Neutron irradiation simulation device based on high-current pulsed ion beam and rapid evaluation method

Abstract

The neutron irradiation simulation device and rapid evaluation method based on high-current pulsed ion beam belong to the field of nuclear engineering technology. The device includes five parts: bipolar pulse power supply system, high-current pulsed magnetically insulated ion diode system, high-current pulsed electronic grid system, beam measurement and control system, and in-situ differential thermal analysis system. According to the similarity of the energy spectrum of high-energy atoms and primary dissociated atoms (PKA) irradiated by neutrons, the atomic type and kinetic energy, atomic proportion, pulse dose and number of pulses for neutron irradiation simulation are selected. The thermal effect of simulated neutron irradiation is measured by the in-situ differential thermal analysis system, and the difference change of heat energy loss work and thermal radiation work in the cooling process of the sample is analyzed to obtain the annealing recovery energy of irradiation defects, quickly determine the number, density and damage rate of defects in the sample, extrapolate and predict the damage degree of sample materials irradiated by high-dose neutrons, and evaluate the radiation resistance of nuclear structural materials during their service life; it provides an efficient and safe material neutron irradiation performance rapid evaluation technology.

Description

Technical Field

[0001] The present invention is a neutron irradiation simulation device and a rapid evaluation method based on a high-current pulsed ion beam. According to the similarity of the PKA energy spectrum of 0.1-1MeV high-energy atoms and neutron irradiation, a high-current pulsed atomic beam technical equipment with controllable types of atoms, kinetic energy and pulse irradiation dose is invented, and the simulation test conditions and evaluation methods for neutron irradiation materials with different kinetic energies of 1-14MeV in nuclear irradiation environments of various reactor types such as fission reactors and fusion reactors are obtained, which belongs to the field of nuclear engineering technology. Technical Background

[0002] Nuclear energy is the main development trend of clean energy today. Neutron irradiation damage of nuclear structural materials is one of the key issues affecting the safety and stability of nuclear energy devices. In various fission reactors and fusion reactors, neutron irradiation defect damage will cause hardening, embrittlement, swelling and creep of nuclear structural materials, while alloys also include irradiation-induced segregation and phase change. The evaluation of the service behavior of materials under reactor neutron irradiation conditions is difficult, expensive and time-consuming, resulting in a lack of system data, which seriously restricts the development of its failure behavior, law evaluation and life prediction technology, and further limits the research and development of radiation-resistant materials. Therefore, the technology of simulated neutron irradiation outside the reactor such as electron beam and ion beam and the evaluation method of material irradiation damage have been receiving much attention in recent years. Electron irradiation only produces a single Frenkel defect, which is mainly used to study the law of initial point defect generation and understand the related radiation damage mechanism; ion irradiation can produce primary knock-on atom (PKA) collision cascade damage behavior similar to neutron irradiation. In recent years, ion beam technology has been mainly used for neutron irradiation simulation. In 2007, Was et al. published a paper titled "Radiation damage from different particle types" in Radiation Effects in Solids, comparing the effects of protons, Ni + The damage behavior of protons in stainless steel by neutrons is shown in Figure 2. The damage rate of protons varies slightly with depth, but its irradiation dose rate is 10 higher than that of in-pile neutrons. 2 -10 3times, sufficient irradiation dose can be achieved in a shorter time. However, the recoil atomic energy of protons is smaller, resulting in a smaller range of cascade damage, wider cascade spacing and lower damage rate compared to heavier ions or neutrons. Heavy ions have the advantage of high dose rate, which can accumulate higher injection doses in a short time. However, high dose rate brings about larger temperature changes. The influence law and mechanism of irradiation temperature effect of different materials still need further study. In particular, ions are charged particles. After being injected into the material, the collision between ions and atoms is mainly Coulomb interaction. The irradiation PKA damage mechanism is essentially different from that of neutron irradiation, resulting in significant differences in the PKA energy spectrum of irradiated materials. The kinetic energy distribution range of ion irradiation PKA is wide and mainly in the low energy zone below 1keV. The kinetic energy distribution of fission reactor and fusion reactor neutron irradiation PKA is narrow and concentrated in the medium energy zone of 10-100keV. The collision cascades of PKA with different kinetic energy lead to huge differences in irradiation effects such as the formation and evolution dynamics of ion and neutron irradiation defects. Recently, comparative experimental studies on neutron and ion irradiation of metal materials have also observed obvious differences in the irradiation defect characteristics and kinetic behaviors of the two. In 2018, Shu et al. published a paper in Acta Materialia titled "Precipitation in Fe-Cu and Fe-Cu-Mnmodel alloys under irradiation: Dose rate effects" comparing the microstructure of Fe-Cu alloys irradiated with neutrons and 70MeV Fe ions. The size of the precipitated phase by ion irradiation was smaller than that by neutron irradiation, which was explained by the large amount of low-energy PKA produced by ion irradiation. The size of the defect clusters determines its stability and mobility, resulting in differences in the recombination and migration behaviors of point defects under different irradiation dose rates. In contrast, in 2021, Adisa et al. published a paper in Materialia titled "APT characterization and modeling of irradiation-induced Nb-rich nanoclustering in Zr-1.0% Nb alloys", reporting the microstructure of Fe-Cu alloys irradiated with neutrons and 1MeV Kr 2+ The comparative experimental results of ion irradiation of Zr-1.0% Nb alloy found that the nanoclusters produced by ion irradiation are larger and denser than those produced by neutron irradiation. The differences between ion and neutron irradiation observed in the above experimental studies, although the experimental laws are not exactly the same, all confirm the significant differences between the effects of neutron and ion irradiation.

[0003] In 2021, Pushkarev et al. published a paper titled "Comparison of influence of the atom beam and ion beam on the metal target" in Laser and Partial Beams. The study showed that the electron energy loss during the interaction between high-energy atoms and material atoms is much lower than the result of ion irradiation, and more energy is transferred to the colliding atoms to obtain PKA with higher kinetic energy. For pure Fe materials, the PKA energy transfer formation rules of 0.2-0.4 MeV high-energy C atom irradiation and 2-3 MeV neutron irradiation are highly similar. This similarity in the PKA energy spectrum of high-energy atomic irradiation and neutron irradiation can be highly matched by adjusting the atomic type and kinetic energy according to the required neutron energy spectrum conditions, providing a theoretical basis for solving the problem of differences in ion simulation of neutron irradiation. In addition, in the research of high-energy atomic beam devices, in 2018, Belchenko et al. published a review paper "Studies of ion and neutral beam physics and technology at the Budker Institute of Nuclear Physics" in Physics-Uspekhi, summarizing the research progress of ion beam and neutral beam theory and technology at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences. When the kinetic energy of ions exceeds the order of 100 keV, the efficiency of the neutralization mechanism such as the resonant charge transfer collision between conventional ions and gas molecules or the combination of ions with low-energy electrons is very low. Therefore, the development of neutral beam heating sources with kinetic energy of hundreds of keV to MeV required for magnetic confinement fusion reactors has adopted a complex negative ion source system neutralization scheme. To date, there is still a lack of low-cost, high-efficiency high-energy atomic beam devices that produce kinetic energy greater than 100 keV. Summary of the invention

[0004] In order to solve the engineering and technical difficulties of in-pile neutron irradiation simulation, based on the similarity of PKA energy spectrum between high-energy atomic irradiation and neutron irradiation, the present invention provides a neutron irradiation simulation device and rapid evaluation method based on high-current pulsed ion beam, which breaks through the principle limitations of the current ion beam technology for simulating neutron irradiation. Through the differential thermal analysis principle of the corresponding changes in heat energy loss work and thermal radiation work in the neutron irradiation process simulated by high-current pulsed atoms and mixed beams, a new in-situ differential thermal rapid analysis method suitable for quantitative evaluation of the formation law of point defects in simulated neutron irradiated materials is established.

[0005] The technical solution adopted by the present invention is: a neutron irradiation simulation device based on a high-current pulsed ion beam, which consists of five parts: a bipolar pulse power supply system, a high-current pulsed magnetically insulated ion diode system, a high-current pulsed electronic grid system, a beam measurement and control system, and an in-situ differential thermal analysis system. Through the joint operation and control of each part, the irradiation performance evaluation of the material to be tested under neutron irradiation simulation conditions is realized:

[0006] 1) The bipolar pulse power supply system provides power for the operation of the high-current pulse magnetically insulated ion diode, including a DC high-voltage module, a microsecond pulse module, a nanosecond bipolar pulse module, and a bipolar pulse delay control module;

[0007] 2) A high-current pulsed magnetically insulated ion diode system generates a high-current pulsed ion beam, including a magnetically insulated ion diode anode and an extraction cathode, wherein the anode has two structures: a solid anode and a hollow anode, and the hollow anode uses a gas pipeline connected to the anode to transport working gas to the inside of the anode;

[0008] 3) The high-current pulsed electron grid system uses the high-current pulsed ion beam to bombard the metal grid to generate secondary electrons, forming an accompanying high-current pulsed secondary electron beam flow, achieving high-efficiency neutralization of high-energy ions above 0.1MeV, and correspondingly obtaining a high-kinetic energy high-current pulsed atomic beam, including a slot-type metal grid seat and a replaceable metal grid;

[0009] 4) Beam measurement and control system, including pulse voltage measurement module, ion beam measurement module, electron beam measurement module, atom and ion mixed beam measurement module, and neutralization ratio analysis module, which respectively measure the parameters of high-current pulsed ion beam, high-current pulsed electron beam and high-current pulsed atomic beam, analyze the atomic ratio relationship of the neutralization beam, and use it for feedback regulation and control;

[0010] 5) In-situ differential thermal analysis system, including an irradiated sample in-situ temperature measurement module and an irradiated defect in-situ differential thermal analysis software module, for in-situ measurement and analysis of the number and density of irradiated defects of the sample.

[0011] The high-current pulse magnetically insulated ion diode system, under the action of a negative and a positive bipolar pulse applied by a bipolar pulse power supply system, the first arriving negative pulse generates explosive electron emission on the diode anode surface to form plasma, and the first arriving negative pulse output feedback signal is used to delay triggering and control the subsequent positive pulse output, the positive pulse width is 120-140ns, the ions are accelerated and drawn out from the diode cathode grid to form a high-current pulse ion beam; the delay time between the negative pulse and the positive pulse is controllably adjustable in the range of 200-600ns, and the control accuracy is on the order of ±10ns; the anode has two structures, a solid anode and a hollow anode, the solid anode uses its surface explosive electron emission to form a plasma of ionized anode material, the hollow anode uses a pipeline to introduce working gas into the anode, releases from the micropores of the anode working surface and adsorbs on the anode surface, and uses explosive electron emission to form a plasma of ionized adsorbed gas;

[0012] The high current pulse magnetically insulated ion diode system has a background vacuum of no less than 5×10 -3 Pa conditions, when using a solid anode, the anode material is selected from graphite, metal aluminum and other easily ionized solid materials, and the explosive electron emission obtains carbon and aluminum plasma, and correspondingly draws out high-current pulse ion beams of carbon ions and aluminum ions; when using a hollow anode, the anode material is selected from stainless steel and other difficult-to-ionize metal materials, and H2, D2, He, N2, O2, Ar and other working gases are introduced into the anode, and the working gas flow rate and vacuum chamber exhaust rate are controlled so that the anode and cathode discharge areas of the diode obtain 1 to 5×10 -2 Pa working gas pressure ensures that the working gas is adsorbed on the surface of the diode, and the explosive electron emission causes the surface adsorbed gas to undergo explosive desorption and ionization, obtaining an ionized plasma of the adsorbed gas, and correspondingly extracting a high-current pulsed ion beam of gas ions;

[0013] The high-current pulse magnetically insulated ion diode system has a negative pulse voltage for generating plasma adjusted within a range of 100 to 400 kV, and ions of different valence states are obtained by controlling the negative pulse amplitude. The positive pulse voltage for accelerating and extracting ions is 100 to 300 kV, and the output ion kinetic energy is controllably adjustable within a range of 0.1 to 1 MeV. The ion beam pulse width is 120 to 160 ns. When the anode and cathode discharge regions adopt a planar structure, a 10 to 100 cm2 discharge area corresponding to the diode anode discharge region is obtained. 2 The beam spot area with uniform beam current density changes with the distance between the sample and the diode cathode. i 1~50A / cm 2 Range adjustment: When the anode and cathode discharge areas adopt concave surface focusing structure, 50-500A / cm 2 High ion beam current density focused beam with 1~10cm 2 The beam spot area where the beam density is uniformly distributed;

[0014] The high-current pulse electron grid system adopts a single or multiple replaceable metal grids installed on a slot-type metal grid bracket, arranged on the output path of the high-current pulse ion beam, and spaced 10 to 20 cm from the cathode of the diode. The replaceable series of metal grids have different mesh sizes and wire diameters, and the transmittance adjustment range is 20% to 80%. The high-current pulse ion beam bombards the grid to form high-density secondary electrons, and obtains a high-current pulse electron beam with different beam current densities accompanying the high-current pulse ion beam, and realizes efficient electron neutralization of the ion beam passing through the metal grid. The transmittance and number of the metal grid are adjusted to obtain a high-current pulse atomic beam or an atom-ion mixed beam with an atom ratio of 80% to 100%. The atoms retain the high kinetic energy of the ions before neutralization, and the atomic kinetic energy can be adjusted by the ion acceleration voltage and valence state; the beam density J of the atomic beam and the mixed beam is adjusted. n The adjustment range is determined by the corresponding ion beam current density J i and the transmittance α of the metal grid used, which is J n =αJ i ;

[0015] The beam current measurement and control system performs joint measurement and analysis on the parameters of the high-current pulsed ion beam, the high-current pulsed electron beam, and the high-current pulsed atomic beam, and performs feedback adjustment output according to the requirements of the atomic species, atomic kinetic energy, atomic proportion, and pulse irradiation dose required for simulating the neutron irradiation effect; the acceleration voltage measurement module uses a low-inductance aqueous solution voltage divider resistor to measure the acceleration voltage of the ion diode to determine the ion kinetic energy; the ion beam current measurement module uses a Faraday cup with a deflection magnetic field or an electric field to respectively measure the ion beam current density output by the high-current pulsed magnetically insulated ion diode system and the residual ion beam current density after being neutralized by the high-current pulsed electron grid system, and combines the acceleration voltage measurement results to analyze the ion beam current density waveform using the time-of-flight method (TOF) to determine the ion species and the pulse irradiation dose; the electron beam current density measurement module uses a Faraday cup without a deflection field to measure the accompanying high-current pulsed electron beam current density formed by the high-current pulsed ion beam bombarding the grid to determine the negative / positive charge ratio of the neutralized beam;

[0016] The atomic and ion mixed beam current density measurement module uses infrared thermal imaging to measure the peak temperature of the irradiated sample to determine the energy density of the neutralization beam. tot =c v ρΔ[T max -T0] to calculate the energy density of the neutralization beam, c v and ρ are the specific heat capacity and density of the sample, Δ is the thickness of the sample, T maxis the peak temperature, T0 is the initial temperature; the neutralization ratio analysis module determines the ion beam energy density based on the ion acceleration voltage and the residual ion beam current density of the neutralization beam, and obtains the atomic ratio of the neutralization beam. The specific formula is Calculate the energy density of the residual ion beam current of the neutralization beam, where U(t) is the acceleration voltage, t is the pulse width, and J i (t) is the ion beam current density; the proportion of atoms in the neutralized beam is The established correspondence between the negative / positive charge ratio of the neutralization beam and the atomic proportion, the correspondence between the metal grid parameters and the arrangement conditions of the high-current pulsed electron grid system and the negative / positive charge ratio of the neutralization beam, were used to determine the feedback adjustment index of the atomic beam neutralization ratio, and the high-current pulsed electron grid system was regulated to select the required atomic beam parameters. The high-current pulsed magnetically insulated ion diode system obtained an atomic beam pulse irradiation dose of 10 12 ~10 15 n / cm 2 The corresponding pulse dose rate can reach 10 19 ~10 22 n / cm 2 ·s level; in the 0.1~10Hz multi-pulse operation mode, the average dose rate of atomic beam irradiation is 10 11 ~10 16 n / cm 2 ·s level, reaching the neutron dose rate range of current fission and fusion reactor internal components;

[0017] In the in-situ differential thermal analysis system, the in-situ temperature measurement module of the irradiated sample adopts a fast infrared thermometer to measure the temperature change of the irradiated sample in real time, and the temperature measurement response speed is not less than 100ms. For most metal materials with good thermal conductivity, the sample thickness can usually be selected as 100μm; for materials with poor thermal conductivity, the optional thickness of the sample is calculated based on the uniform temperature condition of the sample irradiation heat conduction within the response time of the thermometer, and then the sample thickness is determined in combination with the irradiation temperature measurement verification; the irradiation defect in-situ differential thermal analysis software module is used to analyze the cooling temperature change of the irradiated sample, and the heat energy loss work and thermal radiation work of the irradiated sample cooling process are calculated; the sample heat energy loss work calculation formula is: Among them, J c is the volume energy density of the sample cooling process, according to the formula J c (t) = c v ρ[T c (t)-T0], S is the sample area, T c (t) is the temperature of the sample changing with time during cooling, c v , ρ are the specific heat capacity and density of the sample respectively, T0 is the initial temperature of the sample; the calculation formula for the thermal radiation work of the sample is W ir(t) = S[(ε1+ε2)σ[T c 4 (t)-T a 4 ]], where ε1 and ε2 are the blackness of the irradiated and back sides of the sample, σ is the Stepan-Boltzmann constant, T a is the ambient temperature. Based on the heat difference between the thermal radiation work and the heat energy loss work of the sample, the annealing recovery energy of the irradiated defects of the sample is obtained as Where τ is the characteristic cooling time of the sample, corresponding to the moment when the heat energy loss work of the sample is equal to the heat radiation work; the calculation formula for the number of Frenkel defects generated by the irradiated sample is N d =E an / E d , where E d It is the average dissociation energy of the sample atoms. Combined with the sample area and the atomic range, it determines the irradiation defect density of the material to be tested under the simulated neutron irradiation conditions.

[0018] According to the similarity principle of PKA energy spectrum between high-energy atomic irradiation and neutron irradiation at the order of 100-1000keV, a high-energy pulsed atomic beam device is developed based on the high-current pulsed ion beam technology to obtain a high-energy pulsed atomic beam with controllable atomic species and atomic kinetic energy of 0.1-1MeV, which is used to simulate different neutron energy spectrum irradiation conditions of various types of nuclear reactors and conduct rapid evaluation of material irradiation performance. The evaluation method adopts the following steps:

[0019] 1) Sample preparation: According to the beam spot area with uniform distribution of irradiation beam current density and infrared temperature measurement conditions, the material to be tested with the selected thickness is processed into a foil sample smaller than the beam spot area, and a black matte paint with a thickness of no more than 10 μm is evenly sprayed on the irradiated back side, and fixed on the sample holder with a stainless steel wire with a diameter of no more than 0.1 mm to obtain irradiation conditions where the heat energy loss of heat conduction can be ignored;

[0020] 2) Irradiation test: at no less than 5×10 -3 The irradiation experiment was carried out under a back vacuum of 1.5 Pa. According to the requirements of neutron irradiation simulation conditions, the anode type and material of the high-current pulse magnetically insulated ion diode, as well as the metal grid material, transmittance and grid size parameters were selected to obtain the required atomic and ion mixed beam parameters for irradiation testing. At the same time, an infrared thermometer was used to measure the temperature through the optical glass window of the irradiation chamber to record the temperature changes of the sample during the irradiation process and the cooling process after completion in real time.

[0021] 3) In-situ differential thermal analysis: The infrared thermometer measurement data is imported into the irradiation defect in-situ differential thermal analysis software for processing, and the required analysis results are output, including the sample heat energy loss work W c And thermal radiation work W irThe curve of the change with cooling time is analyzed to determine the heat difference between the two, and the output radiation defect annealing recovery energy E is obtained. an , the total number of point defects, and the defect density and dpa damage degree calculated based on the irradiated area and volume of the sample;

[0022] 4) Irradiation performance evaluation: For the irradiation performance analysis of different materials, two aspects of irradiation performance evaluation results under neutron irradiation simulation conditions are provided. First, the point defect density and DPA damage rate generated under neutron irradiation simulation conditions are analyzed to analyze the irradiation point defect damage formation ability of different materials. Based on the extrapolation of neutron simulation irradiation results, the damage degree of high-dose neutron irradiation of materials during the service life of nuclear reactors is predicted; second, the annealing recovery energy E of irradiation point defects is analyzed. an The ratio E to the initial thermal energy E0 an / E0, where the initial heat energy calculation formula for the sample irradiation is E0 = q tot S, the ratio E / E0 reflects the proportion of defect annealing recovery energy in the irradiation process, and evaluates the point defect recovery ability of the material's irradiation performance.

[0023] The advantages of the present invention are: (1) the device consists of five parts: a high-current pulse magnetically insulated ion diode system, a high-current pulse electronic grid system, a beam measurement and control system, and an in-situ differential thermal analysis system. Through the joint operation and control of each part, a high-energy pulse atomic beam that can simulate neutron irradiation is obtained, and the atomic type, kinetic energy, atomic proportion and pulse irradiation dose are controllably adjustable. In addition, quantitative analysis of sample irradiation defects can be completed in situ. Based on the similarity of the PKA energy spectrum of 0.1-1 MeV high-energy atoms and neutron irradiation, simulated neutron irradiation test and evaluation of 1-14 MeV neutron irradiated materials in various reactor environments such as fission reactors and fusion reactors are realized. The device and evaluation method have clear principles, simple operation, maintenance and protection, short measurement time, and provide efficient and safe rapid evaluation.

[0024] (2) The bipolar pulse power supply system supplies power to the high-current pulse magnetically insulated ion diode system, causing the diode anode to explode and emit electrons to form solid ionized carbon or aluminum plasma or gas ionized hydrogen, deuterium, helium, nitrogen, oxygen, and argon plasma, and then draw out an ion beam; combined with the high-current pulse electron grid system, the ions are neutralized efficiently, and the neutralization ratio is detected by the beam measurement and control system to obtain a pulse irradiation dose of 10 with an atomic ratio of 80-100%, a kinetic energy of 0.1-1 MeV, and a pulse width of 120-160 ns. 12 ~10 15 n / cm 2 , pulse dose rate 10 19 ~10 22 n / cm 2 ·s high-current pulsed atomic and ion mixed beam, in the 0.1-10 Hz multi-pulse operation mode, the average irradiation dose rate is 1011 ~10 16 n / cm 2 ·s level.

[0025] (3) Based on the similarity of the primary ionized atoms (PKA) energy spectra of high-energy atoms and neutron-irradiated samples, the atomic types, atomic proportions and kinetic energy parameters, as well as pulse dose and pulse number are selected to realize single-pulse or multi-pulse neutron irradiation simulation; using the thermal effect of simulated neutron irradiation, the temperature change law of the irradiated sample is measured through an in-situ differential thermal analysis system, the heat energy loss work and thermal radiation work change during the cooling process of the irradiated sample are calculated, the annealing recovery energy of the sample irradiation defects is obtained, the number and density of defects in simulated neutron irradiation are determined, and the irradiation performance of the material is evaluated. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of a neutron irradiation simulation device based on a high-current pulsed ion beam.

[0027] Figure 2 This is a schematic diagram of the main measurement and control unit of the neutron irradiation simulation device based on high-current pulsed ion beam.

[0028] Figure 3 It is a schematic diagram of a neutron irradiation simulation device using a hollow anode high-current pulsed ion source with an arc cylindrical focusing structure.

[0029] Figure 4 It is a schematic diagram of a neutron irradiation simulation device using a planar hollow anode high-current pulsed ion source.

[0030] In the figure: 1. Bipolar pulse power supply, 2. High-current pulse magnetically insulated ion diode system, 3. High-current pulse electronic grid system, 4. Beam measurement and control system, 5. In-situ differential thermal analysis system, 6. Pulse voltage measurement module, 7. Ion beam measurement module, 8. Electron beam measurement module, 9. Atom and ion mixed beam measurement module, 10. Neutralization ratio analysis module, 11. Irradiated sample in-situ temperature measurement module, 12. Irradiated defect in-situ differential thermal analysis software module, 13. High-current pulse atomic beam, 14. Sample, 15. BaF2 glass window, 16. Fast thermal imager. DETAILED DESCRIPTION

[0031] The details of the present invention are further described below in conjunction with specific embodiments:

[0032] Figure 1 , 2The overall structure of the neutron irradiation simulation device of high-current pulsed ion beam and the schematic diagram of the main measurement and control unit are given respectively. The high-energy pulsed atomic beam generation of the device is mainly composed of four parts: a bipolar pulse power supply 1, a high-current pulsed magnetically insulated ion diode system 2, a high-current pulsed electronic grid system 3, and a beam measurement and control system 4. Through the joint operation and control of each part, a high-energy pulsed atomic beam that can simulate neutron irradiation is obtained, and the quantitative analysis of the irradiation point defects of the material to be tested is completed through the in-situ differential thermal analysis system 5, thereby realizing the rapid evaluation of the irradiation performance of the material under the simulated in-pile neutron irradiation conditions.

[0033] The beam current measurement and control system is mainly composed of a pulse voltage measurement module 6, an ion beam current measurement module 7, an electron beam current measurement module 8, and an atom and ion mixed beam current measurement module 9. Among them, the pulse voltage measurement module 6 uses a water resistance voltage divider to measure the diode acceleration voltage; the ion beam current measurement module 7 uses a Faraday cup to measure the ion beam current density; the electron beam current measurement module 8 uses a Faraday cup without a deflection magnetic field or electric field to measure the electron beam current density after electron neutralization, and adds it to the absolute value of the residual ion beam current density of the neutralized beam to obtain the total electron beam current density of the neutralized beam; the atom and ion mixed beam current measurement module 9 uses infrared thermal imaging to measure, and the neutralization ratio analysis module 10 uses the formula Calculate the neutralization ratio, where q tot is the beam energy density after neutralization, q i Neutralization beam residual ion beam energy density.

[0034] The in-situ differential thermal analysis system 5 is mainly composed of an irradiated sample in-situ temperature measurement module 11 and an irradiated defect in-situ differential thermal analysis software module 12. The irradiated sample in-situ temperature measurement module 11 includes a foil sample 14 of selected thickness to be tested, a BaF2 glass window 15, and an infrared thermometer 16, which records the temperature change of the sample during the irradiation process of the high-energy pulse atomic beam 13. The infrared thermometer measurement data is imported into the irradiated defect in-situ differential thermal analysis software for processing, and the required analysis results are output, including the sample heat energy loss work W that changes with time. c And thermal radiation work W ir Curve, using the heat difference between the two to calculate the irradiation defect annealing recovery energy E an , the total number of point defects, the defect density and DPA damage degree calculated based on the area and volume of the irradiated sample, determine the material irradiation point defect damage formation ability and the point defect recovery ability of the irradiated material under neutron irradiation simulation conditions, and predict the irradiation performance of the material during its service life in a nuclear radiation environment based on the extrapolation of neutron simulation irradiation results.

[0035] Example 1

[0036] The 2.0 MeV neutron simulated irradiation performance test of Fe samples was carried out using a high-current pulsed nitrogen atomic beam with a kinetic energy of 220 keV. The pulse energy density was controlled at 1-4 J / cm 2 The measured dose range of neutron simulation irradiation with a pulse width of 140 ns is 1.5 to 6.5 × 10 13 n / cm 2 , the pulse dose rate is about 1.1~4.6×10 20 n / cm 2 ·s. The specific steps are as follows:

[0037] 1) Sample preparation: Pure Fe was processed into a circular foil sample with a diameter of 10 mm and a thickness of 0.1 mm. A layer of black matte paint with a thickness of about 10 μm was evenly sprayed on the back of the sample. A stainless steel wire with a diameter of 0.05 mm was used to fix the sample. The beam spot area of ​​the focused atomic beam was selected to be larger than that of the sample to ensure uniform irradiation of the beam and negligible heat energy loss due to heat conduction.

[0038] 2) Irradiation experiment: According to the required nitrogen atoms and ion types, a hollow anode high-current pulsed ion source with an arc cylindrical focusing structure was selected. The diode anode material was AISI 304 stainless steel, and the background vacuum was 2×10 -3 Pa, the N2 flow rate into the diode anode was 10 ml / min, and the working pressure of the diode area was controlled to be 2×10 -2 Pa, according to the required neutralization atomic ratio, an AISI 304 stainless steel grid with a mesh side length of 0.38mm and a transmittance of 0.48 was selected to obtain a high-energy pulsed nitrogen atomic beam with a neutralization ratio of 90% for irradiation testing; an infrared thermometer with a response speed of 100ms was used to measure the temperature outside the irradiation sample room through the BaF2 optical glass window, and the temperature change of the sample during the irradiation process was recorded in real time;

[0039] 3) In-situ differential thermal analysis: The defects generated during the pulse beam irradiation process and the annealing recovery process that accompanies the cooling process lead to differences between the input heat energy and the thermal radiation dissipation energy of different samples. The data recorded by the infrared thermometer was imported into the irradiation defect in-situ differential thermal analysis software for processing, and the results showed that the 1-4 J / cm 2 Within the energy density range, the irradiation defect annealing recovery energy E of pure Fe sample an It is 0.124~0.696J.

[0040] 4) Irradiation performance evaluation: Using the irradiation defect in-situ differential thermal analysis software, the defect density of pure Fe irradiated by pulse, the Fe atomic displacement energy E d is 40eV, the total number of point defects N d 1.9×10 16 ~1.1×10 17, the defect surface density is 2.4×10 16 ~1.4×10 17 / cm 2 The dpa value of radiation damage is 0.0110~0.0280, E an / E0 is between 22.4% and 31.8%; based on the experimental results of neutron simulation irradiation of Fe samples, it is predicted that in a nuclear reactor with a service life of 60 years, 1×10 21 n / cm 2 Under the irradiation dose conditions, the irradiation damage is about 310dpa.

[0041] Example 2

[0042] The Ni sample was tested for 2.0 MeV neutron simulated irradiation performance using a 220 keV high-current pulsed nitrogen atomic beam. The pulse energy density was controlled at 0.5 to 1 J / cm 2 The measured dose range of neutron simulation irradiation with a pulse width of 140 ns is 0.7 to 1.6 × 10 13 n / cm 2 , the pulse dose rate is about 0.5~1.1×10 20 n / cm 2 ·s. The specific steps are as follows:

[0043] 1) Sample preparation: A pure Ni foil with a thickness of 0.1 mm was processed into a sample with a length of 50 mm and a width of 30 mm. A layer of black matte paint with a thickness of about 10 μm was evenly sprayed on the back of the sample. A stainless steel wire with a diameter of 0.1 mm was used to fix the sample. The beam spot area of ​​the unfocused atomic beam irradiation was selected to be larger than that of the sample to ensure uniform irradiation of the beam and negligible heat energy loss caused by heat conduction.

[0044] 2) Irradiation experiment: According to the required nitrogen atoms and ion types, a planar hollow anode high-current pulsed ion source was selected. The diode anode material was AISI 304 stainless steel. The background vacuum was 2×10 -3 Pa, the N2 flow rate into the diode anode was 10 ml / min, and the working pressure of the diode area was controlled to be 2×10 -2 Pa, according to the required neutralization atomic ratio, an AISI 304 stainless steel grid with a mesh side length of 0.38mm and a transmittance of 0.48 was selected to obtain a high-energy pulsed nitrogen atomic beam with a neutralization ratio of 90% for irradiation testing; an infrared thermometer with a response speed of 100ms was used to measure the temperature outside the irradiation sample room through the BaF2 optical glass window, and the temperature change of the sample during the irradiation process was recorded in real time;

[0045] 3) In-situ differential thermal analysis: The defects generated during the pulse beam irradiation process and the annealing recovery process that accompanies the cooling process lead to differences between the input heat energy and the thermal radiation dissipation energy of different samples. The data recorded by the infrared thermometer was imported into the irradiation defect in-situ differential thermal analysis software for processing, and the results showed that 0.5~1J / cm 2 The irradiation defect annealing recovery energy E of pure Ni sample within the energy density range an It is 0.037~0.108J.

[0046] 4) Irradiation performance evaluation: Using the irradiation defect in-situ differential thermal analysis software, the pulse irradiated pure Ni defect density and Ni atomic displacement energy E were quantitatively calculated. d is 36eV, and the total number of point defects is 6.4×10 15 ~1.9×10 16 , the defect surface density is 8.0×10 15 ~2.4×10 16 / cm 2 , the corresponding dpa is 0.0036~0.0108, E an / E0 is between 9.7% and 11.9%. Based on the experimental results of neutron simulated irradiation of Ni samples, it is predicted that in a nuclear reactor with a service life of 60 years, 1×10 21 n / cm 2 Under the irradiation dose conditions, the irradiation damage is about 115dpa.

[0047] Example 3

[0048] The Ti sample was tested for 1.8 MeV neutron simulated irradiation performance using a 220 keV high-current pulsed carbon atom beam. The pulse energy density was controlled at 1-4 J / cm 2 The measured dose range of neutron simulation irradiation with a pulse width of 140 ns is 1.9×10 13 ~1.1×10 14 n / cm 2 , the pulse dose rate is about 1.4~7.9×10 20 n / cm 2 ·s. The specific steps are as follows:

[0049] 1) Sample preparation: Pure Ti was processed into a circular foil sample with a diameter of 10 mm and a thickness of 0.1 mm. A layer of black matte paint with a thickness of about 10 μm was evenly sprayed on the back of the sample. A stainless steel wire with a diameter of 0.05 mm was used to fix the sample. The beam spot area of ​​the focused atomic beam was selected to be larger than that of the sample to ensure uniform irradiation of the beam and negligible heat energy loss due to heat conduction.

[0050] 2) Irradiation experiment: According to the required nitrogen atoms and ion types, a solid anode high-current pulsed ion source with an arc cylindrical focusing structure was selected. The diode anode material was graphite, and the background vacuum was 5×10 -3 Under Pa conditions, according to the required neutralized atomic ratio, an AISI304 stainless steel grid with a mesh side length of 0.38 mm and a transmittance of 0.48 was selected to obtain a high-energy pulsed carbon atom beam with a neutralization ratio of about 87% for irradiation testing; an infrared thermometer with a response speed of 100ms was used to measure the temperature outside the irradiation sample room through the BaF2 optical glass window, and the temperature change of the sample during irradiation was recorded in real time.

[0051] 3) In-situ differential thermal analysis: The defects generated during the pulse beam irradiation process and the annealing recovery process that accompanies the cooling process lead to differences between the input heat energy and the thermal radiation dissipation energy of different samples. The data recorded by the infrared thermometer was imported into the irradiation defect in-situ differential thermal analysis software for processing, and the results showed that the 1-4 J / cm 2 Within the energy density range, the irradiation defect annealing recovery energy E of pure Ti sample an It is 0.122~0.825J.

[0052] 4) Irradiation performance evaluation: Using the irradiation defect in-situ differential thermal analysis software, the pulse irradiation defect density and Ti atomic displacement energy E were quantitatively calculated. d is 69eV, the total number of point defects N d 1.1~7.6×10 16 , the defect surface density is 1.4~9.6×10 16 / cm 2 , the corresponding dpa is 0.0069~0.0466, E an / E0 is between 14.7% and 31.3%. Based on the experimental results of neutron simulated irradiation of Ti samples, it is predicted that the 1×10 21 n / cm 2 Under the irradiation dose conditions, the irradiation damage is about 231dpa.

[0053] Example 4

[0054] The nuclear grade AISI304 austenitic stainless steel sample was tested for 2.0 MeV neutron simulated irradiation performance using a 250 keV high current pulsed carbon atom beam. The pulse energy density was controlled at 1-4 J / cm 2 The measured dose range of neutron simulation irradiation with a pulse width of 140 ns is 0.46~8.55×10 13 n / cm 2 , the pulse dose rate is about 0.33~6.1×10 20 n / cm 2 ·s. The specific steps are as follows:

[0055] 1) Sample preparation: Process nuclear-grade AISI304 austenitic stainless steel into a circular foil sample with a diameter of 10 mm and a thickness of 0.1 mm. Spray a layer of black matte paint with a thickness of about 10 μm evenly on the back of the sample. Use a stainless steel wire with a diameter of 0.05 mm to fix it. Select a focused atomic beam irradiation spot area larger than the sample to ensure uniform irradiation of the beam and negligible heat energy loss due to heat conduction.

[0056] 2) Irradiation experiment: According to the required nitrogen atoms and ion types, a solid anode high-current pulsed ion source with an arc cylindrical focusing structure was selected. The diode anode material was graphite, and the background vacuum was 5×10 -3 Under Pa conditions, according to the required neutralized atomic ratio, an AISI304 stainless steel grid with a mesh side length of 0.38 mm and a transmittance of 0.48 was selected to obtain a high-energy pulsed carbon atom beam with a neutralization ratio of about 87% for irradiation testing; an infrared thermometer with a response speed of 100ms was used to measure the temperature outside the irradiation sample room through the BaF2 optical glass window, and the temperature change of the sample during irradiation was recorded in real time.

[0057] 3) In-situ differential thermal analysis: The defects generated during the pulse beam irradiation process and the annealing recovery process that accompanies the cooling process lead to differences between the input heat energy and the thermal radiation dissipation energy of different samples. The data recorded by the infrared thermometer was imported into the irradiation defect in-situ differential thermal analysis software for processing, and the results showed that the 1-4 J / cm 2 The irradiation defect annealing recovery energy E of AISI304 austenitic stainless steel sample within the energy density range an It is 0.13~1.5J.

[0058] 4) Irradiation performance evaluation: Using the irradiation defect in-situ differential thermal analysis software, the pulse irradiation defect density and the atomic displacement energy E of Fe-based materials were quantitatively calculated. d is 40eV, the total number of point defects N d 0.48~2.3×10 17 , the defect surface density is 0.62~2.9×10 17 / cm 2 , the corresponding dpa is 0.0096~0.1408, E an / E0 is between 46.0% and 61.9%. Based on the experimental results of neutron simulation irradiation of nuclear grade AISI304 austenitic stainless steel samples, it is predicted that the 1×10 21 n / cm 2 Under the irradiation dose conditions, the irradiation damage is about 510dpa.

Claims

1. A neutron irradiation simulation device based on high-current pulsed ion beam, characterized in that: The device comprises a bipolar pulse power supply system (1), a high-current pulse magnetically insulated ion diode system (2), a high-current pulse electronic grid system (3), a beam measurement and control system (4), and an in-situ differential thermal analysis system (5). Through the joint operation and control of each part, the irradiation performance evaluation of the material to be tested under neutron irradiation simulation conditions is achieved: The bipolar pulse power supply system (1) provides electric energy for the operation of the high-current pulse magnetically insulated ion diode system (2), and comprises a DC high-voltage module, a microsecond pulse module, a nanosecond bipolar pulse module and a bipolar pulse delay control module; The high-current pulsed magnetically insulated ion diode system (2) generates a high-current pulsed ion beam, comprising a magnetically insulated ion diode anode and an extraction cathode; wherein the magnetically insulated ion diode anode has two structures: a solid anode and a hollow anode, and the hollow anode uses a gas pipeline connected to the anode to transport working gas into the anode; The high-current pulsed electron grid system (3) utilizes the high-current pulsed ion beam to bombard the metal grid to generate secondary electrons, thereby forming an accompanying high-current pulsed secondary electron beam flow, achieving high-efficiency neutralization of high-energy ions above 0.1 MeV, and obtaining a high-current pulsed atomic beam. It uses a replaceable metal grid installed on a slot-type metal grid seat; The beam current measurement and control system (4) comprises a pulse voltage measurement module (6), an ion beam current measurement module (7), an electron beam current measurement module (8), an atom and ion mixed beam current measurement module (9) and a neutralization ratio analysis module (10); the ion beam current measurement module (7), the electron beam current measurement module (8) and the atom and ion mixed beam current measurement module (9) respectively measure the beam current density parameters of the high-current pulsed ion beam, the high-current pulsed electron beam and the high-current pulsed atomic beam; and the neutralization ratio analysis module (10) analyzes the atomic ratio relationship of the neutralized beam for feedback regulation and control; The in-situ differential thermal analysis system (5) comprises an irradiated sample in-situ temperature measurement module (11) and an irradiated defect in-situ differential thermal analysis software module (12), and performs in-situ measurement and analysis on the number and density of irradiated defects of the sample.

2. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1, characterized in that: The high-current pulsed magnetically insulated ion diode system (2) is subjected to the action of a negative and a positive bipolar pulse applied by a bipolar pulse power supply system. The first arriving negative pulse generates explosive electron emission on the diode anode surface to form plasma. The first arriving negative pulse outputs a feedback signal to delay triggering and control the subsequent positive pulse output. The positive pulse width is 120-140 ns, and the ions are accelerated and drawn out from the diode cathode grid to form a high-current pulsed ion beam. The delay time between the negative pulse and the positive pulse is controllably adjustable in the range of 200-600 ns, and the control accuracy is on the order of ±10 ns. The magnetically insulated ion diode anode has two structures: a solid anode and a hollow anode. The solid anode uses explosive electron emission on its surface to form plasma of ionized anode material, while the hollow anode uses a pipeline to introduce working gas into the anode, releases it from the micropores on the anode working surface and adsorbs it on the anode surface, and uses explosive electron emission to form plasma of ionized adsorbed gas.

3. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1 is characterized in that: The high-current pulse magnetically insulated ion diode system (2) has a background vacuum degree of no less than 5 × 10 -3 Working under Pa conditions; When a solid anode is used, the anode material is a solid material that is easily ionized; the explosive electron emission causes the anode material to be ionized, obtaining the plasma of the anode material and leading to a corresponding high-current pulsed ion beam; When a hollow anode is used, the anode material is a metal material that is difficult to ionize. The working gas H2, D2, He, N2, O2 or Ar is introduced into the anode. The working gas flow rate and the vacuum chamber pumping rate are controlled so that the discharge area of ​​the cathode and cathode of the diode can reach 1~5 × 10 -2 Pa working gas pressure, the working gas is adsorbed on the surface of the diode, and the explosive electron emission causes the adsorbed gas to undergo explosive desorption and ionization, thereby obtaining an ionized plasma of the adsorbed gas and correspondingly eliciting a high-current pulsed ion beam of gas ions.

4. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1, characterized in that: The negative pulse voltage of the plasma generated by the high-current pulse magnetically insulated ion diode system (2) is adjusted within the range of 100-400 kV, and ions of different valence states are obtained by controlling the negative pulse amplitude. The positive pulse voltage for accelerating and extracting ions is 100-300 kV, and the output ion kinetic energy is controllably adjustable within the range of 0.1-1 MeV. The ion beam pulse width is 120-160 ns. When the anode and cathode discharge regions adopt a planar structure, a 10~100 cm2 area corresponding to the anode discharge region of the diode is obtained. 2 The beam spot area with uniform beam current density changes. The distance between the sample and the cathode of the diode changes. J i 1~50 A / cm 2 Range adjustment; When the anode and cathode discharge regions adopt a concave focusing structure, 50~500 A / cm 2 High ion beam current density focused beam with 1~10 cm 2 The beam spot area where the beam density is uniformly distributed.

5. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1, characterized in that: The high-current pulsed electron grid system (3) uses a single or multiple replaceable metal grids, which are installed on a slot-type metal grid bracket and arranged on the output path of the high-current pulsed ion beam, and are spaced 10 to 20 cm from the cathode of the diode. The replaceable series of metal grids have different mesh sizes and wire diameters, and the transmittance adjustment range is 20% to 80%. The high-current pulsed ion beam bombards the grid to form high-density secondary electrons, thereby obtaining an accompanying high-current pulsed electron beam, achieving efficient electron neutralization of the ion beam passing through the metal grid, adjusting the transmittance and number of the metal grid, and obtaining a high-current pulsed atomic beam or a mixed beam of atoms and ions with an atomic ratio of 80% to 100%. The atoms retain the high kinetic energy of the ions, and the atomic kinetic energy is adjusted by the ion acceleration voltage and valence state. Beam current density of atomic beam and hybrid beam J n The adjustment range is determined by the beam current density of the corresponding high-current pulsed ion beam J i and the transmittance of the metal grid used α Decide for J n = αJ i .

6. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1, characterized in that: The beam measurement and control system (4) performs joint measurement and analysis on the parameters of the high-current pulsed ion beam, the high-current pulsed electron beam, and the high-current pulsed atomic beam, and performs feedback adjustment output of the parameters of atomic type, atomic kinetic energy, atomic ratio, and pulse irradiation dose based on the atomic beam parameters required for neutron irradiation simulation determined by the PKA energy spectrum similarity; The pulse voltage measurement module uses a low-inductance aqueous solution voltage divider resistor to measure the accelerating voltage of the ion diode to determine the kinetic energy of the ions; The ion beam current measurement module uses a Faraday cup with a deflection magnetic field or electric field to measure the ion beam current density output by the high-current pulse magnetic insulation ion diode system and the residual ion beam current density after being neutralized by the high-current pulse electronic grid system. Combined with the acceleration voltage measurement results, the flight time method is used to analyze the ion beam current density waveform to determine the ion type and pulse irradiation dose. The electron beam current density measurement module uses a Faraday cup without a deflection field to measure the high-current pulse electron beam current density formed by the high-current pulse ion beam bombarding the grid, and determine the negative / positive charge ratio of the neutralized beam; The atomic and ion mixed beam current density measurement module uses infrared thermal imaging to measure the peak temperature of the irradiated sample and determine the energy density of the neutralization beam. Specifically, the energy density of the neutralization beam is calculated by formula (I): Formula (I) in, c v and ρ are the specific heat capacity and density of the sample respectively, Δ is the thickness of the sample, T max is the peak temperature, T 0 is the initial temperature; The neutralization ratio analysis module determines the ion beam energy density based on the ion acceleration voltage and the residual ion beam current density of the neutralization beam, and obtains the atomic ratio of the neutralization beam. Specifically, the energy density of the residual ion beam current of the neutralization beam is calculated by formula (II): Formula (II) in, U ( t ) is the accelerating voltage, t is the pulse width, J i ( t ) is the ion beam current density; the proportion of atoms in the neutralized beam is ; By using the established correspondence between the negative / positive charge ratio of the neutralization beam and the atomic proportion, the correspondence between the metal grid parameters and the arrangement conditions of the high-current pulsed electron grid system and the negative / positive charge ratio of the neutralization beam, the feedback adjustment index of the atomic beam neutralization ratio is determined, the high-current pulsed electron grid system is selected, and the output required atomic beam parameters are adjusted; The high-current pulsed magnetically insulated ion diode system can obtain an atomic beam pulse irradiation dose of 10 12 ~10 15 n / cm 2 The corresponding pulse dose rate can reach 10 19 ~10 22 n / cm 2 ·s level; in the 0.1~10 Hz multi-pulse operation mode, the average dose rate of atomic beam irradiation is 10 11 ~10 16 n / cm 2 ·s level.

7. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 1, characterized in that: The irradiated sample in-situ temperature measurement module (11) of the in-situ differential thermal analysis system (5) uses a fast infrared thermometer to measure the temperature change of the irradiated sample in real time, and the temperature measurement response speed is not less than 100 ms; The irradiation defect in-situ differential thermal analysis software module (12) is used to analyze the cooling temperature change of the irradiated sample, and the heat energy loss work and thermal radiation work of the irradiated sample cooling process are calculated; The calculation formula of the heat energy loss of the sample is: Formula (III) in, J c is the volume energy density of the sample cooling process, S is the sample area, T c ( t ) is the temperature of the sample changing with time during cooling, c v , ρ are the specific heat capacity and density of the sample, Δ is the sample thickness, T 0 is the initial temperature of the sample; J c The calculation formula is: Formula (IV) The calculation formula of the thermal radiation work of the sample is: Formula (V) Among them, ε1 and ε2 are the blackness of the irradiated side and the back side of the sample respectively, σ is the Stepan-Boltzmann constant, T a is the ambient temperature; According to the heat difference between the thermal radiation work and the heat energy loss work of the sample, the annealing recovery energy of the irradiated defects of the sample is obtained: Formula (VI) Among them, τ is the characteristic cooling time of the sample, corresponding to the moment when the heat energy loss work of the sample is equal to the heat radiation work; The calculation formula for the number of Frenkel defects generated by sample irradiation is: Formula (VII) in, E d It is the average ionization energy of the sample atoms. Combined with the sample area and atomic range, it determines the irradiation defect density of the material to be tested under the simulated neutron irradiation conditions.

8. The neutron irradiation simulation device based on high-current pulsed ion beam according to claim 7, characterized in that: The method for determining the sample thickness is to calculate the optional sample thickness based on the uniform temperature condition of the sample radiation heat conduction within the response time of the thermometer, and then combine it with the radiation temperature measurement verification, and take the sample with the maximum thickness from the optional thicknesses after verification.

9. The rapid evaluation method of a neutron irradiation simulation device based on a high-current pulsed ion beam according to claim 1, characterized in that: According to the similarity principle of PKA energy spectrum between high-energy atomic irradiation and neutron irradiation at the order of 0.1~1MeV, a high-energy pulsed atomic beam device is developed based on the high-current pulsed ion beam technology to obtain a high-energy pulsed atomic beam with controllable atomic species and atomic kinetic energy of 0.1~1 MeV, which is used to simulate different neutron energy spectrum irradiation conditions of various types of nuclear reactors and conduct rapid evaluation of material irradiation performance; the evaluation method adopts the following steps: 1) Sample preparation: According to the beam spot area with uniform distribution of irradiation beam current density and infrared temperature measurement conditions, the material to be tested with the selected thickness is processed into a foil sample smaller than the beam spot area, and a black matte paint with a thickness of no more than 10 μm is evenly sprayed on the irradiated back side, and fixed on the sample holder with a stainless steel wire with a diameter of no more than 0.1 mm to obtain irradiation conditions where the heat energy loss of heat conduction can be ignored; 2) Irradiation test: at no less than 5 × 10 -3 The irradiation experiment was carried out under a back vacuum of 1.5 Pa. According to the requirements of neutron irradiation simulation conditions, the anode type and material of the high-current pulse magnetically insulated ion diode, the metal grid material, transmittance and grid size parameters were selected to obtain the required atomic and ion mixed beam parameters for irradiation testing. At the same time, an infrared thermometer was used to measure the temperature through the optical glass window of the irradiation room to record the temperature changes of the sample during the irradiation process and the cooling process after completion in real time. 3) In-situ differential thermal analysis: The infrared thermometer measurement data is imported into the irradiation defect in-situ differential thermal analysis software for processing, and the required analysis results are output, including the sample heat energy loss work W c Thermal radiation work W ir The curve of the change with cooling time is analyzed to determine the heat difference between the two, and the output of irradiation defect annealing recovery energy E an , the total number of point defects, and the defect density and dpa damage degree calculated based on the irradiated area and volume of the sample; 4) Irradiation performance evaluation: For the irradiation performance analysis of different materials, two aspects of irradiation performance evaluation results are provided under neutron irradiation simulation conditions: i) The number and density of defects in the sample under neutron irradiation simulation conditions and their DPA damage rate, analyze the damage formation ability of irradiation point defects of different materials, and predict the damage degree of high-dose neutron irradiation of the material during its service life in the nuclear environment based on the extrapolation of the results of neutron simulation irradiation samples; ii) Analysis of irradiation point defect annealing recovery energy E an With initial heat E Ratio of 0 E / E 0, where the initial heat energy calculation formula of the sample irradiation is: Formula (VIII) is the energy density of the neutralization beam; the ratio E an / E 0 reflects the proportion of defect annealing recovery energy in the irradiation process, and evaluates the point defect recovery ability of the material's irradiation performance.

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