of hydrogen isotopes, the hydrogen isotope permeation experiment is terminated.

[0067] For example, see Figure 4 As shown in FIG. 1 , a deuterium permeation curve of a martensitic steel provided by an embodiment of the present invention is shown. The metal sample is martensitic steel, and the thickness of the metal sample is 0.75 mm. The martensitic steel on the sample stage 10 is heated by a heater 9 so that the sample temperature of the martensitic steel reaches 256° C. A bias voltage is applied to the martensitic steel on the sample stage 10 by a bias power supply 11 so that the ion incident energy is 15 eV. The mass spectrometer 1 is used to record the permeation change state of deuterium through the martensitic steel in real time from the start of the hydrogen isotope permeation experiment. The corresponding deuterium permeation change curve of the martensitic steel with a thickness of 0.75 mm obtained when the sample temperature is 256° C. and the ion incident energy is 15 eV is shown in FIG. Figure 4 shown, and Figure 4 The horizontal axis is time (unit is s), and the vertical axis is the deuterium permeation flux (i.e. the deuterium permeation amount, unit is atoms / (m 2 s)); according to Figure 4 It can be seen that as the experimental time changes, the deuterium penetration through the martensitic steel will increase rapidly at first, but will eventually reach a stable state and basically no longer change. At this time, the hydrogen isotope penetration experiment can be ended and the steady-state deuterium penetration through the martensitic steel under plasma irradiation conditions can be measured.

[0068] In one optional embodiment, obtaining the steady-state permeation of hydrogen isotopes through the metal sample under plasma irradiation conditions based on the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer, and the steady-state current value specifically includes:

[0069] According to the formula Calculate the steady-state permeation of hydrogen isotopes through the metal sample under plasma irradiation conditions; wherein, J ∞ is the steady-state permeability, S calib is the standard leakage rate of the standard leak hole, A is the effective penetration area of ​​the metal sample, I ∞ is the steady-state current value, I calib is the steady-state calibration current value of the mass spectrometer.

[0070] Specifically, in combination with the above embodiment, when obtaining the steady-state permeation amount of hydrogen isotopes through the metal sample on the sample stage 10 under plasma irradiation conditions based on the standard leak rate of the standard leak 2, the steady-state calibration current value and the steady-state current value of the mass spectrometer 1, the steady-state permeation amount of hydrogen isotopes through the metal sample on the sample stage 10 under plasma irradiation conditions can be directly calculated according to the following formula: ∞ (The unit is atoms per square meter second, that is, atoms / (m 2 s)):

[0071] ;

[0072] Among them, S calib represents the standard leakage rate of the standard leak hole 2 (in molecules per second, i.e. molecules / s), and A represents the effective penetration area of ​​the metal sample (in square meters, i.e. m 2 ), I ∞ It represents the steady-state current value (in amperes, i.e. A) recorded by mass spectrometer 1 at the current sample temperature and current ion incident energy after the hydrogen isotope penetration experiment is completed. calib Indicates the steady-state calibration current value of mass spectrometer 1 (in amperes, i.e. A).

[0073] In one optional embodiment, the method further includes:

[0074] The heater is used to adjust the sample temperature of the metal sample to measure the steady-state permeation of hydrogen isotopes at different sample temperatures.

[0075] Specifically, in combination with the above embodiment, this embodiment can use the heater 9 to heat the metal sample to change the sample temperature of the metal sample, thereby measuring the steady-state permeation of hydrogen isotopes through the metal sample at different sample temperatures.

[0076] It should be noted that each hydrogen isotope permeation experiment can measure the steady-state permeation amount of hydrogen isotopes under a certain sample temperature and a certain ion incident energy. The hydrogen isotope permeation experiment can be repeated multiple times, and in each hydrogen isotope permeation experiment, the heater 9 is used to change the metal sample to a different sample temperature. At this time, the ion incident energy remains unchanged, and the steady-state permeation amount of hydrogen isotopes under the same ion incident energy and different sample temperatures is obtained, thereby obtaining the dependence between the permeation amount of hydrogen isotopes and the sample temperature.

[0077] In one optional embodiment, the method further includes:

[0078] The bias power supply is used to adjust the ion incident energy of the plasma to measure the steady-state permeation of hydrogen isotopes at different ion incident energies.

[0079] Specifically, in combination with the above embodiments, this embodiment can use the bias power supply 11 to change the magnitude of the bias applied to the metal sample to change the ion incident energy of the plasma 16, thereby measuring the steady-state penetration of hydrogen isotopes through the metal sample under different ion incident energies.

[0080] It should be noted that each hydrogen isotope permeation experiment can measure the steady-state permeation amount of hydrogen isotopes under a certain sample temperature and a certain ion incident energy. The hydrogen isotope permeation experiment can be repeated multiple times, and in each hydrogen isotope permeation experiment, the bias power supply 11 is used to change the ion incident energy. At this time, the sample temperature remains unchanged, and the steady-state permeation amount of hydrogen isotopes under the same sample temperature and different ion incident energies is obtained, thereby obtaining the dependence between the permeation amount of hydrogen isotopes and the ion incident energy.

[0081] It is understandable that, with respect to the sample temperature and ion incident energy, in each hydrogen isotope penetration experiment, only the sample temperature or only the ion incident energy may be changed, or both the sample temperature and the ion incident energy may be changed simultaneously, which is not specifically limited in the embodiment of the present invention.

[0082] In summary, the embodiments of the present invention provide a device for measuring hydrogen isotope permeation and a method for using the same. The device includes a mass spectrometer, a standard leak, a vacuum pump group, a first vacuum valve, a second vacuum valve, a plasma discharge chamber, a bias power supply, a thermocouple, a temperature recorder, a plasma source, and a hydrogen cylinder. The plasma discharge chamber includes an isolator, a permeation pipeline, a heater, and a sample stage. The method for using the device includes: sealing a metal sample and fixing it on the sample stage; closing the first vacuum valve, opening the second vacuum valve, and evacuating the permeation pipeline using the vacuum pump group; when the vacuum degree in the permeation pipeline reaches a preset value, the permeation pipeline is evacuated. When the vacuum threshold is reached, the mass spectrometer is turned on and a hydrogen isotope permeation experiment is started, that is, the metal sample is heated by a heater, a bias voltage is applied to the metal sample by a bias power supply, and the hydrogen cylinder and the plasma source are turned on, and the metal sample is bombarded with the generated plasma; after the permeation experiment is completed, the first vacuum valve is opened, the second vacuum valve is closed, the standard leak is opened, and the steady-state current value of the mass spectrometer at the current sample temperature and the current ion incident energy is recorded; based on the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer, and the steady-state current value, the steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions is obtained. The embodiment of the present invention can simply and conveniently realize the real-time measurement of the permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions, and can conveniently change the sample temperature and ion incident energy, and can also work stably for a long time, so that it is not limited by the experimental conditions and operating time of large scientific facilities such as tokamaks.

[0083] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A device for measuring hydrogen isotope permeation, characterized in that: Used to measure the permeation of hydrogen isotopes through a metal sample under plasma irradiation conditions, comprising: a mass spectrometer, a standard leak, a vacuum pump assembly, a first vacuum valve, a second vacuum valve, a plasma discharge chamber, a bias power supply, a thermocouple, a temperature recorder, a plasma source, and a hydrogen cylinder; the plasma discharge chamber comprises an isolator, a permeation line, a heater, and a sample stage, and the sample stage is used to seal and fix the metal sample; One end of the isolator is connected to the sample stage through the permeation line; the heater is disposed in the permeation line and maintains a preset distance from the sample stage; the outlet of the plasma source and the outlet of the hydrogen bottle are both connected to the plasma discharge chamber; the bias power supply is connected between the outer shell of the plasma discharge chamber and the sample stage; the thermocouple is connected between the sample stage and the temperature recorder; The other end of the isolator is connected to the mass spectrometer through a first pipeline, connected to the standard leak hole through a second pipeline, and connected to the vacuum pump group through a third pipeline, and the first pipeline, the second pipeline, and the third pipeline at one end close to the isolator are merged into one pipeline and then connected to the other end of the isolator; the first vacuum valve is arranged at one end of the second pipeline close to the standard leak hole; the second vacuum valve is arranged at one end of the merged pipeline close to the isolator.

2. The device for measuring hydrogen isotope permeation according to claim 1, wherein: The positive electrode of the bias power supply is connected to the outer shell of the plasma discharge chamber, the negative electrode of the bias power supply is connected to the sample stage, and the outer shell of the plasma discharge chamber is grounded.

3. The device for measuring hydrogen isotope permeation according to claim 1, wherein: The sample stage includes a flange sealing structure, which includes a knife-edge flange, a gasket, a cover plate and fasteners.

4. The device for measuring hydrogen isotope permeation according to claim 1, wherein: The vacuum pump group is a molecular pump group, and the isolator is a ceramic isolator.

5. The device for measuring hydrogen isotope permeation according to claim 1, wherein: The plasma source is a microwave plasma source, a radio frequency plasma source or a hot cathode plasma source.

6. A method for using a device for measuring hydrogen isotope permeation, characterized in that: The device for measuring hydrogen isotope permeation according to any one of claims 1 to 5 comprises: The metal sample is sealed and fixed on the sample stage; Close the first vacuum valve, open the second vacuum valve, and use the vacuum pump group to vacuum the permeate pipeline; When the vacuum level in the permeation line reaches a preset vacuum level threshold, the mass spectrometer is turned on to start a hydrogen isotope permeation experiment. The permeation experiment includes: heating the metal sample with a heater, applying a bias voltage to the metal sample with a bias power supply, and turning on a hydrogen cylinder and a plasma source to bombard the metal sample with the generated plasma. After the permeation experiment is completed, the first vacuum valve is opened, the second vacuum valve is closed, the standard leak is opened, and the steady-state current value of the mass spectrometer under the current sample temperature and the current ion incident energy is recorded; The steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions is obtained according to the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer and the steady-state current value.

7. The method for using the device for measuring hydrogen isotope permeation according to claim 6, wherein: The method further comprises: Recording the permeation change state of hydrogen isotopes in real time during the permeation experiment; judging whether a stable permeation state has been reached according to the permeation change state; When it is determined that a stable permeation state is reached, the permeation experiment is terminated.

8. The method for using the device for measuring hydrogen isotope permeation according to claim 6, wherein: The step of obtaining the steady-state permeation amount of hydrogen isotopes passing through the metal sample under plasma irradiation conditions according to the standard leak rate of the standard leak, the steady-state calibration current value of the mass spectrometer, and the steady-state current value specifically includes: According to the formula Calculate the steady-state permeation of hydrogen isotopes through the metal sample under plasma irradiation conditions; wherein, J ∞ is the steady-state permeability, S calib is the standard leakage rate of the standard leak hole, A is the effective penetration area of ​​the metal sample, I ∞ is the steady-state current value, I calib is the steady-state calibration current value of the mass spectrometer.

9. The method for using the device for measuring hydrogen isotope permeation according to claim 6, wherein: The method further comprises: The heater is used to adjust the sample temperature of the metal sample to measure the steady-state permeation of hydrogen isotopes at different sample temperatures.

10. The method for using the device for measuring hydrogen isotope permeation according to claim 6, wherein: The method further comprises: The bias power supply is used to adjust the ion incident energy of the plasma to measure the steady-state permeation of hydrogen isotopes at different ion incident energies.

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