A nuclear power material irradiation damage mitigation system and evaluation method

Abstract

This invention relates to a radiation damage mitigation system and evaluation method for nuclear power materials, comprising: a sample clamp module to fix the sample to be treated; an external field heating module to provide a target space region for installation to the sample clamp module and to perform external field heating on the target space region; a vacuum system module to control the target space region in the external field heating module to enter a high vacuum environment; and a pulse power supply module to generate a pulse current to perform high-energy pulsed electric field mitigation treatment on the sample to be treated. This invention, through this radiation damage mitigation system, can protect ion-irradiated damaged samples from surface oxidation under high-energy treatment conditions, and can also monitor temperature changes in real time during sample treatment. For small-sized samples, high-parameter electric pulse treatment experiments can be carried out, aiding in related radiation damage mitigation research. Simultaneously, it provides a quantitative evaluation of the radiation damage mitigation effect, offering technical methods and references for the life extension theory and engineering applications of nuclear power component materials.

Description

Technical Field

[0001] This invention relates to the field of nuclear power radiation technology, and more specifically, to a system and method for mitigating radiation damage to nuclear power materials. Background Technology

[0002] The safe operation of critical components in nuclear power plants is a core element for long-term safe and efficient operation. Under long-term service conditions, nuclear power materials suffer damage and aging, leading to performance degradation in components. The aging of critical components has a significant impact on the safe operation of nuclear power plants. The service life of a nuclear power plant largely depends on the lifespan of "non-replaceable equipment," such as the reactor pressure vessel (RPV), which is the only non-replaceable component within the reactor. During operation, the RPV is subjected to intense neutron radiation, causing hardening / embrittlement. Studies show that after neutron irradiation, RPV steel develops a series of microstructural defects, leading to changes in its mechanical properties (such as increased yield strength, decreased toughness, and increased brittleness). The embrittlement sources mainly include dislocation loops and solute atom clusters. Irradiation embrittlement reduces the service safety of the RPV. Extending the service life of nuclear power plants is one of the most pressing issues in nuclear power engineering. This is achieved through life assessment, aging management, and technical maintenance of "non-replaceable equipment," ultimately extending its service life.

[0003] Current research on mitigation of material irradiation damage mainly focuses on annealing, with limited research on high-energy external electric pulse treatment methods. Annealing is less effective at lower temperatures, posing a safety risk for nuclear power plant component repair, and existing technologies lack effective methods for assessing the degree of irradiation damage mitigation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a system and evaluation method for mitigating radiation damage to nuclear power materials, addressing the problems existing in the prior art.

[0005] The technical solution adopted by this invention to solve its technical problem is: constructing a nuclear power material radiation damage mitigation system, comprising: A sample clamp module, which is used to fix the sample to be processed; An external heating module is provided to the sample clamp module to provide a target space area for installation and to perform external heating on the target space area. A vacuum system module, which is used to control the target space region in the external heating module to enter a high vacuum environment; A pulse power supply module is used to generate pulse current to perform high-energy pulse electric field relief treatment on the sample to be treated.

[0006] In the nuclear power material irradiation damage mitigation system of the present invention, the pulse power supply module includes: an industrial-grade pulse power supply, a positive cable conductor, and a negative cable conductor; The industrial-grade pulse power supply generates the pulse current by adjusting the output current state according to the pulse parameters set. The positive cable wires are respectively connected to the sample clamp module and connected to the sample to be processed.

[0007] In the nuclear power material irradiation damage mitigation system of the present invention, the external heating module includes: a tubular flash furnace and an industrial chiller; The tubular flash furnace is equipped with a vacuum tube interface and a lifting base device; the vacuum tube interface is connected to the vacuum system module, and the lifting base device is used to install the sample clamp module. The industrial chiller is connected to the lifting base device via a circulating water cooling pipe, and is used to provide circulating cooling water through the circulating water cooling pipe to cool the tubular flash furnace.

[0008] In the nuclear power material irradiation damage mitigation system of the present invention, the vacuum system module includes: a mechanical pump and a molecular pump; The mechanical pump is used to generate a low vacuum environment; The molecular pump is used to start in a low vacuum environment and cooperate with the mechanical pump to generate a high vacuum environment.

[0009] In the nuclear power material irradiation damage mitigation system of the present invention, the sample clamp module includes: a corundum sheet, a metal threaded column positive electrode, a metal threaded column negative electrode, a fastening nut, an electrode clamp, a fastening screw, and a thermocouple; The fastening screws and the electrode clips are used to clamp, fasten, and unload the sample to be treated; The fastening nut and the corundum plate are used to adjust the relative positions of the clamping platform. The thermocouple is used to detect the real-time temperature of the surface region of the sample to be processed. The positive electrode and the negative electrode of the metal threaded column are respectively connected to the pulse power module.

[0010] This invention also provides a method for assessing the mitigation of radiation damage to nuclear power materials, which uses the aforementioned nuclear power material radiation damage mitigation system for high-energy pulsed electric field mitigation treatment, and includes the following steps: Sample preparation and irradiation treatment to obtain a sample to be treated; the sample to be treated includes: non-irradiated sample and irradiated sample. The nanoindentation test and calculation were performed on the sample to be treated before the relief treatment to obtain the characteristic nanohardness data of the sample to be treated before the relief treatment. The sample to be treated was subjected to high-energy pulsed electric field mitigation treatment using a nuclear power material irradiation damage mitigation system. Nanoindentation test and calculation were performed on the sample after relief treatment to obtain the characteristic nanohardness value of the sample after relief treatment. The effect of high-energy pulsed electric field mitigation treatment on the sample to be treated is evaluated based on the characteristic nanohardness values ​​of the sample before and after mitigation treatment.

[0011] In the nuclear power material irradiation damage mitigation assessment method of the present invention, the step of evaluating the high-energy pulsed electric field mitigation effect of the sample to be treated based on the characteristic nanohardness values ​​of the sample before and after mitigation includes: Based on the characteristic nanohardness values ​​of the sample before and after the treatment, the relative hardening rate of the characteristic nanohardness of the sample under different conditions is calculated. Based on the relative hardening rate of the characteristic nanohardness of the samples under different conditions, the degree of mitigation of irradiation damage under high-energy pulsed electric field mitigation treatment was calculated. The effect of the high-energy pulsed electric field mitigation treatment on the sample to be treated is evaluated based on the mitigation degree parameter.

[0012] In the nuclear power material irradiation damage mitigation assessment method of the present invention, the mitigation degree parameter is calculated by the following formula: ; In the formula, The characteristic nanohardness value represents the surface characteristic region of sample X; The characteristic nanohardness value represents the matrix characteristic region of sample X. Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; The characteristic nanohardness value represents the surface characteristic region of sample Y; The characteristic nanohardness value represents the matrix characteristic region of sample Y. Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; where sample X is a non-irradiated sample, sample Y is an irradiated sample, and sample... Sample X is a sample that has undergone high-energy pulsed electric field mitigation treatment. The sample Y is a sample that has undergone high-energy pulsed electric field relief treatment.

[0013] In the nuclear power material irradiation damage mitigation assessment method of the present invention, the high-energy pulsed electric field mitigation treatment parameters meet the following requirements: The pulse current frequency is 10~200Hz; The pulse width of the pulse current is 10~1000 μs; The outdoor ambient temperature is: a maximum temperature of 800℃; The high-energy electrical pulse processing time is the total time between the start-up pulse current processing and the stop-down pulse current processing.

[0014] In the nuclear power material irradiation damage mitigation assessment method described in this invention, the nanoindentation test parameters meet the following requirements: The indenter is a Glass indenter; The number of test pressure points for each sample is greater than or equal to 9; The spacing between each pressure point is greater than or equal to 70 μm; The indentation depth at each indentation point is 2000 nm; The strain rate is 0.05 s. -1 .

[0015] The nuclear power material irradiation damage mitigation system and evaluation method of this invention have the following beneficial effects: The system includes: a sample clamp module to fix the sample to be treated; an external field heating module to provide a target space region for installation to the sample clamp module and to perform external field heating on the target space region; a vacuum system module to control the target space region in the external field heating module to enter a high vacuum environment; and a pulse power supply module to generate a pulse current to perform high-energy pulsed electric field mitigation treatment on the sample to be treated. This invention, through this irradiation damage mitigation system, can protect ion-irradiated damaged samples from surface oxidation under high-energy treatment conditions, and can also monitor temperature changes in real time during sample treatment. For small-sized samples, high-parameter electric pulse treatment experiments can be carried out, aiding in related irradiation damage mitigation research. Simultaneously, the quantitative evaluation of the irradiation damage mitigation effect provides technical methods and references for the life extension theory and engineering applications of nuclear power component materials. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings: Figure 1 This is a schematic diagram of the overall structure of the nuclear power material irradiation damage mitigation system provided by the present invention; Figure 2 This is a schematic diagram of the sample clamp module provided by the present invention; Figure 3 This is a flowchart illustrating the method for assessing radiation damage mitigation in nuclear power materials provided by the present invention. Figure 4 This is a schematic diagram of nano-hardness data processing before mitigation treatment provided by the present invention; Figure 5 This is a graph showing the representative curves and the ratio of the representative curves of sample X and sample Y after nanohardness testing provided by this invention. Figure 6 This is a graph showing the relationship between the square of the nanohardness and the reciprocal of the indentation depth for samples X and Y provided by this invention. Figure 7 This is a schematic diagram of linear fitting of characteristic segments of sample X and sample Y provided by the present invention; Figure 8 This is a schematic diagram of the sample clamping provided by the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] High-energy external field electric pulse treatment is a material treatment process that applies external electric / magnetic and thermal fields. Electropulsing treatment (EPT) involves applying a pulsed waveform current of a certain frequency and pulse width to the material, and it has certain application prospects in microstructure control and forming processes. The EPT process can alter the interaction between dislocations and pinning points, applying additional forces to the pinning points, breaking the interaction between dislocation lines and pinning points, and releasing them from the pinning state. On the other hand, the Joule heating generated by the pulsed current has an extremely high instantaneous temperature rise rate, and the energy input through the pulsed electric field can efficiently change the thermodynamic state of the material's microstructure, thereby controlling microstructural defects. The advantage of EPT treatment lies in its higher efficiency; it can be performed in real-time at temperatures lower than annealing mitigation temperatures, improving the safety of nuclear power component repair treatment. Based on this characteristic, this invention establishes a nuclear power material irradiation damage mitigation system, which is a material irradiation damage mitigation device system based on a high-energy pulsed electric field. This nuclear power material irradiation damage mitigation system is specifically designed to support experiments on mitigating ion irradiation damage samples. It establishes an experimental platform combining vacuum external heating and pulsed electric field treatment. This platform protects ion-irradiated damaged samples from surface oxidation under high-energy treatment conditions and allows for real-time monitoring of temperature changes during sample processing. For small-sized samples, it enables high-parameter EPT treatment experiments, aiding in related irradiation damage mitigation research. Furthermore, this invention evaluates the mitigation effect of ion irradiation damage on nuclear power materials based on a high-energy pulsed electric field material irradiation damage mitigation device. It designs a method for evaluating the mitigation effect of EPT treatment based on changes in nano-hardness after irradiation. This evaluation method can quantitatively calculate the degree of mitigation of ion irradiation damage after irradiation and electric pulse treatment, and reasonably guide the optimization of the EPT mitigation process. Overall, it provides technical methods and references for the theory and engineering application of life extension for nuclear power component materials.

[0019] The nuclear power material irradiation damage mitigation system provided by this invention is a device for mitigating / repairing irradiation damage to ion-irradiated metallic material samples. It can heat the sample under a certain vacuum environment via external field heating, and simultaneously perform pulsed current treatment within a certain temperature range, i.e., applying a pulsed current with a specific waveform signal to the sample. The nuclear power material irradiation damage mitigation system constructed according to this invention will be described below.

[0020] Specifically, such as Figure 1 As shown, the nuclear power material irradiation damage mitigation system comprises four main parts: a sample clamp module 40, an external heating module 20, a vacuum system module 30, and a pulse power supply module 10. It should be noted that... Figure 1This invention only describes the equipment combination design scheme of the nuclear power material irradiation damage mitigation system provided by the present invention, and the specific connection between the various devices is not specifically limited by the present invention.

[0021] In this embodiment of the invention, the pulse power supply module 10 is used to generate pulse current for high-energy pulsed electric field mitigation treatment of the sample to be treated. Specifically, the pulse power supply module 10 can regulate the output current state by setting pulse parameters to output a DC pulse current with corresponding waveform parameters, which is then applied to the sample. Preferably, the pulse power supply module 10 includes: an industrial-grade pulse power supply, a positive cable, and a negative cable; the industrial-grade pulse power supply regulates the output current state according to the set pulse parameters to generate pulse current; the positive cable is connected to the sample clamp module 40 and connected to the sample to be treated. The industrial-grade pulse power supply outputs pulse current through the positive and negative cable. The positive and negative cable conductors are required to withstand a maximum average current value ≤1000 A.

[0022] The pulse parameters of the industrial-grade pulse power supply are as follows: peak current intensity I ranges from 0 to 15000 A, frequency f ranges from 10 to 200 Hz, and pulse width W ranges from 10 to 1000 μs. By setting parameters I, f, and W to regulate the output pulse current, the average current intensity actually output to the cable conductor can be calculated based on the set parameters. The specific calculation expression is as follows: .

[0023] The external heating module 20 provides a target space area for the sample clamp module 40 to be installed and performs external heating on the target space area. The external heating module 20 includes a tubular flash furnace 21 and an industrial chiller 22. The tubular flash furnace 21 is equipped with a vacuum tube interface 23 and a lifting base device 24. The vacuum tube interface 23 is connected to the vacuum system module 30, and the lifting base device 24 is used to install the sample clamp module 40. The industrial chiller 22 is connected to the lifting base device 24 via a circulating water cooling pipe and is used to provide circulating cooling water to cool the tubular flash furnace 21.

[0024] Specifically, in this embodiment of the invention, the external heating module 20 consists of a tubular flash furnace 21 and an industrial chiller 22. This external heating module 20 is mainly used for external heating to create a certain range of high-temperature environment within the target space area. The tubular flash furnace 21 serves as the main body, with a quartz tube body and a diameter of 12cm. The upper section of the quartz tube is sealed with a flange, and the outer side of the middle section of the quartz tube is a covered asbestos insulation box. A high-temperature environment is generated inside the insulation box through resistance wire heating. A vacuum tube interface 23 is designed at the lower end of the quartz tube, connecting the internal space of the quartz tube to the vacuum system module 30, allowing the vacuum system module 30 to create a certain vacuum environment inside the quartz tube during operation. The tubular flash furnace 21 is also designed with a lifting base device 24. The sample clamp module 40 is installed on the lifting base device 24, and the relevant interfaces are sealed and insulated. The circulating water cooling pipe of the industrial chiller 22 is connected to the outer extension of the lifting base device 24. The circulating cooling water of the circulating water cooling pipe cools the sealing device at the bottom of the tubular flash furnace 21, preventing the rubber gasket material in the sealing area from being damaged due to heat aging.

[0025] In this embodiment of the invention, the tubular flash furnace 21 can be configured with a heating curve to achieve heat treatment processes such as heating, holding, and furnace cooling. The maximum temperature rise of the tubular flash furnace 21 needs to reach 800°C.

[0026] In this embodiment of the invention, the vacuum system module 30 is used to control the target space region in the external heating module 20 to enter a high vacuum environment. Preferably, the vacuum system module 30 includes: a mechanical pump and a molecular pump; the mechanical pump is used to generate a low vacuum environment; the molecular pump is used to start in the low vacuum environment and cooperate with the mechanical pump to generate a high vacuum environment.

[0027] Specifically, the vacuum system module 30 is mainly used to create a vacuum environment inside the quartz tube (i.e., the target space region) in the external field heating module 20, preventing the sample from oxidizing during heating. The vacuum system module 30 mainly consists of a mechanical pump and a molecular pump to form a vacuum pump unit. The mechanical pump is used to generate a low vacuum environment (reaching a vacuum level below 10 Pa); under this low vacuum environment, the molecular pump is then activated to generate a high vacuum environment (achieving an optimal vacuum level better than 5 × 10 Pa). -4 (Pa). Preferably, in this embodiment of the invention, the vacuum system module 30 needs to achieve the following vacuum level technical requirements: within 60 minutes of starting operation, the vacuum system module 30 is required to generate an environmental vacuum level of [missing information] in the target space area at room temperature. ≤5×10 -4 Pa.

[0028] In this embodiment of the invention, the sample clamp module 40 is used to fix the sample to be treated. Preferably, the sample clamp module 40 includes: an alumina sheet, a metal threaded column positive electrode 43, a metal threaded column negative electrode 44, a fastening nut, an electrode clamp 46, a fastening screw 45, and a thermocouple 47. The fastening screw 45 and the electrode clamp 46 are used to clamp, fasten, and unload the sample to be treated; the fastening nut and the alumina sheet are used to adjust the relative position of the clamp platform; the thermocouple 47 is used to detect the real-time temperature of the surface area of ​​the sample to be treated; the metal threaded column positive electrode 43 and the metal threaded column negative electrode 44 are respectively connected to the pulse power supply module 10.

[0029] Specifically, such as Figure 2 As shown, the sample clamp module 40 consists of alumina sheets (including upper and lower alumina sheets 41 and 42, respectively, made of alumina), metal threaded column electrodes (including a positive metal threaded column electrode 43 and a negative metal threaded column electrode 44, made of brass), a fastening nut (made of brass), an electrode clip 46 (made of brass), a fastening screw 45 (made of brass), and a thermocouple 47 (K-type thermocouple 47). In the sample clamp module 40, the sample is clamped, secured, and unloaded by adjusting the fastening screw 45 and the electrode clip 46; the relative position of the clamp platform is adjusted by adjusting the position of the fastening nut and the alumina sheet on the same side to accommodate samples of different sizes; and the contact position of the thermocouple 47 is adjusted to detect real-time temperature changes on the sample surface. The sample clamp module 40 of the present invention is a component structure specifically designed for the relief system of the present invention. The sheet sample is assembled in the sample clamp module 40 and forms a current loop with the pulse power supply module 10. The pulse current flows in from one electrode, passes through the sample and flows out from the other electrode. That is, the sample can be treated with pulse current through this design.

[0030] The nuclear power material irradiation damage mitigation system based on this invention is used to perform EPT (Enhanced Particulate Explosion) mitigation treatment on samples after ion irradiation. The nuclear power material irradiation damage mitigation assessment method provided by this invention performs nanoindentation tests before and after EPT treatment, calculates the relative hardening rate of the irradiated damage layer based on the hardness information of different characteristic segments of the nanoindentation, and establishes a method for calculating the degree of recovery of the difference in relative hardening rate before and after EPT treatment. Figure 3 The corresponding process is shown.

[0031] Specifically, such as Figure 3 As shown, the method for assessing radiation damage mitigation in nuclear power materials includes the following steps: Step S301: Sample preparation and irradiation treatment to obtain the sample to be treated; the sample to be treated includes: non-irradiated sample and irradiated sample.

[0032] In this embodiment of the invention, the sample to be treated is a square-shaped sample, and the sample material is generally the steel type used in nuclear power plants. In practical applications, at least two samples are included to be treated, one as a non-irradiated sample and the other as an irradiated sample. The two samples to be treated are identical parallel samples with the same dimensions. The sample length is a, the width is b, and the thickness is h, where 8 mm ≤ a ≤ 15 mm, 8 mm ≤ b ≤ 15 mm, and 0.5 mm ≤ h ≤ 2 mm.

[0033] The a×b surface on one side of the sample is polished to achieve a mirror finish. For ease of explanation, the method is described using two samples, designated X and Y, where sample X is a non-irradiated sample and sample Y is an irradiated sample subjected to ion irradiation treatment under certain conditions.

[0034] It should be noted that ion irradiation treatment refers to the process of generating an ion beam with a certain energy (the ion beam energy requirement is ≥200 keV) through an accelerator and irradiating the sample surface with the ion beam at the accelerator experimental terminal. The ion irradiation treatment described in this invention does not limit other ion irradiation conditions, such as specific types of ions, irradiation damage degree (dpa), irradiation temperature adjustment, etc. Furthermore, since the ion irradiation damage depth is relatively shallow, the irradiation damage area is generally located on the "surface" of the sample.

[0035] Step S302: Perform nanoindentation test and calculation on the sample to be treated before relief treatment to obtain the characteristic nanohardness data of the sample to be treated before relief treatment.

[0036] The nanoindentation test parameters meet the following requirements: the indenter is a Glass indenter; the number of test indentations per sample is greater than or equal to 9; the spacing between each indentation is greater than or equal to 70 μm; the indentation depth of each indentation is 2000 nm; and the strain rate is 0.05 s⁻¹. -1 .

[0037] Specifically, nanoindentation equipment was used to conduct continuous stiffness measurement (CSM) tests on the specimens (Specimen X and Specimen Y) before mitigation treatment. The nanoindentation test parameters were set as follows: the indenter was a Berkovich indenter, the number of test indentations per specimen was ≥9, the spacing between each indentation was ≥70 μm, the indentation depth of each indentation was 2000 nm, and the strain rate was 0.05 s⁻¹. -1 Poisson's ratio is chosen as the value of the sample material.

[0038] It should be noted that the relationship between the nanohardness H (in GPa) at each test indentation point and the indentation depth d (in nm) obtained from CSM mode testing generally exhibits an indentation size effect, where H decreases as d increases, in the curves obtained from CSM mode testing of metallic material samples. This is explained as follows: Figure 4 The figure shows the nanohardness curves of 10 indentation points. By averaging multiple curves, a representative curve representing the sample is obtained. The indentation depth range of the representative curve is retained from 80 nm to 2000 nm.

[0039] Nanoindentation tests were performed on samples X and Y, and the corresponding representative curves were obtained by processing, such as... Figure 5 As shown on the left, the representative curve of the irradiated sample Y is plotted as a ratio curve to the representative curve of the non-irradiated sample X, i.e., a curve is plotted. The relationship between indentation depth d (unit: nm) and indentation depth d is shown in the figure. Figure 5 As shown on the right, from Find the "ratio peak corresponding to the indentation depth" in the graph of the relationship between sample and indentation depth d (unit: nm). The value of “(unit: nm)”.

[0040] based on Figure 5 (Left) Relationship between nanohardness H (unit: GPa) and indentation depth d (unit: nm) of samples X and Y, respectively. Plot the square of the nanohardness of samples X and Y. (unit: ) and the reciprocal of the indentation depth 1000 / d (unit: A diagram showing the relationships between ) such as Figure 6 As shown.

[0041] Piecewise linear fitting was performed on the squares of the nanohardness and the reciprocals of the indentation depth data of samples X and Y, respectively, as follows: Figure 7 As shown, the arithmetic square root of the ordinate obtained by linear fitting is calculated to obtain the characteristic nanohardness values ​​(unit: GPa) of different segments.

[0042] The specific corresponding fitting segment is as follows: Sample surface characteristic sections: fitting Section, of which =1000 / ( +50), =1000 / ( -50), of which and Units are The characteristic nanohardness values ​​of the characteristic regions on the sample surface, calculated after fitting, are as follows: (Unit: GPa).

[0043] Specimen matrix characteristic regions: Fitting Section, of which =0.5 , =1.0 The characteristic nanohardness values ​​of the characteristic segments of the sample matrix after fitting are as follows: (Unit: GPa).

[0044] Based on the above fitting, the characteristic nanohardness values ​​of samples X and Y before the mitigation treatment were obtained: Characteristic nanohardness values ​​of the surface feature section of sample X: (Unit: GPa); Characteristic nanohardness values ​​of the matrix characteristic region of sample X: (Unit: GPa); Characteristic nanohardness values ​​of the surface characteristic section of sample Y: (Unit: GPa); Characteristic nanohardness values ​​of the matrix characteristic region of sample Y: (Unit: GPa).

[0045] Step S303: The sample to be treated is subjected to high-energy pulsed electric field mitigation treatment using a nuclear power material irradiation damage mitigation system.

[0046] The high-energy pulse electric field mitigation parameters meet the following requirements: pulse current frequency: 10~200Hz; pulse current pulse width: 10~1000 μs; ambient temperature: up to 800℃; high-energy pulse processing time: the total time between turning on the pulse current processing and turning off the pulse current.

[0047] Specifically, high-energy pulsed electric field mitigation treatment with the same parameters was applied to samples X and Y respectively. The samples were assembled into the nuclear power material irradiation damage mitigation system provided by this invention (hereinafter referred to as the "mitigation device" for ease of explanation), and the samples were fixed by the sample clamp module 40, as shown below. Figure 8 As shown. It should be noted that, for the square sample undergoing mitigation treatment in this invention, such as... Figure 8 As shown, when clamping, it is necessary to ensure that the sample is clamped symmetrically from top to bottom, and the clamping length c at the upper / lower end must satisfy: 1mm ≤ c≤ a / 3 (mm).

[0048] After the sample is fixed in the fixture of the "relief device", the fixture module is installed into the quartz tube of the external field heating module 20, and the external field heating module 20 is sealed and tightened. The vacuum system module 30 is then turned on until the generated ambient vacuum level P is reached. v ≤5×10 -4Pa, the high-energy pulsed electric field mitigation treatment was initiated on the sample. It should be noted that the parameters for the high-energy pulsed electric field mitigation treatment are as follows: Pulse current frequency f (unit: Hz): 10~200Hz; In specific applications, it can be selected according to the specific parameter settings of the pulse power supply module 10. The pulse width W of the pulse current is 10~1000μs; in specific applications, it can be selected according to the specific parameter settings of the pulse power supply module 10. The ambient temperature T is: the maximum temperature reaches 800℃; in specific applications, it can be determined based on the maximum temperature rise of the tubular flash furnace 21 in the outdoor heating module 20. Processing current density J (unit: The average current intensity is obtained by setting and calculating the pulse power module 10 device. (Unit: A) and the cross-sectional dimensions of the specimen are calculated using the following formula: High-energy electrical pulse processing time t (unit: min): The total time between the start of pulse current processing and the stop of pulse current processing.

[0049] Step S304: Perform nanoindentation test and calculation on the sample after relief treatment to obtain the characteristic nanohardness value of the sample after relief treatment.

[0050] After the mitigation treatment in step S303, the mitigated state samples X and Y are obtained, and are defined as samples respectively. and sample The sample was treated using the same method as in step S302. and sample Nanoindentation tests were performed, and the results of the relief treatment on the sample were calculated. and sample The characteristic nanohardness values ​​are as follows: Sample Characteristic nanohardness values ​​of surface feature sections: (Unit: GPa); Sample Characteristic nanohardness values ​​of the matrix feature segments: (Unit: GPa); Sample Characteristic nanohardness values ​​of surface feature sections: (Unit: GPa); Sample Characteristic nanohardness values ​​of the matrix feature segments: (Unit: GPa); It should be noted that, in the process of selecting the "surface characteristic section" of the sample after mitigation treatment, the ratio peak corresponds to the indentation depth d. p The value (unit: nm) is consistent with that in step S302 and does not need to be recalculated.

[0051] Step S305: Evaluate the effect of high-energy pulsed electric field mitigation treatment on the sample to be treated based on the characteristic nano-hardness values ​​of the sample before and after mitigation treatment.

[0052] The evaluation of the high-energy pulsed electric field mitigation effect on the samples to be treated, based on the characteristic nanohardness values ​​of the samples before and after mitigation, includes: calculating the relative hardening rate of the characteristic nanohardness of the samples under different conditions based on the characteristic nanohardness values ​​of the samples before and after mitigation; calculating the mitigation degree parameter of irradiation damage under high-energy pulsed electric field mitigation based on the relative hardening rate of the characteristic nanohardness of the samples under different conditions; and evaluating the mitigation effect of high-energy pulsed electric field mitigation on the samples to be treated based on the mitigation degree parameter.

[0053] The characteristic nanohardness values ​​of the corresponding samples after mitigation treatment are calculated. Combined with the characteristic nanohardness values ​​of the corresponding samples before mitigation treatment calculated in step S302, and based on the relative hardening rates of the characteristic nanohardness of samples under different conditions, the mitigation degree parameter of irradiation damage under high-energy pulsed electric field mitigation treatment is calculated. Among them, the mitigation degree parameter ( The formula for calculating ) is as follows: ; In the formula, The characteristic nanohardness value represents the surface characteristic region of sample X; The characteristic nanohardness value represents the matrix characteristic region of sample X. Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; The characteristic nanohardness value represents the surface characteristic region of sample Y; The characteristic nanohardness value represents the matrix characteristic region of sample Y. Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; where sample X is a non-irradiated sample, sample Y is an irradiated sample, and sample... Sample X is a sample that has undergone high-energy pulsed electric field mitigation treatment. The sample Y is a sample that has undergone high-energy pulsed electric field relief treatment.

[0054] Based on the calculation Values ​​are used to assess the effectiveness of mitigation treatments, i.e. The higher the value (R≥0), the better the relief effect of EPT treatment.

[0055] This invention establishes a material irradiation damage mitigation device system based on a high-energy pulsed electric field. Specifically designed to support experiments on mitigating ion irradiation damage, it constructs an experimental platform combining vacuum external heating and pulsed electric field treatment. This platform protects ion-irradiated damaged samples from surface oxidation under high-energy treatment conditions and allows for real-time monitoring of temperature changes during sample processing. For small-sized samples, it enables high-parameter EPT treatment experiments, aiding in related irradiation damage mitigation research. Furthermore, this invention evaluates the mitigation effect of the high-energy pulsed electric field-based material irradiation damage mitigation system on ion irradiation damage in nuclear power materials, designing a method for calculating the EPT treatment mitigation effect based on changes in nano-hardness after irradiation. This evaluation method can quantitatively calculate the degree of mitigation of ion irradiation damage after irradiation and pulsed electric field treatment, and reasonably guide the optimization of the EPT mitigation process. Overall, it provides technical methods and references for the theory and engineering application of life extension for nuclear power component materials.

[0056] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0057] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0058] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0059] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They do not limit the scope of protection of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the claims of the present invention.

Claims

1. A radiation damage mitigation system for nuclear power materials, characterized in that, include: A sample clamp module, which is used to fix the sample to be processed; An external heating module is used to provide a target space area for installation to the sample clamp module and to perform external heating on the target space area; A vacuum system module, which is used to control the target space region in the external heating module to enter a high vacuum environment; A pulse power supply module is used to generate pulse current to perform high-energy pulse electric field relief treatment on the sample to be treated.

2. The nuclear power material irradiation damage mitigation system according to claim 1, characterized in that, The pulse power module includes: an industrial-grade pulse power supply, a positive cable conductor, and a negative cable conductor; The industrial-grade pulse power supply generates the pulse current by adjusting the output current state according to the pulse parameters set. The positive cable wires are respectively connected to the sample clamp module and connected to the sample to be processed.

3. The nuclear power material irradiation damage mitigation system according to claim 1, characterized in that, The external heating module includes: a tubular flash furnace and an industrial chiller; The tubular flash furnace is equipped with a vacuum tube interface and a lifting base device; the vacuum tube interface is connected to the vacuum system module, and the lifting base device is used to install the sample clamp module. The industrial chiller is connected to the lifting base device via a circulating water cooling pipe, and is used to provide circulating cooling water through the circulating water cooling pipe to cool the tubular flash furnace.

4. The nuclear power material irradiation damage mitigation system according to claim 1, characterized in that, The vacuum system module includes: a mechanical pump and a molecular pump; The mechanical pump is used to generate a low vacuum environment; The molecular pump is used to start in a low vacuum environment and cooperate with the mechanical pump to generate a high vacuum environment.

5. The nuclear power material irradiation damage mitigation system according to any one of claims 1-4, characterized in that, The sample clamp module includes: a corundum sheet, a metal threaded positive electrode, a metal threaded negative electrode, a fastening nut, an electrode clamp, a fastening screw, and a thermocouple; The fastening screws and the electrode clips are used to clamp, fasten, and unload the sample to be treated; The fastening nut and the corundum plate are used to adjust the relative position of the clamping platform. The thermocouple is used to detect the real-time temperature of the surface region of the sample to be processed. The positive electrode and the negative electrode of the metal threaded column are respectively connected to the pulse power module.

6. A method for assessing the mitigation of radiation damage to nuclear power materials, comprising using the nuclear power material radiation damage mitigation system according to any one of claims 1-5 for high-energy pulsed electric field mitigation treatment, characterized in that, Includes the following steps: Sample preparation and irradiation treatment to obtain the sample to be treated; The samples to be treated include: non-irradiated samples and irradiated samples; The nanoindentation test and calculation were performed on the sample to be treated before the relief treatment to obtain the characteristic nanohardness data of the sample to be treated before the relief treatment. The sample to be treated was subjected to high-energy pulsed electric field mitigation treatment using a nuclear power material irradiation damage mitigation system. Nanoindentation test and calculation were performed on the sample after relief treatment to obtain the characteristic nanohardness value of the sample after relief treatment. The effect of high-energy pulsed electric field mitigation treatment on the sample to be treated is evaluated based on the characteristic nanohardness values ​​of the sample before and after mitigation treatment.

7. The method for assessing the mitigation of radiation damage to nuclear power materials according to claim 6, characterized in that, The evaluation of the high-energy pulsed electric field mitigation effect of the sample to be treated based on the characteristic nanohardness values ​​of the sample before and after mitigation includes: Based on the characteristic nanohardness values ​​of the sample before and after the relief treatment, the relative hardening rate of the characteristic nanohardness of the sample under different conditions is calculated. Based on the relative hardening rate of the characteristic nanohardness of the samples under different conditions, the degree of mitigation of irradiation damage under high-energy pulsed electric field mitigation treatment was calculated. The effect of the high-energy pulsed electric field mitigation treatment on the sample to be treated is evaluated based on the mitigation degree parameter.

8. The method for assessing the mitigation of radiation damage to nuclear power materials according to claim 7, characterized in that, The degree of relief parameter is obtained by calculating the following formula: ； In the formula, The characteristic nanohardness value represents the surface characteristic region of sample X; The characteristic nanohardness value represents the matrix characteristic region of sample X; Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; The characteristic nanohardness value represents the surface characteristic region of sample Y; The characteristic nanohardness value represents the matrix characteristic region of sample Y. Indicates the sample The characteristic nanohardness values ​​of the surface feature sections; Indicates the sample The characteristic nanohardness values ​​of the matrix characteristic segments; where sample X is a non-irradiated sample, sample Y is an irradiated sample, and sample... Sample X is a sample that has undergone high-energy pulsed electric field mitigation treatment. The sample Y is a sample that has undergone high-energy pulsed electric field relief treatment.

9. The method for assessing the mitigation of radiation damage to nuclear power materials according to any one of claims 6-8, characterized in that, The parameters for high-energy pulsed electric field mitigation processing must meet the following requirements: The pulse current frequency is 10~200Hz; The pulse width of the pulse current is 10~1000 μs; The outdoor ambient temperature is: a maximum temperature of 800℃; The high-energy electrical pulse processing time is the total time between the start-up pulse current processing and the stop-down pulse current processing.

10. The method for assessing the mitigation of radiation damage to nuclear power materials according to claim 9, characterized in that, The nanoindentation test parameters must meet the following requirements: The indenter is a Glass indenter; The number of test pressure points for each sample is greater than or equal to 9; The spacing between each pressure point is greater than or equal to 70 μm; The indentation depth at each indentation point is 2000 nm; The strain rate is 0.05 s. -1 .

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