Calibration method for series boron-aluminum standard samples

Abstract

The invention discloses a method for calibrating a series of boron-aluminum standard samples. The method comprises the following steps: testing the boron-aluminum standard samples to obtain a first total boron content and a first 10B abundance; obtaining a first 10B surface density of the boron-aluminum standard sample based on the first total boron content and the first 10B abundance; determining a second 10B surface density of the boron-aluminum standard sample according to the pure B4C samples with different 10B surface densities; and fitting the first 10B surface density and the second 10B surface density, and calibrating the 10B surface density of the boron-aluminum standard sample. According to the method, two different independent paths of a chemical method and a hot-pressing pure B4C standard sample comparison method are adopted to obtain the 10B surface density of a series of boron-aluminum standard samples, first-order linear fitting mutual verification is carried out, the 10B surface density of the series of boron-aluminum standard samples is finally calibrated, and the reliability and accuracy of neutron absorption performance detection of the engineering boron-aluminum plate are ensured.

Description

Technical Field

[0001] This application relates to the field of neutron absorption performance testing technology for neutron-absorbing materials in nuclear power projects, specifically to a calibration method for a series of boron-aluminum standard samples. Background Technology

[0002] Currently, there are no unified test methods and standards for neutron-absorbing materials used to ensure critical safety, nor are there traceable metrological standards for calibrating equipment. This makes it difficult to make standardized judgments on the neutron absorption performance of these materials. 10 The detection of B content and uniformity has great uncertainty, posing significant engineering risks in terms of critical safety.

[0003] Therefore, there is an urgent need to conduct research on metrological standards for neutron absorption performance testing. The instruments and equipment used in neutron absorption performance testing should possess good stability and accuracy, and need to be calibrated using a series of standard samples to ensure that the testing conditions meet the requirements. Currently, there are no standard samples for neutron absorption testing, and with the decay of the neutron source, it is difficult to guarantee the reliability and accuracy of the test.

[0004] Existing technology CN113866046B discloses a method for measuring the surface density of thermal neutron-absorbing materials. By measuring the thermal neutron transmittance of a set of standard thermal neutron-absorbing material samples with known surface densities, a functional relationship between the transmittance and surface density of the thermal neutron-absorbing material is established. This relationship is then used to calculate the surface density of unknown samples, thus constructing a method for rapidly and accurately measuring the surface density of thermal neutron-absorbing nuclides without destroying the physical structure of the sample. However, this method cannot obtain an accurate and traceable series of boron-aluminum standard samples. 10 B-plane density makes it difficult to make a unified and standardized judgment on the neutron absorption performance of materials.

[0005] Existing technology CN107561104B discloses a device for detecting the neutron absorption performance of boron-aluminum alloy materials in nuclear power plants. The device includes a transmission mechanism mounted on a detection platform. A boron-aluminum plate moves horizontally along the platform under the drive of the transmission mechanism. Above the platform are several detectors arranged sequentially along the direction of movement of the boron-aluminum plate. The detectors are connected to a data acquisition system, which is connected to a control terminal. A neutron source is positioned below the plane of movement of the boron-aluminum plate, and the neutron source is housed within a moderation shielding device. This method cannot obtain an accurate and traceable series of boron-aluminum standard samples. 10 B-plane density makes it difficult to make a unified and standardized judgment on the neutron absorption performance of materials.

[0006] In summary, neither of the two existing technologies can obtain an accurate and traceable series of boron-aluminum standard samples. 10B-plane density makes it difficult to make a unified and standardized judgment on the neutron absorption performance of materials. Summary of the Invention

[0007] The purpose of this application is to solve the aforementioned technical problems.

[0008] To achieve the above objectives, this application proposes a series of boron-aluminum standard sample calibration methods, including: The first total boron content and the first... were obtained by testing the boron-aluminum standard sample. 10 B abundance; Based on the first total boron content and the first 10 The abundance of B was obtained from the first boron-aluminum standard sample. 10 B-side density; According to different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 B-side density; For the first 10 B-surface density and second 10 The density of surface B is fitted to calibrate the boron-aluminum standard sample. 10 B-surface density.

[0009] Furthermore, the first 10 B-side density and second 10 The density of surface B is fitted to calibrate the third boron-aluminum standard sample. 10 The density of surface B includes selecting the first 10 B-surface density and second 10 The lower value of the density on the B-side is used to calibrate the boron-aluminum standard sample. 10 B-surface density.

[0010] Furthermore, the statement based on different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 The density of the B-side includes the density of pure B4C samples determined using chemical methods. 10 B-plane density; measuring different [areas] using neutron decay tests. 10 Neutron transmittance of pure B4C samples with different B-plane densities; establishing different neutron transmittance of pure B4C samples. 10 The curve showing the relationship between B-plane density and different neutron penetration rates.

[0011] Furthermore, the statement based on different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 The B-plane density also includes measuring the neutron transmittance of the boron-aluminum standard sample using a neutron attenuation test; and interpolating the relationship curve based on the neutron transmittance of the boron-aluminum standard sample to obtain the second density of the boron-aluminum standard sample. 10B-surface density.

[0012] Furthermore, the thickness of the pure B4C sample is 0.4~1.6 mm, and the density is ≥99%.

[0013] Furthermore, the pure B4C sample has a grain size ≤10μm and a size ≥50mm×50mm.

[0014] Furthermore, the first total boron content and the first... 10 The B abundance includes acid dissolution of boron-aluminum standard samples to obtain B4C residue powder and solution, and testing of the B4C residue powder and solution to obtain the first total boron content and the first... 10 B abundance.

[0015] Furthermore, the B4C content is obtained based on the first total boron content, and the obtained B4C content = total boron content × 1.2778.

[0016] Furthermore, the statement based on the first total boron content and the first... 10 The abundance of B was obtained from the first boron-aluminum standard sample. 10 In the density of B-surface, the first 10 The density of surface B is:

[0017] in, The density of the boron-aluminum standard sample; The thickness of the boron-aluminum standard sample; B4Cwt% is the weight percentage of B4C; Bwt% is the weight percentage of total boron in B4C; 10 Bwt% is 10 B abundance.

[0018] Furthermore, the minimum density of the boron-aluminum composite plate in the boron-aluminum standard sample is not less than 2.62 g / cm³. 3 In the boron-aluminum standard sample 10 B abundance is greater than or equal to 19.6%.

[0019] By applying the above-described technical solution of the present invention, at least the following technical effects are achieved: 1. This method employs two different and independent pathways to obtain a series of boron-aluminum standard samples: a chemical method and a hot-pressing pure B4C standard comparison method. 10 The density of the B-plane was verified by first-order linear fitting, and finally the series of boron-aluminum standard samples were calibrated. 10 The density of the B-side ensures the reliability and accuracy of neutron absorption performance testing for engineering boron-aluminum plates; 2. This method measures different 10 A series of pure B4C samples with B-surface density were used to obtain a series of boron-aluminum standard samples.10 B-plane density ensures that neutron-absorbing materials can work effectively under various operating conditions, thereby improving the overall safety of nuclear energy utilization; 3. The series of boron-aluminum standard samples prepared by this method meet strict regulatory nuclear standards. By verifying the performance of neutron-absorbing materials, the service life of the materials can be predicted, reasonable maintenance and replacement plans can be formulated, and the operating life of nuclear facilities can be extended. 4. This method obtains more accurate values ​​by comparing the chemical method and the neutron decay method, thus ensuring the reliability and accuracy of the neutron absorption performance test of the engineering boron aluminum plate; 5. This method solves the problem of traceability, allowing it to be traced back to pure boron carbide. The preparation process of pure boron carbide is mature and there are ASTM standard testing methods.

[0020] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0021] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A flowchart of a method for calibrating a series of boron-aluminum standard samples according to an embodiment is provided; Figure 2 A pure B4C sample from one embodiment is shown. 10 A schematic diagram showing the relationship between B-side density and different neutron transmittance curves; Figure 3 An example is presented showing a series of boron-aluminum standard samples obtained by two methods. 10 A schematic diagram illustrating the fitting of the density of surface B; Figure 4 A detailed flowchart of a series of boron-aluminum standard sample calibration method according to one embodiment is presented. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] The present invention will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed by the present invention.

[0024] Example

[0025] According to one aspect of the present invention, a method for calibrating a series of boron-aluminum standard samples is proposed.

[0026] like Figure 1 The figure illustrates a method for calibrating a series of boron-aluminum standard samples according to an embodiment of the present invention. The process mainly includes the following steps: S1. The first total boron content and the first... 10 B abundance.

[0027] Prior to step S1, the preparation of boron-aluminum standard samples is also included. The boron-aluminum standard samples should be prepared by mixing 6061 aluminum alloy powder with Type 1 B4C powder as specified in ASTM C750-2018 through powder metallurgy or other equivalent metal material preparation processes. The B4C powder content is 31 wt%, the particle size should be ≤44 μm, and the Fe content should be ≤0.5 wt%. The chemical composition of the 6061 aluminum alloy powder should meet the requirements of Table 1.

[0028] Table 1

[0029] The finished boron-aluminum standard test specimens should meet the following requirements: (1) The minimum density of boron-aluminum composite plates shall not be less than 2.62 g / cm³. 3 ; (2) 10 The abundance (percentage of atoms) of B should be greater than or equal to 19.6%.

[0030] Further, the boron-aluminum standard sample was dissolved in acid to obtain B4C residue powder and solution. The B4C residue powder and solution were tested to obtain the first total boron content and the first... 10 B abundance.

[0031] Furthermore, the B4C content is obtained based on the first total boron content, and the obtained B4C content = total boron content × 1.2778.

[0032] Specifically, in this embodiment, a chemical method is used to obtain B4C residue powder and solution by acid dissolution of a boron-aluminum standard sample. The total boron content in the B4C residue powder and solution is tested according to ASTM C791. 10 B abundance, where total boron content includes acid-soluble and acid-insoluble boron, B4C content = total boron content × 1.2778, and finally the abundance of a series of boron-aluminum standard samples was obtained through calculation. 10 B-surface density.

[0033] S2, based on the first total boron content and the first 10 The abundance of B was obtained from the first boron-aluminum standard sample. 10 B-surface density.

[0034] Furthermore, the first10 The density of surface B is:

[0035] in, The density of the boron-aluminum standard sample; The thickness of the boron-aluminum standard sample; B4Cwt% is the weight percentage of B4C; Bwt% is the weight percentage of total boron in B4C; 10 Bwt% is 10 B abundance.

[0036] The total boron content was determined by inductively coupled plasma atomic emission spectrometry. 10 The abundance of B was determined by thermal ionization mass spectrometry.

[0037] S3, according to different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 B-surface density.

[0038] Furthermore, the thickness of the pure B4C sample was 0.4~1.6 mm, and the density was ≥99%.

[0039] Furthermore, the grain size of the pure B4C sample is ≤10μm and the dimensions are ≥50mm×50mm.

[0040] Specifically, in this embodiment, the sample used for the hot-pressed pure B4C sample comparison method should be prepared by hot pressing of Type 1 B4C powder in ASTM C750-2018, wherein the particle size of the B4C powder should be ≤44μm and the Fe content should be ≤0.5wt%.

[0041] Pure B4C samples should meet the following requirements: Thickness range: 0.4~1.6mm (pure B4C sample) 10 B-side density coverage series boron-aluminum standard samples 10 (B-surface density); Pure B4C samples have a density ≥99%; Pure B4C samples have a grain size ≤10μm; Pure B4C sample size ≥ 50mm × 50mm.

[0042] Furthermore, the total boron content of the pure B4C sample was tested using chemical analysis methods (ASTM C791). 10 B abundance, obtained 10 B-plane density. Pure B4C sample. 10 The formula for calculating the density of surface B is shown below:

[0043] in, The density of a pure B4C board; The thickness of the pure B4C board; B4Cwt% is the weight percentage of B4C; Bwt% is the weight percentage of total boron in B4C; 10 Bwt% is 10 B abundance.

[0044] The total boron content was determined by inductively coupled plasma atomic emission spectrometry. 10 The abundance of B was determined by thermal ionization mass spectrometry.

[0045] Furthermore, a series of boron-aluminum standards were determined by comparison with pure B4C samples. 10 The steps for B-surface density include: Determination of pure B4C samples using chemical methods 10 B-side density; Measuring different neutron decay experiments 10 Neutron transmittance of a pure B4C sample with B-side density; Establish different pure B4C samples 10 The curve showing the relationship between B-plane density and different neutron transmittance; Neutron transmittance of boron-aluminum standard samples was measured using a neutron decay test. Based on the neutron transmittance of the boron-aluminum standard sample, interpolation is performed on the aforementioned relationship curve to obtain the second value of the boron-aluminum standard sample. 10 B-surface density.

[0046] Specifically, in this embodiment, based on known different 10 A series of pure B4C samples with B-plane density were used to determine the density of a series of boron-aluminum standard samples using neutron decay tests. 10 B-side density, detailed process is as follows: (1) Determine the series of pure B4C samples 10 B-surface density (determined using the preceding chemical method); (2) Neutron decay test to determine different 10 Neutron transmittance of pure B4C sample with B-side density; The aluminum sheet thickness corresponding to different thicknesses of pure B4C samples was calculated based on a boron-aluminum standard sample with a 31% B4C content. During neutron attenuation testing, pure B4C samples should be stacked with aluminum sheets of the corresponding thickness. The neutron absorption cross-section was physically simulated, and the neutron transmittance was used to infer the thickness of the aluminum sheet. 10 The density of the B-side is compared with the value in step (1) to determine the relative positional relationship between the pure B4C sample and the aluminum sheet; (3) Establish pure B4C samples (stacked aluminum sheets) with different 10 The relationship curve between B-plane density and different neutron transmittance, such as Figure 2 As shown; (4) The neutron transmittance of a series of boron-aluminum standard samples was measured using the same neutron attenuation test; (5) Based on the neutron transmittance measurement results of a series of boron-aluminum standard samples, in pure B4C samples... 10 Interpolate on the B-plane density-neutron transmittance curve; (6) The second series of boron-aluminum standard samples were obtained 10 B-surface density.

[0047] S4, regarding the first 10 B-surface density and second 10 The density of surface B is fitted to calibrate the boron-aluminum standard sample. 10 B-surface density.

[0048] Furthermore, select the first 10 B-surface density and second 10 The lower value of the density on the B-side is used to calibrate the boron-aluminum standard sample. 10 B-surface density.

[0049] Specifically, in this embodiment, a series of boron-aluminum standard samples were obtained through two different independent methods: the chemical method and the hot-pressed pure B4C sample comparison method. 10 B-surface density, and perform a first-order linear fit between the two. For example... Figure 3 As shown, a series of boron-aluminum standard samples were obtained by chemical methods. 10 Using the density of surface B as the abscissa, a series of boron-aluminum standard samples were obtained by comparing them with hot-pressed pure B4C samples. 10 Using the density of surface B as the ordinate, a series of boron-aluminum standard samples were examined. 10 The consistency between the two methods for B-surface density led to a conservative selection. 10 Calibrate a series of boron-aluminum standard samples with lower density values ​​on the B-side. 10 B-surface density.

[0050] like Figure 4 A detailed flowchart of a series of boron-aluminum standard sample calibration methods in this embodiment is presented.

[0051] By applying the above-described technical solution of the present invention, at least the following technical effects are achieved: 1. This method employs two different and independent pathways to obtain a series of boron-aluminum standard samples: a chemical method and a hot-pressing pure B4C standard comparison method. 10 The density of the B-plane was verified by first-order linear fitting, and finally the series of boron-aluminum standard samples were calibrated. 10 The density of the B-side ensures the reliability and accuracy of neutron absorption performance testing for engineering boron-aluminum plates; 2. This method measures different 10 A series of pure B4C samples with B-surface density were used to obtain a series of boron-aluminum standard samples. 10B-plane density ensures that neutron-absorbing materials can work effectively under various operating conditions, thereby improving the overall safety of nuclear energy utilization; 3. The series of boron-aluminum standard samples prepared by this method meet strict regulatory nuclear standards. By verifying the performance of neutron-absorbing materials, the service life of the materials can be predicted, reasonable maintenance and replacement plans can be formulated, and the operating life of nuclear facilities can be extended. 4. This method obtains more accurate values ​​by comparing the chemical method and the neutron decay method, thus ensuring the reliability and accuracy of the neutron absorption performance test of the engineering boron aluminum plate; 5. This method solves the problem of traceability, allowing it to be traced back to pure boron carbide. The preparation process of pure boron carbide is mature and there are ASTM standard testing methods.

[0052] The above are merely several specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

[0053] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0054] It should be noted that, in the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. A method for calibrating a series of boron-aluminum standard samples, characterized in that, include: The first total boron content and the first... were obtained by testing the boron-aluminum standard sample. 10 B abundance; Based on the first total boron content and the first 10 The abundance of B was obtained from the first boron-aluminum standard sample. 10 B-side density; According to different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 B-side density; For the first 10 B-surface density and second 10 The density of surface B is fitted to calibrate the boron-aluminum standard sample. 10 B-surface density.

2. The calibration method according to claim 1, characterized in that, The first 10 B-surface density and second 10 The density of surface B is fitted to calibrate the third boron-aluminum standard sample. 10 In the density of surface B, include, Select the first 10 B-surface density and second 10 The lower value of the density on the B-side is used to calibrate the boron-aluminum standard sample. 10 B-surface density.

3. The calibration method according to claim 1, characterized in that, According to different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 The density of surface B includes, Determination of pure B4C samples using chemical methods 10 B-side density; Measuring different neutron decay experiments 10 Neutron transmittance of a pure B4C sample with B-side density; Establish different pure B4C samples 10 The curve showing the relationship between B-plane density and different neutron penetration rates.

4. The calibration method according to claim 3, characterized in that, According to different 10 The second boron-aluminum standard sample was determined by the B-surface density of the pure B4C sample. 10 The density of surface B also includes, Neutron transmittance of boron-aluminum standard samples was measured using a neutron decay test. Based on the neutron transmittance of the boron-aluminum standard sample, interpolation is performed on the aforementioned relationship curve to obtain the second value of the boron-aluminum standard sample. 10 B-surface density.

5. The calibration method according to claim 1, characterized in that, The thickness of the pure B4C sample is 0.4~1.6 mm, and the density is ≥99%.

6. The calibration method according to claim 1, characterized in that, The pure B4C sample has a grain size ≤10μm and a size ≥50mm×50mm.

7. The calibration method according to claim 1, characterized in that, The first total boron content and the first [unclear] were obtained by testing the boron-aluminum standard sample. 10 B abundance includes, Acid dissolution of boron-aluminum standard samples yielded B4C residue powder and a solution. Testing of the B4C residue powder and solution yielded the first total boron content and the first... 10 B abundance.

8. The calibration method according to claim 7, characterized in that, The B4C content is obtained based on the first total boron content, and the obtained B4C content = total boron content × 1.2778.

9. The calibration method according to claim 1, characterized in that, The first total boron content and the first 10 The abundance of B was obtained from the first boron-aluminum standard sample. 10 In the density of B-surface, the first 10 The density of surface B is: in, The density of the boron-aluminum standard sample; The thickness of the boron-aluminum standard sample; B4Cwt% is the weight percentage of B4C; Bwt% is the weight percentage of total boron in B4C; 10 Bwt% is 10 B abundance.

10. The calibration method according to claim 1, characterized in that, The minimum density of the boron-aluminum composite plate in the boron-aluminum standard sample is not less than 2.62 g / cm³. 3 In the boron-aluminum standard sample 10 B abundance is greater than or equal to 19.6%.

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