Test method

Abstract

The embodiment of the present application relates to the technical field of analyzing materials by measuring the chemical or physical properties of the materials, and particularly relates to a test method suitable for determining the compatibility between a new fuel and a new cladding, comprising: processing the new fuel and the new cladding to make them available for the test, vacuumizing a reaction space and cleaning the reaction space with high-purity inert gas, placing the processed new fuel and the new cladding together in the reaction space, inputting protective gas into the reaction space to reach a first predetermined pressure, heating the reaction space to a predetermined temperature and keeping the temperature for a predetermined time, adjusting the contact force between the new fuel and the new cladding during the heating and keeping stages, analyzing the microstructure of the two, and determining the compatibility between the new fuel and the new cladding. The method can accurately simulate the interaction relationship between the fuel and the cladding under actual working conditions, make the reaction between the new fuel and the new cladding closer to the actual situation, and thus improve the test precision and enhance the accuracy and reliability of the obtained test results.

Description

Technical Field

[0001] The embodiments of this application relate to the technical field of analyzing materials by measuring their chemical or physical properties, and specifically to a test method. Background Technology

[0002] The statements herein are provided merely as background information in connection with this application and do not necessarily constitute prior art.

[0003] Fuel-cladding compatibility refers to the absence of harmful chemical or physical reactions between fuel and cladding during the operation of fuel elements in a reactor, which could affect the integrity and safety of the fuel elements. Therefore, selecting fuel and cladding materials with good compatibility is one of the key factors in ensuring the safe operation of a nuclear reactor.

[0004] To determine whether the compatibility of fuel and cladding meets the requirements for safe operation in a reactor, tests need to be conducted beforehand. However, current methods for determining fuel and cladding compatibility still suffer from problems such as low test accuracy and unreliable test results. Summary of the Invention

[0005] A brief overview of this application is provided below to offer a basic understanding of certain aspects thereof. It should be understood that this overview is not an exhaustive summary of the application. It is not intended to identify key or essential parts of the application, nor is it intended to limit its scope. Its purpose is merely to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0006] An embodiment of this application provides a test method suitable for determining the compatibility between new fuel and new cladding, comprising the following steps: S00: processing the new fuel and new cladding to make them suitable for testing; S10: evacuating the reaction space and then purging the reaction space with high-purity inert gas; S20: placing the processed new fuel and new cladding together and placing them into the reaction space for testing; S30: introducing a protective gas into the reaction space to reach a first predetermined pressure; S40: heating the reaction space to a predetermined temperature and holding it at that temperature for a predetermined time; S50: adjusting the contact force between the new fuel and new cladding during the heating and holding phases; S60: removing the new fuel and new cladding from the reaction space and analyzing the microstructure of the new fuel and new cladding; S70: determining the compatibility between the new fuel and new cladding based on the analysis in step S60.

[0007] The experimental method in the embodiments of this application simulates the actual pressure and temperature inside the reactor, conducts compatibility tests on new fuel and new cladding under these conditions, and adjusts the contact force between the new fuel and new cladding during the heating and heat preservation stages to accurately simulate the interaction between fuel and cladding under actual operating conditions. This makes the reaction between the new fuel and new cladding closer to the actual situation, thereby improving the experimental accuracy and enhancing the accuracy and reliability of the experimental results obtained by analyzing the microstructure of the new fuel and new cladding. Attached Figure Description

[0008] Other objects and advantages of this application will become apparent from the following description of embodiments of this application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of this application.

[0009] Figure 1 This is a flowchart of a test method according to an embodiment of this application;

[0010] Figure 2 This is a schematic diagram of the structure of an experimental system according to an embodiment of this application.

[0011] Explanation of reference numerals in the attached figures:

[0012] 1. New fuel; 2. New casing; 10. Reaction module; 11. Reaction space; 20. Contact force control module; 21. Pressure bar; 22. Press; 23. Pressure measuring device.

[0013] It should be noted that the accompanying drawings are not necessarily drawn to scale, but are shown only in a schematic manner without affecting the reader's understanding. Detailed Implementation

[0014] Exemplary embodiments of this application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the development of any such actual embodiment to achieve the developer's specific goals, such as complying with constraints related to the system and business, and these constraints may vary depending on the implementation. Furthermore, it should be understood that while development work can be very complex and time-consuming, such development work is merely a routine task for those skilled in the art who benefit from the content of this application.

[0015] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the equipment structure and / or processing steps closely related to the solution according to this application are shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0016] The inventors of this application have discovered that there is currently no method for determining the compatibility between fuel and cladding that can accurately simulate the actual reaction conditions inside the reactor and the interaction between fuel and cladding under actual operating conditions. This results in poor experimental accuracy and affects the accuracy and reliability of the final experimental results.

[0017] Based on this, embodiments of this application provide a testing method suitable for determining the compatibility between new fuel and new cladding, such as... Figure 1 As shown, Figure 1 A flowchart illustrating a testing method according to an embodiment of this application is shown, the method comprising the following steps S10 to S70:

[0018] S00: Process new fuel and new cladding to make it suitable for testing.

[0019] S10: Evacuate the reaction space and then clean the reaction space with high-purity inert gas.

[0020] S20: Place the treated new fuel and new cladding together and put them into the reaction space where the test will be conducted.

[0021] S30: Introduce protective gas into the reaction space to reach the first predetermined pressure.

[0022] S40: Heat the reaction space to a predetermined temperature and maintain the temperature for a predetermined time.

[0023] S50: Adjust the contact force between the new fuel and the new cladding during the heating and heat preservation stages.

[0024] S60: Remove the new fuel and new cladding from the reaction space and analyze the microstructure of the new fuel and new cladding.

[0025] S70: Based on the analysis in step S60, determine the compatibility between the new fuel and the new cladding.

[0026] The method provided in the embodiments of this application simulates the actual pressure and temperature inside the reactor, conducts compatibility tests on new fuel and new cladding under these conditions, and adjusts the contact force between the new fuel and new cladding during the heating and heat preservation stages to accurately simulate the interaction between fuel and cladding under actual operating conditions. This makes the reaction between the new fuel and new cladding closer to the actual situation, thereby improving the test accuracy and enhancing the accuracy and reliability of the test results obtained by analyzing the microstructure of the new fuel and new cladding.

[0027] In some embodiments, in step S00, the new fuel and new cladding are processed to make them consistent with the fuel and cladding actually in service in the reactor, thereby accurately simulating the actual situation of the fuel elements in the reactor and further improving the accuracy and reliability of the test.

[0028] In some embodiments, in step S00, the new fuel is processed to make its surface roughness and porosity consistent with that of the fuel in service in the reactor; and the new cladding is preheated to change its microstructure to be consistent with that of the cladding in service in the reactor, so as to simulate the fuel and cladding actually in service in the reactor.

[0029] In step S20, when the treated new fuel and new cladding are placed into the reaction space for testing, multiple new fuels and multiple new claddings can be stacked to obtain multiple test data simultaneously under the same contact force conditions. The test results can then be obtained based on the multiple test data, thereby reducing errors and improving test accuracy.

[0030] Specifically, when multiple new fuels and multiple new claddings are stacked, one new fuel and one new cladding can be divided into a group to form multiple test groups. Multiple test groups are then stacked in the reaction space for testing, so that the same contact force acts on multiple test groups simultaneously, thereby obtaining multiple test data.

[0031] In some embodiments, in step S40, the first predetermined pressure is adjusted to a second predetermined pressure during the heat preservation process. The second predetermined pressure is greater than the first predetermined pressure to increase the reaction rate between the new fuel and the new cladding during the heat preservation process, ensuring that the two react fully, thereby improving the test accuracy and the reliability of the test results.

[0032] In some embodiments, step S50 further includes the following step:

[0033] S51: Obtain data on the changes in contact force between fuel and cladding under actual reactor operating conditions.

[0034] S52: Adjust the contact force between the new fuel and the new cladding based on the contact force change data obtained in step S51.

[0035] In this embodiment, data on the changes in contact force between fuel and cladding under actual reactor operating conditions are used to adjust the contact force between new fuel and new cladding during the experiment. This allows for a more accurate simulation of the interaction between fuel and cladding under actual operating conditions, thereby improving the accuracy and reliability of the experiment.

[0036] In some embodiments, in step S50, the temperature change of the reaction space under actual reactor operating conditions is obtained. During the adjustment of the contact force, the temperature in the reaction space is controlled in the same way as the change under actual reactor operating conditions. This is to further simulate the relationship between the actual reaction temperature of the reactor and the change of contact force between the fuel and the cladding in the experiment, so that the reaction between the new fuel and the new cladding is closer to the actual operating conditions and the test accuracy is improved.

[0037] In some embodiments, during step S50, the gas inside the new cladding can be replaced during the heating process. For example, the gas inside the cladding can be replaced with helium and trace oxygen to simulate the gas changes inside the cladding when the fuel element is in service in the reactor. This makes the reaction between the new fuel and the new cladding closer to the actual operating conditions, thereby improving the accuracy of the test.

[0038] In some embodiments, in step S00, new fuel and new casing are processed such that vent holes are provided on the new fuel and new casing respectively to facilitate the inflow and outflow of gas in the new casing, thereby facilitating the replacement of gas in the new casing in step S50.

[0039] In some embodiments, after the new fuel and new cladding are removed from the reaction space in step S60, the new fuel and new cladding are placed under a protective atmosphere to prevent the reaction layer from being damaged, which would affect the analysis results of the microstructure of the new fuel and new cladding and thus reduce the accuracy of the test.

[0040] In some embodiments, in step S60, during the analysis process, the new fuel and new cladding undergo non-destructive testing to prevent damage to the new fuel and new cladding, allowing them to be reused in new tests. This facilitates multiple tests on the same set of new fuel and new cladding, reducing errors caused by changing test materials, improving test accuracy, and simultaneously reducing the consumption of new fuel and new cladding, thereby improving resource utilization.

[0041] In some embodiments, in step S60, elemental scanning analysis and phase structure analysis are performed on the new fuel and the new cladding to determine the composition of the new cladding included in the new fuel and the composition of the new fuel included in the new cladding, as well as the influence of the composition of the new fuel on the new cladding and the influence of the composition of the new cladding on the new fuel, so as to determine the degree of interaction between the new fuel and the new cladding, thereby accurately determining the compatibility between the new fuel and the new cladding.

[0042] In step S70, based on the analysis results of step S60, when the content of the new fuel components included in the new cladding and the content of the new fuel components included in the new cladding are less than predetermined values, and the influence of the new fuel components on the new cladding and the influence of the new cladding components on the new fuel are less than predetermined values, the compatibility between the two is good; when the content of the new fuel components included in the new cladding and the content of the new fuel components included in the new cladding are greater than predetermined values, and the influence of the new fuel components on the new cladding and the influence of the new cladding components on the new fuel are greater than predetermined values, the compatibility between the two is poor.

[0043] In step S60, the weight changes before and after the new fuel and new cladding tests can be determined separately. In step S70, if the weight changes before and after the new fuel and new cladding tests are less than the predetermined values, the compatibility between the two is good; if the weight changes before and after the new fuel and new cladding tests are greater than the predetermined values, the compatibility between the two is poor.

[0044] Embodiments of this application also provide a testing system suitable for determining the compatibility between new fuel and new cladding, such as... Figure 2 As shown, Figure 2 The diagram illustrates the structure of a test system according to an embodiment of this application. The test system includes: a processing module configured to process new fuel and new cladding for testing; a reaction module 10 having a reaction space 11, into which the processed new fuel 1 and new cladding 2 are placed for testing; a protective gas supply module supplying protective gas to the reaction space 11 at a first predetermined pressure; a heating module configured to heat the reaction space 11 to a predetermined temperature; a contact force control module 20 configured to adjust the contact force between the new fuel 1 and the new cladding 2; and an analysis module configured to analyze the microstructure of the new fuel and new cladding, and determine the compatibility between the new fuel and new cladding based on the analysis results.

[0045] The system provided in the embodiments of this application can simulate the actual pressure and temperature inside a reactor, conduct compatibility tests on new fuel and new cladding under these conditions, and adjust the contact force between the new fuel and new cladding to accurately simulate the interaction between the fuel and cladding under actual operating conditions, making the reaction between the new fuel and new cladding closer to the actual situation, thereby improving the test accuracy and enhancing the accuracy and reliability of the test results obtained by analyzing the microstructure of the new fuel and new cladding.

[0046] The contact force control module 20 includes a pressure rod 21, a press 22, and a pressure measuring element 23. The pressure rod 21 is configured to provide pressure to the new fuel 1 and the new cladding 2 to change the contact force between the new fuel 1 and the new cladding 2. The press 22 is used to pressurize the pressure rod 21 so that the pressure rod 21 provides pressure to the new fuel 1 and the new cladding 2. The pressure measuring element 23 is configured to measure the pressure provided by the pressure rod 21 to the new fuel 1 and the new cladding 2 to determine the change in the contact force between the new fuel 1 and the new cladding 2.

[0047] The process of determining the compatibility between fuel and cladding in this application is further illustrated below with specific embodiments.

[0048] The process involves treating the new fuel to match the surface roughness and porosity of the fuel already in service in the reactor, preheating the new cladding to alter its microstructure and align it with that of the cladding used in the reactor, evacuating the reaction space, and then purging it with high-purity inert gas. Multiple test groups are formed by grouping the treated new fuel and the new cladding into a single unit, and these groups are then stacked within the test reaction space. A protective gas is introduced into the reaction space at 1-2 MPa. The reaction space is then heated, and during heating, the gas inside the new cladding is replaced based on changes in the gas content within the cladding during the fuel element's service life in the reactor. Once the reaction space temperature reaches 1100 K, it is held at that temperature for a predetermined time, during which time the reaction space is pressurized. Data on the changes in the contact force between the fuel and the cladding under actual reactor operating conditions is acquired, and based on this data, adjustments are made during the heating phase and... During the heat preservation stage, the contact force between the new fuel and the new cladding is adjusted within the range of 1N to 10N. The new fuel and the new cladding are then removed from the reaction space, and elemental scanning analysis and phase structure analysis are performed on their microstructures under a protective atmosphere to determine the components of the new cladding included in the new fuel, the components of the new fuel included in the new cladding, and the influence of the components of the new fuel on the new cladding, and the influence of the components of the new cladding on the new fuel. When the contents of the components of the new cladding included in the new fuel and the new fuel included in the new cladding are less than predetermined values, and the influence of the components of the new fuel on the new cladding and the influence of the components of the new cladding on the new fuel are also less than predetermined values, the compatibility between the two is good. When the contents of the components of the new cladding included in the new fuel and the new fuel included in the new cladding are greater than predetermined values, and the influence of the components of the new fuel on the new cladding and the influence of the components of the new cladding on the new fuel are also greater than predetermined values, the compatibility between the two is poor.

[0049] Regarding the embodiments of this application, it should also be noted that, without conflict, the embodiments of this application and the features in the embodiments can be combined with each other to obtain new embodiments.

[0050] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A test method suitable for determining the compatibility between new fuel and new cladding, characterized in that, It includes the following steps: S00: Process the new fuel and the new cladding to make them suitable for the test; S10: Evacuate the reaction space and then clean the reaction space with high-purity inert gas; S20: Place the treated new fuel and the new cladding together and put them into the reaction space for the test; S30: Introduce protective gas into the reaction space to reach a first predetermined pressure; S40: Heat the reaction space to a predetermined temperature and maintain the temperature for a predetermined time; S50: During the heating and heat preservation stages, adjust the contact force between the new fuel and the new cladding; S60: Remove the new fuel and the new coating from the reaction space and analyze the microstructure of the new fuel and the new coating; S70: Based on the analysis in step S60, determine the compatibility between the new fuel and the new cladding; In step S40, during the heat preservation process, the first predetermined pressure is adjusted to a second predetermined pressure, where the second predetermined pressure is greater than the first predetermined pressure. The S50 step also includes the following steps: S51: Obtain data on the changes in contact force between fuel and cladding under actual reactor operating conditions; S52: Adjust the contact force between the new fuel and the new cladding based on the contact force change data obtained in step S51; In step S60, during the analysis process, the new fuel and the new cladding undergo non-destructive testing to ensure that the new fuel and the new cladding are not damaged and can be reused for new tests.

2. The test method according to claim 1, characterized in that, In step S00, the new fuel and the new cladding are processed to make them consistent with the fuel and cladding actually in service in the reactor.

3. The test method according to claim 2, characterized in that, In step S00, the new fuel is processed to make its surface roughness and porosity consistent with those of the fuel already in service in the reactor. In step S00, the new cladding is preheated to change its microstructure so that it is consistent with the cladding already in service in the reactor.

4. The test method according to claim 1, characterized in that, In step S50, the temperature change of the reaction space under actual reactor operating conditions is obtained, and during the adjustment of the contact force, the temperature in the reaction space is controlled in the same way as the temperature change under actual reactor operating conditions.

5. The test method according to claim 1, characterized in that, In step S50, the gas inside the new casing can be replaced during the heating process.

6. The test method according to claim 5, characterized in that, In step S00, the new fuel and the new cladding are processed such that pores are provided on the new fuel and the new cladding respectively.

7. The test method according to claim 1, characterized in that, In step S60, after the new fuel and the new cladding are removed from the reaction space, the new fuel and the new cladding are placed under a protective atmosphere to prevent the reaction layer from being damaged.

8. The test method according to claim 1, characterized in that, In step S60, elemental scanning analysis and phase structure analysis are performed on the new fuel and the new cladding to determine the composition of the new cladding included in the new fuel and the composition of the new fuel included in the new cladding, as well as the influence of the composition of the new fuel on the new cladding and the influence of the composition of the new cladding on the new fuel.

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