Helium ion irradiation damage simulation and characterization method and device for concrete three-phase structure

Abstract

The invention discloses a concrete three-phase structure helium ion irradiation damage simulation and characterization method and device, and the method comprises the steps: building a concrete multi-phase component model, respectively simulating the irradiation damage behaviors of helium ions in each single phase, and carrying out the integration through a volume fraction weighted average method to obtain the irradiation damage distribution of the whole concrete. By adopting the technical scheme of the invention, the displacement damage, energy deposition and vacancy distribution key parameters of the concrete under helium ion irradiation can be quantitatively represented, and a theoretical basis and data support are provided for life evaluation and anti-irradiation design of a nuclear facility concrete structure.

Description

Technical Field

[0001] This invention belongs to the field of nuclear engineering material irradiation damage simulation technology, and particularly relates to a method and apparatus for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure. Background Technology

[0002] Concrete, due to its excellent mechanical properties, radiation shielding ability, and economy, has become an indispensable structural material in nuclear facilities such as nuclear power plant containment structures, biosafety walls, and reactor support structures. During reactor operation, concrete structures are exposed to strong radiation fields for extended periods, enduring irradiation from neutrons, gamma rays, and various charged particles. Among these, helium ions (alpha particles) act as neutrons and undergo transmutation reactions with elements such as boron and lithium (e.g., ...). 10 B(n,α) 7 The products of Li and the products of actinide α decay gradually accumulate in the shallow surface layer of concrete (typically 10–100 μm), causing significant material damage.

[0003] The accumulation of helium ions in concrete triggers a series of microstructural degradation behaviors, including vacancy clustering, helium bubble nucleation, lattice distortion, and swelling. These microscopic damages further lead to the deterioration of macroscopic properties, such as decreased strength, increased brittleness, and increased permeability, seriously threatening the long-term integrity and service safety of concrete structures.

[0004] Currently, the primary method for assessing concrete irradiation damage still relies on real-world irradiation experiments. However, these experiments are not only time-consuming and costly, but also carry significant radioactive risks, are difficult to perform, and struggle to achieve in-situ, real-time observation of damage evolution. Furthermore, irradiation experiments cannot cover all practical working conditions, such as different mix proportions, irradiation doses, and energy spectrum conditions, limiting their systematicity and applicability.

[0005] In simulation studies, SRIM (The Stopping and Range of Ions in Matter), an ion transport simulation software based on the Monte Carlo method, has been widely used in research on ion implantation, radiation damage, and semiconductor doping. This software can accurately simulate key parameters such as ion range, energy loss, and vacancy generation in materials, offering advantages such as high efficiency, strong parameterization capabilities, and intuitive results. However, SRIM software defaults to treating materials as homogeneous amorphous targets, making it unable to directly simulate multiphase, non-homogeneous composite materials like concrete with aggregate, mortar, and interfacial transition zones (ITZs). This significantly limits its application in nuclear concrete irradiation damage research. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method and apparatus for simulating and characterizing helium ion irradiation damage in three-phase concrete structures.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, comprising:

[0009] S1. Establish a three-phase component model of concrete, including aggregate phase, mortar matrix phase and interfacial transition zone (ITZ) phase;

[0010] S2. Set the chemical composition, density, and volume fraction of each phase respectively;

[0011] S3 simulates the transport process of helium ions in each phase and the damage response;

[0012] S4. Extract irradiation damage data for each phase, including ion range, vacancy distribution, energy deposition, and displacement damage (DPA).

[0013] S5. The damage data are weighted and averaged according to the volume fraction of each phase to obtain the overall irradiation damage distribution of the concrete.

[0014] Preferably, the aggregate phase is SiO2 with a density of 2.65 g / cm³. 3 The mortar matrix phase is CaO·SiO2·H2O, with a density of 2.10-2.21 g / cm³. 3 The ITZ phase has the same chemical composition as the mortar matrix, but its density is set to 1.68-1.90 g / cm³. 3 .

[0015] Preferably, the helium ion energy is 2 MeV, the incident angle is 0°, and the flux is 1 × 10⁻⁶. 16 ions / cm 2 .

[0016] Preferably, the weighted average formula is:

[0017]

[0018] Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i (z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively.

[0019] This invention also provides a device for simulating and characterizing helium ion irradiation damage in three-phase concrete structures, comprising:

[0020] The first processing module is used to establish a three-phase component model of concrete, including aggregate phase, mortar matrix phase and interfacial transition zone (ITZ) phase.

[0021] The second processing module is used to set the chemical composition, density, and volume fraction of each phase respectively;

[0022] The third processing module is used to simulate the transport process and damage response of helium ions in each phase, respectively.

[0023] The fourth processing module is used to extract irradiation damage data for each phase, including ion range, vacancy distribution, energy deposition, and displacement damage (DPA).

[0024] The fifth processing module is used to perform a weighted average of the damage data based on the volume fraction of each phase to obtain the overall irradiation damage distribution of the concrete.

[0025] Preferably, the aggregate phase is SiO2 with a density of 2.65 g / cm³. 3 The mortar matrix phase is CaO·SiO2·H2O, with a density of 2.10-2.21 g / cm³. 3 The ITZ phase has the same chemical composition as the mortar matrix, but its density is set to 1.68-1.90 g / cm³. 3 .

[0026] Preferably, the helium ion energy is 2 MeV, the incident angle is 0°, and the flux is 1 × 10⁻⁶. 16 ions / cm 2 .

[0027] Preferably, the weighted average formula is:

[0028]

[0029] Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i (z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively.

[0030] This invention overcomes the limitation of SRIM in directly simulating non-homogeneous materials by employing a strategy of phase-separate modeling, separate simulation, and weighted integration, thus achieving cross-scale quantitative characterization of concrete irradiation damage. This invention is not limited to helium ion irradiation simulation; by adjusting the incident ion type, energy, and target parameters in the SRIM software, it can also be applied to the study of damage behavior in concrete by protons, heavy ions, and other high-energy charged particles, or other gaseous ions generated by neutron transmutation. Furthermore, the established multiphase modeling and weighted average integration strategy has good universality and can be further extended to the simulation and durability assessment of ion irradiation damage in other multiphase non-homogeneous composite systems such as asphalt concrete and radiation-shielded composite materials. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Figure 1 This is a flowchart of the method for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure according to an embodiment of the present invention;

[0033] Figure 2 The images show the trajectory of 10,000 incident helium ions at an energy of 2 MeV, vertically irradiated into different phases. (a) represents the aggregate layer; (b) represents the mortar layer; and (c) represents the ITZ layer (interface transition zone).

[0034] Figure 3 A comparison of the changes in the total stopping power of each microphase of concrete and the overall concrete as a whole with the depth of incidence. Detailed Implementation

[0035] 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.

[0036] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0037] Example 1:

[0038] This invention provides a method for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, comprising:

[0039] S1. Construction and parameterization of the multiphase structure model of concrete: The main constituent phases of concrete are identified, including the aggregate phase, mortar matrix phase, and interfacial transition zone (ITZ) phase. Based on the actual physicochemical properties of each phase, its representative chemical composition, mass density, and volume fraction in concrete are determined. The aggregate phase is represented by silica (SiO2), with a density set to 2.65 g / cm³. 3The volume fraction is 55%–60%; the mortar matrix phase is represented by hydrated calcium silicate (CaO·SiO2·H2O), and the target material composition is configured according to its elemental weight ratio, with a density set at 2.10–2.21 g / cm³. 3 The volume fraction is 35%–40%; the interfacial transition zone (ITZ) phase has the same chemical composition as the mortar matrix phase, but with a lower density value of 1.68–1.90 g / cm³. 3 To characterize its high porosity, the volume fraction is 5%–10%;

[0040] S2. Unified Setting of SRIM Simulation Parameters and Phase Separation Simulation: Based on the typical energy of helium ions produced by nuclear reaction transmutation, unified simulation parameters are set in the TRIM module of the SRIM software; the incident ion is a helium ion carrying two positive charges (He). 2+ The energy was set to 2 MeV, the incident angle to 0° to simulate an isotropic irradiation field, the total number of incident ions to 10,000 to ensure statistical significance, and the target thickness to 15 μm (greater than the maximum projected range of 2 MeV helium ions). Three independent homogeneous targets were constructed with the composition and density of the aggregate phase, mortar phase, and ITZ phase defined in S1, respectively. The "Full Damage Cascades" full-cascade damage mode was enabled for simulation, and the displacement threshold energy (Ed) of each element was set to the default recommended value of SRIM software. The simulation flux was set to 1 × 10⁻⁶ based on the equivalent long-term service dose of nuclear power plant concrete. 16 ions / cm 2 ;

[0041] S3. Extraction of irradiation damage data for each phase: After running the SRIM simulation, extract the distribution data of key irradiation damage parameters with depth from the simulation results of each phase; the key parameters include: the range distribution of incident ions, the number and depth distribution of vacancies, the energy deposition distribution (including electron stopping power and nuclear stopping power), and the raw data used to calculate displacement damage (DPA).

[0042] S4. Macroscopic damage characterization based on volume fraction weighted average: Based on the volume fraction of each phase set in S1, the depth distribution data of each phase damage parameter obtained in S3 are calculated by weighted average to synthesize the overall irradiation damage distribution of macroscopic concrete; for displacement damage (DPA), the weighted average calculation formula is as follows:

[0043]

[0044] Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i(z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively; a similar weighted average method is simultaneously applied to characterize the ion concentration distribution, vacancy distribution, and energy deposition distribution.

[0045] S5. Results Analysis and Verification: Analyze the overall damage distribution curve of concrete obtained after weighted averaging, determine key damage characteristic parameters, including damage peak value, peak depth, and damage distribution width; compare the calculated average projected range and damage peak depth with theoretical predictions to verify the reliability of the simulation results; finally, output quantitative charts and data that can be used to assess the degree of concrete irradiation damage.

[0046] Furthermore, the simulated flux Φ mentioned in step S2 is determined by equivalently distributing the concentration of helium atoms generated by the transmutation reaction of the cumulative fast neutron flux (E>1MeV) in the concrete during reactor operation at the characteristic damage depth, according to the formula Φ_He=Helium Concentration×Damage Depth.

[0047] This invention's method is not limited to helium ion irradiation simulation. By adjusting the incident ion type, energy, and target parameters in the SRIM software, it can also be applied to the study of damage behavior of other high-energy charged particles such as protons and heavy ions, or other gaseous ions generated by neutron transmutation, in concrete. Furthermore, the established multiphase modeling and weighted average integration strategy has good universality and can be further extended to the simulation and durability assessment of ion irradiation damage in other multiphase non-homogeneous composite systems such as asphalt concrete and radiation-shielded composite materials.

[0048] Example 2:

[0049] like Figure 1 As shown, this embodiment of the invention provides a method for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, comprising:

[0050] S1, Construction of a three-phase concrete model;

[0051] a) Aggregate phase modeling: Silica (SiO2) was used as a simplified representative of the aggregate phase, with its density set to 2.65 g / cm³. 3 The atomic percentage composition is O: 66.67%, Si: 33.33%, and it is given a volume fraction of 55% in the overall concrete model;

[0052] b) Mortar matrix phase modeling: Calcium silicate hydrate (CaO·SiO2·H2O) was used as the representative of the mortar matrix phase. The target material composition was configured according to the elemental weight ratio Ca:Si:O:H = 40:28:15:1, and the density was set to 2.10 g / cm³.3 The volume fraction is 40%.

[0053] c) ITZ phase modeling: The interface transition zone uses the same chemical composition as the mortar matrix phase. To accurately characterize its porous and loose structural features, its density is set to 1.68 g / cm³. 3 The volume fraction is 5%.

[0054] S2. Set uniform simulation parameters in the SRIM software. Select helium ions with two positive charges as the incident ion type. 2+ The energy was set to 2 MeV, and the simulated flux was 1 × 10⁻⁶. 16 ions / cm 2 A vertical incidence method was adopted, with the incidence angle set to 0°. The total number of incident ions in each simulation was set to 10,000 to ensure the reliability of the statistical results. The thickness of all target materials was uniformly set to 15 μm, which is greater than the maximum projected range of 2 MeV helium ions, ensuring that the ion energy is completely deposited within the target material. The displacement threshold energy (Ed) of each element in the target material was directly adopted from the recommended default values ​​built into the SRIM software.

[0055] S3. Perform independent simulation calculations for the three phases—aggregate, mortar, and ITZ—in the SRIM / TRIM module. For example... Figure 2 Figures (a), (b), and (c) show the trajectory diagrams of helium ions in the aggregate phase, mortar phase, and ITZ phase, respectively, visually reflecting the differences in helium ion transport behavior and damage distribution in different phases. S4. The damage data of the three phases are integrated using the volume fraction weighted average method. Based on the preset volume fraction (aggregate:mortar:ITZ = 55%:40%:5%), the formula is used...

[0056] DPA concrete (z)=DPA agg (z)·0.55+DPA mortar (z)·0.4+DPA itz (z)·0.05

[0057] The depth distribution of displacement damage (DPA) in macroscopic concrete was calculated. The vacancy distribution and energy deposition distribution were then weighted in the same way to synthesize the overall irradiation damage distribution curve of the concrete.

[0058] Furthermore, the energy deposition behavior of each phase and the overall concrete was analyzed, such as... Figure 3 As shown, the changes in the total stopping power of each microphase and the overall concrete with the incident depth were compared. It can be seen that electron stopping power dominates the total stopping power (>95%), and there are obvious differences in the distribution of stopping power of each phase.

[0059] S5. Results Analysis: The damage peak was located at a depth of 7.65 μm, which coincides with the average projected range of helium ions; the aggregate phase damage was the shallowest and most concentrated, while the ITZ phase damage was the deepest and most dispersed; (e.g., ...) Figure 3 As shown, electron blocking capacity accounts for more than 95% of the total blocking capacity, and the total blocking capacity of each phase and the overall concrete varies significantly with depth.

[0060] This invention is the first to apply the multiphase weighted average method to the simulation of concrete irradiation damage. By employing a strategy of phase-separated modeling, separate simulation, and weighted integration, it effectively overcomes the limitation of SRIM software in directly simulating non-homogeneous materials. It achieves cross-scale prediction from microscopic mechanisms to macroscopic responses, providing a reliable, efficient, and low-cost simulation method for life assessment of nuclear concrete, research on irradiation damage mechanisms, and design of radiation-resistant materials.

[0061] Example 3:

[0062] This invention also provides a device for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, comprising:

[0063] The first processing module is used to establish a three-phase component model of concrete, including aggregate phase, mortar matrix phase and interfacial transition zone (ITZ) phase.

[0064] The second processing module is used to set the chemical composition, density, and volume fraction of each phase respectively;

[0065] The third processing module is used to simulate the transport process and damage response of helium ions in each phase, respectively.

[0066] The fourth processing module is used to extract irradiation damage data for each phase, including ion range, vacancy distribution, energy deposition, and displacement damage (DPA).

[0067] The fifth processing module is used to perform a weighted average of the damage data based on the volume fraction of each phase to obtain the overall irradiation damage distribution of the concrete.

[0068] In one embodiment of the present invention, the aggregate phase is SiO2 with a density of 2.65 g / cm³. 3 The mortar matrix phase is CaO·SiO2·H2O, with a density of 2.10-2.21 g / cm³. 3 The ITZ phase has the same chemical composition as the mortar matrix, but its density is set to 1.68-1.90 g / cm³. 3 .

[0069] As one embodiment of the present invention, the helium ion energy is 2 MeV, the incident angle is 0°, and the flux is 1 × 10⁻⁶. 16 ions / cm 2 .

[0070] As one embodiment of the present invention, the weighted average formula is:

[0071]

[0072] Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i (z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively.

[0073] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, characterized in that, include: S1. Establish a three-phase component model of concrete, including aggregate phase, mortar matrix phase and interfacial transition zone (ITZ) phase; S2. Set the chemical composition, density, and volume fraction of each phase respectively; S3 simulates the transport process of helium ions in each phase and the damage response; S4. Extract irradiation damage data for each phase, including ion range, vacancy distribution, energy deposition, and displacement damage (DPA). S5. The damage data are weighted and averaged according to the volume fraction of each phase to obtain the overall irradiation damage distribution of the concrete.

2. The method for simulating and characterizing helium ion irradiation damage in three-phase concrete structures as described in claim 1, characterized in that, The aggregate phase is SiO2, with a density of 2.65 g / cm³. 3 The mortar matrix phase is CaO·SiO2·H2O, with a density of 2.10-2.21 g / cm³. 3 The ITZ phase has the same chemical composition as the mortar matrix, but its density is set to 1.68-1.90 g / cm³. 3 .

3. The method for simulating and characterizing helium ion irradiation damage in three-phase concrete structures as described in claim 2, characterized in that, The helium ion energy is 2 MeV, the incident angle is 0°, and the flux is 1 × 10⁻⁶. 16 ions / cm 2 .

4. The method for simulating and characterizing helium ion irradiation damage in three-phase concrete structures as described in claim 2, characterized in that, The weighted average formula is as follows: Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i (z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively.

5. A device for simulating and characterizing helium ion irradiation damage in a three-phase concrete structure, characterized in that, include: The first processing module is used to establish a three-phase component model of concrete, including aggregate phase, mortar matrix phase and interfacial transition zone (ITZ) phase. The second processing module is used to set the chemical composition, density, and volume fraction of each phase respectively; The third processing module is used to simulate the transport process and damage response of helium ions in each phase, respectively. The fourth processing module is used to extract irradiation damage data for each phase, including ion range, vacancy distribution, energy deposition, and displacement damage (DPA). The fifth processing module is used to perform a weighted average of the damage data based on the volume fraction of each phase to obtain the overall irradiation damage distribution of the concrete.

6. The apparatus for simulating and characterizing helium ion irradiation damage of three-phase concrete structures as described in claim 5, characterized in that, The aggregate phase is SiO2, with a density of 2.65 g / cm³. 3 The mortar matrix phase is CaO·SiO2·H2O, with a density of 2.10-2.21 g / cm³. 3 The ITZ phase has the same chemical composition as the mortar matrix, but its density is set to 1.68-1.90 g / cm³. 3 .

7. The apparatus for simulating and characterizing helium ion irradiation damage of three-phase concrete structures as described in claim 6, characterized in that, The helium ion energy is 2 MeV, the incident angle is 0°, and the flux is 1 × 10⁻⁶. 16 ions / cm 2 .

8. The apparatus for simulating and characterizing helium ion irradiation damage of three-phase concrete structures as described in claim 7, characterized in that, The weighted average formula is as follows: Among them, DPA concrete (z) represents the overall displacement damage value of the concrete at depth z, DPA i (z) represents the displacement damage value of the i-th phase at depth z, v i Let be the volume fraction of the i-th phase, where i represents the aggregate, mortar, and ITZ phase, respectively.

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