Method for processing and recycling mechanical fracture sample after irradiation

Abstract

The invention relates to the technical field of post-irradiation mechanical sample processing, and provides a post-irradiation mechanical fracture sample processing and recycling method which comprises the following steps: selecting a metal sample which is subjected to neutron irradiation and is fractured after finishing a Charpy impact test or a fracture toughness test; a linear cutting machining mode is adopted, a plastic deformation area at the fracture of the broken metal sample is removed, and a machining unit body in a regular geometrical shape is obtained; detecting the processing unit body by adopting a Vickers hardness detection method; according to the actual size of the machining unit body, machining positions and machining directions of the small-size samples are planned; machining the machining unit bodies into a plurality of small-size samples in a machining manner; after machining is completed, the size of the small-size sample is detected in a non-contact mode through an optical measuring device; and carrying out mechanical property test on the small-size sample by using load test equipment. According to the method, dozens of small-size samples are processed from one standard fracture sample, and the utilization rate of the samples is increased.

Description

Technical Field

[0001] This application relates to the field of post-irradiation mechanical specimen processing technology, and more specifically, to a method for processing and reusing post-irradiation mechanically fractured specimens. Background Technology

[0002] Currently, traditional post-irradiation mechanical property testing typically employs destructive testing with standard-sized specimens, such as Charpy impact tests or fracture toughness tests. Neutron irradiation experiments are costly, time-consuming, and limited by the irradiation space, resulting in a very limited number of test specimens. Data can only be obtained from a single test per specimen, and due to the dispersion of material properties and experimental uncertainties, single-point data is insufficient to accurately evaluate the mechanical properties of materials under irradiation. The large number of radioactive fractured specimens generated after the tests are usually disposed of as nuclear waste, increasing radioactive waste management costs and wasting valuable irradiated materials. Currently, research on the reuse technology of post-irradiation fractured specimens is still immature both domestically and internationally. No mature mechanical processing reuse methods are found in the published literature, while methods such as welding reconstruction have problems such as heat-affected zones, changes in material properties, high technical requirements, and unsuitability for strong radioactive environments, making safe and efficient implementation in hot chambers difficult. Summary of the Invention

[0003] This application aims to at least address the problem in related technologies that neutron-irradiated samples are highly radioactive and are usually disposed of as nuclear waste after the test, leading to increased radioactive waste management costs and waste of irradiated materials.

[0004] To solve the above-mentioned technical problems, this application is implemented as follows: This application provides a method for reprocessing and reusing mechanically fractured specimens after irradiation. The method involves reprocessing metal specimens that have fractured under a radioactive environment through mechanical testing. The steps include: selecting metal specimens that have undergone neutron irradiation and have completed Charpy impact or fracture toughness tests, with the fractured specimens retaining areas that have not undergone plastic deformation; removing the plastic deformation zone at the fracture surface of the fractured metal specimen using wire cutting to obtain a processing unit with a regular geometric shape; testing the processing unit using Vickers hardness testing to ensure that the plastic deformation zone has been completely removed and the material properties have not changed; measuring the actual dimensions of the processing unit; and, based on the actual dimensions of the processing unit, using a computer simulation algorithm to plan the processing positions and directions of multiple small-sized specimens; processing the processing unit into multiple small-sized specimens using a remotely controlled machining system within a hot chamber, according to the planned processing positions and directions; after processing, using an optical measuring device to non-contactly measure the dimensions of the small-sized specimens to ensure that the processing accuracy meets the test requirements; and using a load testing device to conduct mechanical property tests on the small-sized specimens to obtain the mechanical property data of the processed material.

[0005] This application provides a method for processing and reusing mechanically fractured specimens after irradiation. The method employs a technical approach of "remote machining within a hot chamber, precise removal of the plastic deformation zone, computer simulation optimization of sample arrangement, and precision machining using a combination of multiple processes." First, wire cutting is used to precisely remove the plastic deformation zone of the fractured specimen, retaining the elastic deformation zone with unchanged properties as the processing unit. Second, optimization algorithms such as genetic algorithms are used to perform three-dimensional simulation and sample arrangement of the processing unit, maximizing material utilization. Subsequently, a multi-axis CNC machine tool is used to remotely perform a combination of turning, milling, grinding, and wire cutting within the hot chamber, efficiently and accurately processing the processing unit into multiple small-sized specimens conforming to international standards. Finally, non-contact optical measurement and a micro-testing machine are used to complete the testing and mechanical property analysis. This method enables the processing of dozens of small-sized specimens from a single standard fractured specimen, increasing specimen utilization by over 70%. While completely avoiding heat-affected zones and ensuring the original material properties, it significantly increases the amount of experimental data and improves the reliability of results. Simultaneously, it reduces the generation of radioactive waste at the source, solving the problems of precious irradiated specimens, unreliable data from single specimens, high testing costs, and radioactive waste disposal.

[0006] Additional aspects and advantages of this application will become apparent in the following description or may be learned by practice of this application. Attached Figure Description

[0007] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart illustrating a method for processing and reusing an irradiated mechanically fractured specimen according to an embodiment of this application. Figure 2 This is one of the specific processing diagrams of a method for processing and reusing mechanically fractured irradiated specimens in one embodiment of this application; Figure 3 This is a second schematic diagram illustrating the specific processing method for processing and reusing mechanically fractured irradiated specimens in one embodiment of this application. Figure 4 This is the third schematic diagram of a specific processing method for processing and reusing mechanically fractured specimens after irradiation, as described in one embodiment of this application.

[0008] in, Figures 2 to 4 The correspondence between the reference numerals and component names in the attached drawings is as follows: 200 Impact specimen after fracture, 210 Plastic deformation zone, 220 Machining unit, 230 Small-sized sheet tensile specimen, 240 Small-sized bending specimen, 300 Compact tensile specimen after fracture, 310 Plastic deformation zone, 320 Machining unit, 330 Small-sized compact tensile specimen. Detailed Implementation

[0009] To better understand the above-mentioned objectives, features, and advantages of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0010] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of this application is not limited to the specific embodiments disclosed below.

[0011] The following reference Figures 1 to 4 This application describes a method for processing and reusing irradiated mechanically fractured specimens according to some embodiments of the present application.

[0012] like Figures 1 to 4 As shown, Figure 1 This is a flowchart illustrating a method for processing and reusing an irradiated mechanically fractured specimen according to an embodiment of this application. Figure 2 This is one of the specific processing diagrams of a method for processing and reusing mechanically fractured irradiated specimens in one embodiment of this application; Figure 3 This is a second schematic diagram illustrating the specific processing method for processing and reusing mechanically fractured irradiated specimens in one embodiment of this application. Figure 4 This is the third schematic diagram of a specific processing method for processing and reusing mechanically fractured specimens after irradiation, as described in one embodiment of this application.

[0013] like Figure 1As shown, one embodiment of this application provides a method for reprocessing and reusing mechanically fractured specimens after irradiation. This method is used to reprocess metal specimens that have fractured under a mechanical test in a radioactive environment. The steps include: selecting a metal specimen that has been irradiated with neutrons and has undergone a Charpy impact test or fracture toughness test, where the fractured metal specimen retains areas that have not undergone plastic deformation; using wire cutting to remove the plastic deformation zone at the fracture surface of the fractured metal specimen, obtaining a processing unit with a regular geometric shape; and using Vickers hardness testing to inspect the processing unit to ensure that the plastic deformation zone has been completely removed and the material... The performance remained unchanged. The actual dimensions of the processing unit were measured, and based on these dimensions, a computer simulation algorithm was used to plan the processing positions and directions of multiple small-sized specimens. According to the planned processing positions and directions, the processing unit was processed into multiple small-sized specimens using a remotely controlled machining system within the hot chamber. After processing, an optical measuring device was used to perform non-contact measurement of the dimensions of the small-sized specimens to ensure that the processing accuracy met the test requirements. A load testing device was used to conduct mechanical property tests on the small-sized specimens to obtain the mechanical property data of the processed material.

[0014] This application provides a method for processing and reusing mechanically fractured specimens after irradiation. The method employs a technical approach of "remote machining within a hot chamber, precise removal of the plastic deformation zone, computer simulation optimization of sample arrangement, and precision machining using a combination of multiple processes." First, wire cutting is used to precisely remove the plastic deformation zone of the fractured specimen, retaining the elastic deformation zone with unchanged properties as the processing unit. Second, optimization algorithms such as genetic algorithms are used to perform three-dimensional simulation and sample arrangement of the processing unit, maximizing material utilization. Subsequently, a multi-axis CNC machine tool is used to remotely perform a combination of turning, milling, grinding, and wire cutting within the hot chamber, efficiently and accurately processing the processing unit into multiple small-sized specimens conforming to international standards. Finally, non-contact optical measurement and a micro-testing machine are used to complete the testing and mechanical property analysis. This method enables the processing of dozens of small-sized specimens from a single standard fractured specimen, increasing specimen utilization by over 70%. While completely avoiding heat-affected zones and ensuring the original properties of the material, it significantly increases the amount of experimental data, improves the reliability of results, and simultaneously reduces the generation of radioactive waste at the source.

[0015] Specifically, currently, the design, screening, and verification of new fuels and materials, as well as the safe operation, monitoring, and life assessment of in-service reactors, all rely heavily on the technical and data support of irradiation performance evaluation. For example, irradiation monitoring tubes are installed in pressurized water reactors of nuclear power plants to obtain the mechanical properties of the reactor pressure vessel core belt zone materials after irradiation, providing data for the safety analysis of the reactor pressure vessel. The lifespan of operating nuclear power plants is generally no more than 40 years, and life extension is now an inevitable trend. However, many nuclear power plants have no new irradiation monitoring samples available to assess the integrity of the reactor pressure vessel at the end of their lifespan. Material mechanical property testing is generally destructive testing; a single sample can only yield data from one test. The inherent uncertainty of the test reduces the reliability of a single test result, so material mechanical testing generally requires multiple samples to evaluate performance indicators. Neutron irradiation testing is costly and time-consuming, and irradiated samples are precious and limited in number. Neutron irradiated samples are highly radioactive and are often permanently stored as radioactive solid waste after the test, leading to increased radioactive waste management costs and the waste of irradiated materials.

[0016] To address the shortcomings of existing technologies and the significant waste of resources caused by using irradiated samples only once, this application provides a method for processing and reusing mechanically fractured irradiated samples.

[0017] like Figure 1 As shown, this application proposes a method for processing and reusing mechanically fractured specimens after irradiation, used to reprocess metal specimens that have fractured under mechanical testing in a radioactive environment. The specific method steps are as follows: S102, select a metal specimen that has been irradiated by neutrons and has been broken after Charpy impact test or fracture toughness test, and the broken metal specimen retains an area that has not undergone plastic deformation. S104 uses wire cutting to remove the plastic deformation zone at the fracture surface of the broken metal sample, obtaining a processing unit with a regular geometric shape. S106 uses the Vickers hardness test method to test the processed unit to ensure that the plastic deformation zone has been completely removed and the material properties have not changed. S108, Measure the actual size of the processing unit, and based on the actual size of the processing unit, use a computer simulation arrangement algorithm to plan the processing position and processing direction of multiple small-sized samples; S110, according to the planned processing position and processing direction, uses a remotely controlled machining system in the hot chamber to process the processing unit into multiple small-sized samples by machining. S112. After processing, an optical measuring device is used to perform non-contact detection on the dimensions of small-sized samples to ensure that the processing accuracy meets the test requirements. S114, Use load testing equipment to conduct mechanical property tests on small-sized specimens to obtain mechanical property data of the processed material.

[0018] Specifically, such as Figure 1 As shown, wire EDM ensures the accuracy and consistency of plastic deformation zone removal; Vickers hardness testing effectively verifies the unchanged material properties; computer simulation and arrangement algorithms maximize material utilization through processing path optimization; a remotely controlled machining system within the hot chamber ensures the safety and feasibility of processing operations in a highly radioactive environment; non-contact optical measurement avoids sample contamination and ensures dimensional accuracy; and load testing ultimately obtains multiple valid mechanical property data. Through the synergistic cooperation of these steps, this method significantly improves the utilization rate of irradiated samples and the reliability and statistical significance of experimental data while completely avoiding secondary thermal effects, and simultaneously reduces the generation of radioactive waste at the source. It solves the problems of precious irradiated samples, unreliable data from single samples, high testing costs, and radioactive waste disposal.

[0019] Specifically, the purpose of this application is to provide a method for processing and reusing mechanically fractured specimens after irradiation. The method involves mechanically processing radioactive metallic specimens after fracture within a hot chamber, reusing them by processing a large fractured specimen into several smaller specimens, thus obtaining a multiple number of new specimens. This is achieved through a relatively simple and easily quality-controlled mechanical processing method, significantly improving the utilization rate of irradiated specimens, obtaining more experimental data, increasing the reliability of experimental results, and reducing the cost of obtaining post-irradiation performance data. Compared with existing technologies, the beneficial effects of this application are: First, neutron irradiation of specimens is expensive and time-consuming; irradiated specimens are precious and limited in number, and processing and reuse can significantly improve the utilization rate of irradiated specimens. Second, a certain number of small-sized irradiated specimens can be obtained relatively easily through mechanical processing. Third, a multiple number of new irradiated specimens can be obtained, thereby obtaining more experimental data and increasing the reliability of experimental results. Fourth, irradiated specimens are highly radioactive, and the cost of disposing of them as solid radioactive waste after the experiment is high; processing and reusing fractured specimens can reduce the generation of radioactive waste at the source. Fifth, the newly made small-sized sample has a significantly reduced volume compared to the original sample, thus greatly reducing its radioactivity, which helps to reduce the construction cost of radioactive testing facilities.

[0020] In practical applications, radioactive metallic materials refer to metallic materials formed by neutron irradiation of the sample. Larger samples refer to Charpy impact specimens, typically with dimensions of 10mm × 10mm × 55mm, according to GB / T229-2000 "Metallic Materials - Charpy Pendulum Impact Test Method" or compact tensile specimens, typically with dimensions of 60.96mm × 63.5mm × 25.4mm (sizes can be scaled proportionally according to GB / T21143-2014 "Unified Test Method for Quasi-Static Fracture Toughness of Metallic Materials"). Fractured specimens refer to the two fragments of a Charpy impact specimen after the impact test or the two fragments of a compact tensile specimen after the fracture toughness test. Relatively smaller specimens generally refer to small-sized bending specimens, small-sized thin-sheet tensile specimens, and small-sized compact tensile specimens, etc., which can be selected based on actual application conditions and will not be listed here.

[0021] In some embodiments, wire cutting may be used to remove the plastic deformation zone at the fracture surface of the broken metal sample to obtain a processing unit with a regular geometric shape. Specifically, the removal position of the wire cutting is at least 5 mm away from the fracture surface of the broken metal sample to ensure complete removal of the plastic deformation zone.

[0022] Specifically, by setting the removal position of wire cutting at least 5 mm from the fracture surface, all plastic deformation and property change areas caused by the initial mechanical test can be scientifically and thoroughly removed, ensuring that the material properties of the obtained processed unit are consistent with those of the unstressed area of ​​the original irradiated sample. This distance parameter is a conservative safety value derived from a systematic study of the depth distribution of plastic deformation zones in various metallic materials, ensuring both complete removal of the affected area and maximum retention of usable material. This specific limitation fundamentally guarantees that all subsequently processed small-sized samples can accurately reflect the original post-irradiation mechanical properties of the material, avoiding data distortion caused by residual plastic deformation zones.

[0023] In practical applications, the removal position of wire cutting can be set at a distance of 5mm, 7mm, 9mm, and 15mm from the break, depending on the specific circumstances. These options can be selected based on the actual application and will not be listed here.

[0024] In some embodiments, optionally, a computer simulation arrangement algorithm is used to plan the processing positions and directions of multiple small-sized samples. Specifically, the computer simulation arrangement algorithm uses a genetic algorithm or a simulated annealing algorithm to plan the processing path of the broken metal sample in order to optimize the utilization rate of the processing unit.

[0025] Specifically, by employing intelligent optimization algorithms such as genetic algorithms or simulated annealing algorithms, mathematical modeling and computational simulation of the three-dimensional geometry of the processing unit are performed. This allows for the autonomous and adaptive search and determination of the optimal spatial arrangement and processing path sequence for multiple small-sized samples within the processing unit. These algorithms possess global optimization capabilities, effectively avoiding getting trapped in local optima. Thus, under complex geometric constraints, the utilization rate of the irradiated material is maximized, ensuring that the maximum number of small-sized samples meeting standard requirements can be processed from a limited number of processing units. Simultaneously, the optimized processing path reduces processing time and tool wear, thereby improving the economic efficiency of the entire reprocessing process while maintaining data output.

[0026] In some embodiments, the plurality of small-sized specimens may optionally include: small-sized bending specimens, small-sized sheet tensile specimens, or small-sized compact tensile specimens.

[0027] Specifically, the design and selection of small-sized bending specimens, small-sized sheet tensile specimens, and small-sized compact tensile specimens are based on small specimen specifications that have been widely validated in international standards such as ASTM and ISO, or in publicly available mature cases. This allows for the effective acquisition of key mechanical property parameters such as tensile strength, yield strength, elongation, and fracture toughness of materials using a miniature testing machine. This enables the simultaneous acquisition of multiple types of mechanical property data from a single fractured standard specimen, greatly enriching the dimensions and statistical significance of the experimental data, improving the comprehensiveness and reliability of the evaluation of irradiated material properties, and avoiding the consumption of irradiated specimens to obtain different performance data, thus saving significant testing costs.

[0028] In some embodiments, optionally, a load testing device is used to perform mechanical property tests on small-sized specimens to obtain mechanical property data of the processed material. Specifically, this includes: performing bending tests or fracture toughness tests on small-sized bending specimens in a hot chamber, performing tensile tests on small-sized thin sheet tensile specimens, and performing fracture toughness tests on small-sized compact tensile specimens.

[0029] Specifically, by remotely conducting bending, tensile, and fracture toughness tests on small-sized specimens using specialized micro-load testing equipment in a hot chamber environment, key mechanical property data of irradiated materials under different stress states can be safely and accurately obtained, including flexural strength and modulus, tensile strength and yield strength, and fracture toughness parameters. This fully utilizes the reprocessed small-sized specimens, enabling standardized testing of various mechanical properties under a highly radioactive confinement environment. It expands the data output and data types of individual original fractured specimens, providing a data foundation for a comprehensive and reliable evaluation of the performance degradation behavior of materials under irradiation, while avoiding the risk of direct exposure to radioactivity for personnel, ensuring the safety and feasibility of the experimental operation.

[0030] In some embodiments, the load testing equipment is optionally a miniature mechanical testing machine, which can be operated remotely within a hot chamber, with a maximum load not exceeding 5 kN.

[0031] Specifically, the load testing equipment is limited to a miniature mechanical testing machine with a maximum load not exceeding 5 kN. This load range was determined based on theoretical calculations and experimental verification of the fracture strength of small-sized specimens such as thin sheet tensile and micro-bending specimens, and can fully meet the load requirements for their mechanical property testing. On the one hand, the miniaturized equipment is easier to integrate into space-constrained hot chamber environments and achieves precise remote control, ensuring the feasibility of testing in highly radioactive environments. On the other hand, the lower load capacity, matched with the low fracture force of small specimens, can provide higher load measurement resolution and control accuracy, thereby significantly improving the testing accuracy and reliability of key mechanical property parameters such as tensile, bending, and fracture toughness.

[0032] In some embodiments, the machining system may optionally include a multi-axis CNC machine tool, which performs precise positioning and machining in a heated chamber via a remote vision system.

[0033] Specifically, the machining system employs a multi-axis CNC machine tool and integrates a high-precision remote vision system. This vision system uses a radiation-resistant industrial camera to capture images and positional information of the machining unit in real time and feeds the data back to the CNC system to automatically correct the machine tool coordinates and machining path. In this way, even in a highly radioactive hot chamber environment inaccessible to personnel, sub-millimeter-level positioning accuracy and centering requirements for precision machining of small-sized samples are achieved. This overcomes the difficulties of traditional template-based or manual positioning in a radioactive environment, ensuring that the combined implementation of multiple machining processes such as turning, milling, and grinding can be completed efficiently and accurately. This guarantees that the final small-sized samples have consistent geometric dimensions and form and position tolerances, meeting the requirements for sample machining quality in subsequent mechanical property tests.

[0034] In some embodiments, the precise positioning and processing can be performed in the heated chamber using a remote vision system. Specifically, this includes: acquiring real-time images of the processing unit using an industrial camera, comparing them with a processing path generated by a preset computer simulation algorithm, and automatically correcting the coordinate zero point and processing path of the machining system.

[0035] Specifically, high-resolution industrial cameras are used to acquire multi-angle images of the machining unit in real time. Image processing algorithms extract its actual contour and position coordinates, and this data is compared with the ideal machining path pre-generated by a computer simulation algorithm. When pose deviations exist, the system automatically calculates compensation and drives the CNC machine tool to adjust the coordinate zero point and machining path trajectory. This achieves automatic calibration of the machining reference and dynamic closed-loop control of the machining process in a strongly radioactive hot chamber isolation environment, completely eliminating machining deviations caused by blind spots in remote operation or positioning and clamping errors, and ensuring high relative positional accuracy and dimensional consistency of multiple small-sized samples during complex machining processes.

[0036] In some embodiments, optionally, the processing unit body is processed into multiple small-sized samples by a remotely controlled machining system in the hot chamber. Specifically, this includes processing the processing unit body into multiple small-sized samples by a combination of turning, milling, grinding and wire cutting processes using a remotely controlled multi-axis CNC machine tool in the hot chamber.

[0037] Specifically, multi-axis linkage CNC machine tools integrate and execute a combination of turning, milling, grinding, and wire cutting processes through remote control. By organically combining multiple processing technologies and precisely controlling the CNC program, irregularly shaped processing units can be efficiently and accurately processed into multiple small-sized samples with complex geometric features and consistent dimensions in a strongly radioactive isolation environment. This not only meets the requirements of different types of samples for shape, size, and surface quality, but also avoids processing quality defects caused by the limitations of a single process, ensuring the accuracy and reliability of subsequent mechanical property test data.

[0038] In some embodiments, the optical measuring device may optionally be a laser scanner or a structured light 3D scanner, with a measurement accuracy of not less than ±0.01 mm.

[0039] Specifically, laser scanners or structured light 3D scanners use non-contact optical detection technology to quickly acquire high-density 3D point cloud data of small-sized sample surfaces and reconstruct accurate 3D digital models. By comparing these models with the original design model, key dimensions and geometric tolerances are automatically detected. This allows for rapid and high-precision full inspection of tiny, complex-shaped samples while completely avoiding contact with radioactive samples, thus eliminating contamination and damage. It ensures that the geometric dimensions and shape accuracy of every reused small-sized sample strictly meet international standards for mechanical property testing samples. Specific Implementation Example 1: like Figure 2 and Figure 3 As shown in the example below, the post-fracture impact specimen 200 is machined in a hot chamber after the metal material has fractured. One post-fracture impact specimen 200 is processed into 10 small-sized thin-sheet tensile specimens 230 and 10 small-sized bending specimens 240. The dimensions of the post-fracture impact specimen 200 are 55mm × 10mm × 10mm. The specific steps are as follows: Step 1: After the Charpy impact test, the specimen breaks into two parts. Take one part and impact it again at 200°. Step 2: Remove the plastic deformation zone 210 by wire cutting at a distance of 5mm from the fracture to obtain the processing unit 220; Step 3: Measure the dimensions of the processing unit 220, especially the part near the plastic deformation zone 210. Compared with the original complete Charpy impact specimen, the dimensions are not significantly different, ensuring that the plastic deformation zone 210 has been completely removed. Step 4: Based on the dimensions of the processing unit 220, design the shape and size of the small-sized sheet tensile specimen 230 and the small-sized bending specimen 240, and arrange the processing positions and orientations of the smaller specimens; the dimensions of the small-sized sheet tensile specimen 230 are 16mm×4mm×0.75mm, and the dimensions of the small-sized bending specimen 240 are 18mm×3.3mm×1.65mm. The shape and size of the small-sized specimens are consistent with those of international standards or publicly available mature foreign case studies. Step 5: Select machining methods such as turning, milling, grinding, and wire cutting to produce 10 small-sized thin sheet tensile specimens 230 and 10 small-sized bending specimens 240. Step 6: The small-sized thin sheet tensile specimen 230 is subjected to a tensile test in a hot chamber to obtain the tensile strength, yield strength and elongation of the material; Step 7: The small-sized bending specimen 240 is subjected to a bending test in a hot chamber. If a pre-crack is made, a fracture toughness test can also be performed. Specific Implementation Example 2: like Figure 4As shown in the example below, the compact tensile test specimen 300 of the fractured metal material is machined in a hot chamber, and one compact tensile test specimen 300 is processed into eight smaller compact tensile test specimens 330, as an example for illustration. The dimensions of the compact tensile test specimen 300 are: width W = 25.4 mm and thickness B = 12.7 mm. The specific steps are as follows: Step 1: After the fracture toughness test of the compact tensile specimen is completed, it breaks into two parts. Take one part and perform a compact tensile test on it for 300 mm. Step 2: Remove the plastic deformation zone 310 by wire cutting at a distance of 5mm from the fracture to obtain the processing unit 320; Step 3: Measure the dimensions of the processing unit 320, especially the part near the plastic deformation zone 310. Compare it with the original intact Charpy impact specimen. There is no significant change in size, which ensures that the plastic deformation zone 310 has been completely removed. Step 4: Based on the dimensions of the processing unit 320, design the shape and dimensions of the small compact tensile specimen 330, and arrange the processing positions and directions of the small compact tensile specimen 330; wherein, the dimensions of the small compact tensile specimen 330 are a width W of 8.33 mm and a thickness B of 4.17 mm. Step 5: Select machining methods such as turning, milling, grinding, and wire cutting to produce 8 small-sized compact tensile test specimens 330; Step 6: A set of 8 small-sized compact tensile specimens 330 were subjected to fracture toughness tests in a hot chamber.

[0042] In the description of this application, the term "multiple" refers to two or more. Unless otherwise expressly defined, the terms "upper," "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. The terms "connection," "installation," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0043] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which 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.

[0044] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for processing and reusing mechanically fractured irradiated specimens, characterized in that, The method for reprocessing metal samples that have broken under mechanical testing in a radioactive environment includes the following steps: Select a metal specimen that has been irradiated with neutrons and has been subjected to Charpy impact test or fracture toughness test and then broken, wherein the broken metal specimen retains an area that has not undergone plastic deformation. The plastic deformation zone at the fracture surface of the broken metal sample is removed by wire cutting to obtain a processing unit with a regular geometric shape; The Vickers hardness test method was used to test the processed unit to ensure that the plastic deformation zone had been completely removed and the material properties had not changed. The actual dimensions of the processing unit are measured, and based on the actual dimensions of the processing unit, a computer simulation arrangement algorithm is used to plan the processing positions and directions of multiple small-sized samples. According to the planned processing position and processing direction, the processing unit is processed into multiple small-sized samples in the hot chamber by a remotely controlled machining system. After processing, the dimensions of the small sample are non-contactly measured using an optical measuring device to ensure that the processing accuracy meets the test requirements. The mechanical properties of the small-sized specimen were tested using a load testing device to obtain mechanical property data of the processed material.

2. The method for processing and reusing mechanically fractured irradiated specimens according to claim 1, characterized in that, The wire cutting process removes the plastic deformation zone at the fracture surface of the broken metal sample to obtain a processed unit with a regular geometric shape, specifically including: The removal point of the wire cutting process is at least 5 mm away from the fracture surface of the broken metal sample to ensure complete removal of the plastic deformation-affected zone.

3. The method for processing and reusing mechanically fractured irradiated specimens according to claim 1, characterized in that, The method employs a computer simulation arrangement algorithm to plan the processing positions and directions of multiple small-sized samples, specifically including: The computer simulation permutation algorithm uses a genetic algorithm or a simulated annealing algorithm to plan the processing path of the broken metal sample in order to optimize the utilization rate of the processing unit.

4. The method for processing and reusing mechanically fractured irradiated specimens according to claim 1, characterized in that, The multiple small-sized specimens specifically include: small-sized bending specimens, small-sized thin sheet tensile specimens, or small-sized compact tensile specimens.

5. The method for processing and reusing mechanically fractured irradiated specimens according to claim 4, characterized in that, The process of using a load testing device to perform mechanical property tests on the small-sized sample to obtain mechanical property data of the processed material specifically includes: The small-sized bending specimen is subjected to bending test or fracture toughness test in a hot chamber, the small-sized thin sheet tensile specimen is subjected to tensile test, and the small-sized compact tensile specimen is subjected to fracture toughness test.

6. The method for processing and reusing mechanically fractured irradiated specimens according to claim 5, characterized in that, The load testing equipment is a miniature mechanical testing machine that can be operated remotely inside a hot chamber, with a maximum load not exceeding 5kN.

7. The method for processing and reusing mechanically fractured irradiated specimens according to claim 1, characterized in that, The machining system includes a multi-axis CNC machine tool, which performs precise positioning and machining in a heated chamber using a remote vision system.

8. The method for processing and reusing mechanically fractured irradiated specimens according to claim 7, characterized in that, The precise positioning and processing within the heated chamber using a remote vision system specifically includes: The real-time image of the processing unit is acquired by an industrial camera and compared with the processing path generated by a preset computer simulation algorithm. The coordinate zero point and processing path of the machining system are then automatically corrected.

9. The method for processing and reusing mechanically fractured irradiated specimens according to claim 7, characterized in that, The remotely controlled machining system within the hot chamber processes the machining unit into multiple small-sized samples using machining methods, specifically including: In the hot chamber, a multi-axis CNC machine tool under remote control is used to process the machining unit into multiple small-sized samples using a combination of turning, milling, grinding and wire cutting processes.

10. The method for processing and reusing mechanically fractured irradiated specimens according to claim 1, characterized in that, The optical measuring device is a laser scanner or a structured light 3D scanner, with a measurement accuracy of not less than ±0.01mm.

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