Method and system for synchronously testing residual stress and hydrogen content

Abstract

The invention provides a method and a system for synchronously testing residual stress and hydrogen content. The method comprises the following steps: determining components and crystal structure types of a to-be-tested material; detecting the texture of the to-be-detected material; determining test crystal faces in three directions of the residual stress of the neutron diffraction detection sample, and testing lattice strain in the three directions; carrying out a prompt gamma experiment by using the standard sample to obtain a standard sample activation energy spectrum of neutron-activated prompt gamma; determining a series of to-be-tested positions for synchronously testing the residual stress and the hydrogen content, and further determining a sample table movement parameter corresponding to each measurement position; acquiring neutron diffraction data, testing lattice strain in three directions, and acquiring a signal of instant gamma at the same time; and constructing position corresponding information of neutron diffraction test and neutron activation instant gamma test data, and performing data processing to obtain final residual stress distribution and hydrogen content distribution. According to the detection method, the internal residual stress and the hydrogen content of the material can be simultaneously tested by utilizing a primary neutron diffraction experiment.

Description

Technical Field

[0001] The present invention relates to the technical field of neutron diffraction testing of residual stress, and specifically, to a method and system for synchronously testing residual stress and hydrogen content. Background Art

[0002] The residual stress inside a material can affect the mechanical properties of the material, including strength and plasticity; in addition, the enrichment of hydrogen elements inside the material can also affect plastic deformation and crack propagation behavior. There are some connections between the residual stress distribution and the hydrogen element concentration distribution inside the material. Clarifying the mutual influence between the two is of great significance for studying the mechanical failure of materials. However, the existing technologies can only measure the residual stress and the hydrogen concentration distribution separately, and cannot measure both simultaneously. On the one hand, the measurement results of the residual stress and the hydrogen concentration lose the temporal synchronization; on the other hand, due to the separate measurement, there may be some deviations in the measurement positions, resulting in spatial deviations. In order to maintain the spatio-temporal synchronization of the two variables, a method for synchronously testing multiple parameters of residual stress-hydrogen concentration is needed.

[0003] In the existing related technologies, a method for measuring residual stress by neutron diffraction technology was published on pages 445-473 of the journal Advances in Physics in August 1985; a method for testing three-dimensional stress by the grain orientation method was published on pages 499-509 of the journal Acta Materialia in January 2010; a Chinese patent with the application number CN201810275227.5 disclosed a method for testing the residual stress of thick plates by neutron diffraction technology; a Chinese patent with the application number CN201110276888.8 disclosed a device and method for measuring residual stress by neutron diffraction; and a Chinese patent with the application number CN201810450457.0 disclosed a device and method for measuring the element distribution of a sample based on prompt gamma-ray neutron activation analysis technology; the methods mentioned in these existing technologies are all for the development of independent testing methods. The two neutron source-based technologies are not combined to achieve the synchronous testing of two parameters, namely residual stress and hydrogen concentration. Summary of the Invention

[0004] In view of the defects in the existing technology, the present invention provides a method and system for synchronously testing residual stress and hydrogen content.

[0005] According to a method and system for synchronously testing residual stress and hydrogen content provided by the present invention, the scheme is as follows:

[0006] In the first aspect, a method for synchronously testing residual stress and hydrogen content is provided, and the method includes:

[0007] Step S1: Determine the composition and crystal structure type of the material to be tested;

[0008] Step S2: Detect the texture of the material to be measured;

[0009] Step S3: Determine the test crystal planes in the x, y, and z directions for detecting the residual stress of the neutron diffraction test sample, and measure the lattice strain in the x, y, and z directions;

[0010] Step S4: Use a standard sample to conduct a prompt gamma experiment to obtain the activation energy spectrum of the prompt gamma of neutron activation;

[0011] Step S5: Determine a series of positions to be measured for the synchronous measurement of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position;

[0012] Step S6: Collect neutron diffraction data, measure the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma;

[0013] Step S7: Construct the position correspondence information of the neutron diffraction test and the neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution.

[0014] Preferably, the step S5 includes:

[0015] Step S5.1: Fix the sample on the sample stage, and determine the test positions inside the sample according to the test requirements; Place a copper foil in front of the sample, and calibrate the prompt gamma result with the characteristic peak of its neutron activation prompt gamma;

[0016] Step S5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be measured, and establish the correspondence between the movement information of the sample stage and the sample measurement position.

[0017] Preferably, the step S6 includes:

[0018] Step S6.1: Move the sample to the corresponding position according to the movement parameters of the sample stage corresponding to each measurement position, and rotate the Euler ring to the lattice strain test direction;

[0019] Step S6.2: Determine the lattice plane spacing d to be measured according to the lattice planes hkl to be measured in three directions (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) = nλ to calculate the diffraction angle 2θ (hkl) , and move the detector to the specified 2θ (hkl) angle;

[0020] Step S6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal;

[0021] Step S6.4: Collect neutron activation prompt gamma signals while collecting neutron diffraction signals;

[0022] Step S6.5: Repeat steps S6.1 to S6.3 until the neutron diffraction test signal collection is completed for all three test directions of lattice strain.

[0023] Preferably, the said step S7 includes:

[0024] Step S7.1: Read the neutron diffraction signals and neutron activation prompt gamma signals obtained from neutron diffraction tests and neutron activation prompt gamma tests. According to the sample stage movement parameters in the original data and the corresponding relationship between the movement information of the sample stage and the sample measurement position established in step S5.2, clarify the test position information corresponding to the neutron diffraction test and neutron activation prompt gamma test results;

[0025] Step S7.2: Analyze the neutron diffraction test results and calculate the residual stress at the test position; Fit the neutron diffraction data in the three collected directions to obtain the diffraction angle 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strains ε x , ε y , ε z in the x, y, and z directions in the three directions according to the change of the diffraction angle:

[0026]

[0027] Then, according to the strains in the three directions and the elastic constant E and Poisson's ratio v of the material to be measured, combined with Hooke's law, the residual strains σ x , σ y , σ z in the three directions at the test position can be calculated:

[0028]

[0029] Step S7.3: Analyze the neutron activation prompt gamma results and calculate the hydrogen content at the test position; Perform energy calibration and relative efficiency scale calibration according to the activation energy spectrum of the standard sample tested in step S4. Use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum. Analyze the collected neutron activation prompt gamma signals to obtain the area count of each activation peak, divide by the test time to obtain the counting rate, and obtain the hydrogen content at the detection position by comparing the gamma activation peak of hydrogen element and the activation peak of the main element of the sample;

[0030] Step S7.4: Repeat steps S7.1 to S7.3 for all detection positions, and then the residual stress and hydrogen content at all detection positions can be determined, thereby establishing the distribution of residual stress and hydrogen content.

[0031] In a second aspect, a system for synchronously measuring residual stress and hydrogen content is provided. The system includes:

[0032] Module M1: Determine the composition and crystal structure type of the material to be measured.

[0033] Module M2: Detect the texture of the material to be measured.

[0034] Module M3: Determine the test crystal planes in the x, y, and z directions for detecting the residual stress of the neutron diffraction sample, and measure the lattice strain in the x, y, and z directions.

[0035] Module M4: Use a standard sample to perform a prompt gamma experiment to obtain the activation energy spectrum of the neutron activation prompt gamma of the standard sample.

[0036] Module M5: Determine a series of positions to be measured for the synchronous measurement of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position.

[0037] Module M6: Collect neutron diffraction data, measure the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma.

[0038] Module M7: Construct the position correspondence information of the neutron diffraction test and the neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution.

[0039] Preferably, the module M5 includes:

[0040] Module M5.1: Fix the sample on the sample stage, and determine the test positions inside the sample according to the test requirements; place a copper foil in front of the sample, and calibrate the prompt gamma result with the characteristic peak of its neutron activation prompt gamma.

[0041] Module M5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be measured, and establish the correspondence between the movement information of the sample stage and the sample measurement position.

[0042] Preferably, the module M6 includes:

[0043] Module M6.1: Move the sample to the corresponding position according to the movement parameters of the sample stage corresponding to each measurement position, and rotate the Euler ring to the lattice strain measurement direction.

[0044] Module M6.2: Determine the lattice plane spacing d to be measured according to the lattice planes hkl to be measured in three directions (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) = nλ to calculate the diffraction angle 2θ (hkl) , and move the detector to the specified 2θ(hkl) Angle;

[0045] Module M6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal;

[0046] Module M6.4: Collect the neutron activation prompt gamma signal while collecting the neutron diffraction signal;

[0047] Module M6.5: Repeat Modules M6.1 to M6.3 until the neutron diffraction test signals are all collected for the three test directions of the lattice strain.

[0048] Preferably, the Module M7 includes:

[0049] Module M7.1: Read the neutron diffraction signal and the neutron activation prompt gamma signal obtained from the neutron diffraction test and the neutron activation prompt gamma test, and according to the sample stage movement parameters in the original data and the correspondence between the movement information of the sample stage and the sample measurement position established by Module M5.2, clarify the test position information corresponding to the neutron diffraction test and the neutron activation prompt gamma test results;

[0050] Module M7.2: Analyze the neutron diffraction test results and calculate the residual stress at the test position; perform fitting on the neutron diffraction data in the three collected directions to obtain the diffraction angle 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strains ε x , ε y , ε z in the x, y, and z directions in the three directions according to the change of the diffraction angle:

[0051]

[0052]

[0053] Then, according to the strains in the three directions and the elastic constant E and Poisson's ratio v of the material to be measured, combined with Hooke's law, the residual strains σ x , σ y , σ z in the three directions at the test position can be calculated:

[0054]

[0055] Module M7.3: Analyze the prompt gamma results of neutron activation, calculate the hydrogen content at the test position; perform energy calibration and relative efficiency calibration according to the activation energy spectrum of the standard sample tested in step S4, use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum, analyze the collected prompt gamma signals of neutron activation, obtain the area counts of each activation peak, divide by the test time to get the counting rate, and obtain the hydrogen content at the detection position by comparing the gamma activation peak of the hydrogen element with the activation peak of the main element of the sample;

[0056] Module M7.4: Repeat Modules M7.1 to M7.3 for all detection positions, that is, the residual stress and hydrogen content at all detection positions can be determined, thereby establishing the distribution of residual stress and hydrogen content.

[0057] Compared with the prior art, the present invention has the following beneficial effects:

[0058] By combining the neutron diffraction technique that can originally only be used to test the residual stress of materials and the neutron activation prompt Gamma technique that can only be used to test the hydrogen concentration of materials, the present invention finally realizes a detection method for simultaneously testing the internal residual stress and hydrogen content of materials using a single neutron diffraction experiment, thereby solving the problem of synchronous testing of residual stress and element content, and providing effective technical guidance for synchronous testing of the residual stress and hydrogen content distribution of specimens such as zirconium alloy pressure pipes in nuclear power plants.

[0059] Other beneficial effects of the present invention will be elaborated in the specific implementation manner through the introduction of specific technical features and technical solutions. Those skilled in the art should be able to understand the beneficial technical effects brought by the said technical features and technical solutions through these introductions. Description of the Drawings

[0060] By reading the following detailed description of the non-restrictive embodiments with reference to the accompanying drawings, other features, objectives, and advantages of the present invention will become more apparent:

[0061] Figure 1 It is a schematic diagram of the overall process of the present invention. Specific Embodiment

[0062] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0063] The embodiment of the present invention provides a method for synchronous testing of residual stress and hydrogen content, combining neutron diffraction technology and neutron activation prompt Gamma technology, with reference toFigure 1 As shown, the method includes:

[0064] Step S1: Determine the composition and crystal structure type of the material to be tested. Determine whether the material to be tested is a single-phase or multi-phase material and the crystal structure type of each phase, and then determine the crystal planes available for testing the material to be tested by neutron diffraction and the existing elements for neutron activation prompt gamma detection.

[0065] Step S2: Detect the texture of the material to be tested. To measure the residual stress inside the material to be tested, specific diffraction crystal planes (hkl) need to be selected. Relying on the texture information of the material to be tested, the texture of the material can be detected according to the national standard "Neutron Testing Method for Texture of Nondestructive Testing Materials" (GB / T 40307-2021).

[0066] Step S3: Since measuring residual stress requires measuring the lattice strain in three mutually perpendicular directions (denoted as the x, y, and z directions), it is necessary to determine the test crystal planes in the three directions for neutron diffraction detection of the sample's residual stress. The test crystal planes of the material to be detected can be determined according to the texture information of the material to be tested and in combination with the national standard "Neutron Diffraction Method for Measuring Residual Stress of Nondestructive Testing" (GB / T 26140-2023).

[0067] Step S4: Use a standard sample to conduct a prompt gamma experiment to obtain the activation energy spectrum of the neutron activation prompt gamma of the standard sample.

[0068] Step S5: Determine a series of positions to be tested for synchronous measurement of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position. This step S5 specifically includes:

[0069] Step S5.1: Fix the sample on the sample stage, and determine the test positions inside the sample according to the test requirements (the test requirements specifically refer to what positions of the hydrogen concentration the tester is concerned about, as well as the test priority, test time, etc. For example, to test the hydrogen concentration distribution inside the zirconium alloy tube of the nuclear fuel cladding, it is necessary to determine the characteristic positions where the hydrogen concentration may vary according to the initial conditions such as the processing technology and residual stress of the material, as well as the service conditions during subsequent use, including whether there is a load, service temperature, service environment, etc., and then determine the specific test positions according to the test time and priority); place a copper foil in front of the sample, and calibrate the prompt gamma results with the characteristic peak of its neutron activation prompt gamma (neutron activation prompt gamma analysis is to bombard the isotopes of elements in the sample with neutrons to generate nuclear reactions, and perform qualitative and quantitative analysis of the elements in the substance by measuring the ray energy and intensity of the generated prompt gamma. The characteristic energy of the gamma rays generated by a specific element (such as copper element here) under the bombardment of neutrons with a specific energy is fixed. Therefore, only the characteristic energy of the gamma rays generated by the copper element in the database needs to be compared with the energy spectrum generated in the experiment to determine information such as the neutron energy, and calibrate the energy spectrum of the element to be tested in the sample).

[0070] Step S5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be tested, and establish the corresponding relationship between the movement information of the sample stage and the sample measurement position.

[0071] Among them, to determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be tested, the relative position of the sample with respect to the sample stage is determined through information such as the placement position and placement direction of the sample on the sample stage. According to the relative position of the two, the relative displacement of moving the position to be tested of the sample (assumed to be sample position A) to the test center of the sample stage is determined. The movement parameters of the sample stage are finally determined according to this relative displacement.

[0072] Establish the corresponding relationship between the movement information of the sample stage and the sample measurement position. After the sample stage moves through the movement parameters, the test position of the corresponding sample will be moved to the test center of the sample stage. Therefore, it can be determined that the corresponding position during the test is the position to be tested A of the sample. Therefore, the relationship between this position A and the corresponding displacement parameter can be established.

[0073] Step S6: Collect neutron diffraction data, test the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma. This step S6 specifically includes:

[0074] Step S6.1: According to the movement parameters of the sample stage corresponding to each measurement position, move the sample to the corresponding position, and rotate the Euler ring to the lattice strain test direction;

[0075] Step S6.2: Determine the lattice plane spacing d to be measured according to the lattice planes (hkl) to be measured in the three directions determined in Step S3 (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) = nλ to calculate the diffraction angle 2θ (hkl) , and move the detector to the specified 2θ (hkl) angle; where n is an integer multiple of the wavelength, and the diffraction angle 2θ is the angle between the forward direction of the diffracted neutrons and the forward direction of the incident neutrons after neutron diffraction occurs

[0076] Step S6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal

[0077] Specifically, when performing neutron diffraction, in addition to the diffracted neutrons hitting the detector to generate a signal, the background neutrons hitting the detector will also generate a signal. Therefore, sufficient test time is required to make the diffraction signal strong enough compared to the background signal. The ratio of the diffraction signal to the background signal is the signal-to-noise ratio here. Different materials and different samples generate different diffraction signal intensities. Therefore, different test times or neutron counts need to be selected for different materials

[0078] Step S6.4: Collect the prompt gamma signal of neutron activation while collecting the neutron diffraction signal (collect the prompt gamma rays through a specific detector)

[0079] Step S6.5: Repeat Steps S6.1 to S6.3 until the neutron diffraction test signal collection for all three lattice strain test directions is completed

[0080] Step S7: Construct the position correspondence information of the neutron diffraction test and the neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution. This Step S7 specifically includes

[0081] Step S7.1: Read the neutron diffraction signal and the prompt gamma signal of neutron activation obtained from the neutron diffraction test and the neutron activation prompt gamma test, and according to the sample stage movement parameters in the original data and the correspondence relationship between the movement information of the sample stage and the sample measurement position established in Step S5.2, clarify the test position information corresponding to the neutron diffraction test and the neutron activation prompt gamma test results

[0082] Step S7.2: Analyze the neutron diffraction test results and calculate the residual stress at the test position; perform fitting on the neutron diffraction data in the three collected directions to obtain the diffraction angles 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strain ε in the three directions (x, y, z) from the change in the diffraction anglex , ε y , ε z :

[0083]

[0084] Based on the strains in three directions and the elastic constants E and Poisson's ratio v of the material to be measured, combined with Hooke's law, the residual strains σ in three directions at the test position can be calculated. x , σ y , σ z :

[0085]

[0086] Step S7.3: Analyze the results of neutron activation prompt gamma, and calculate the hydrogen content at the test position; perform energy calibration and relative efficiency scale calibration according to the activation energy spectrum of the standard sample tested in step S4, and use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum. Use Genie2000 software to analyze the neutron activation prompt gamma signals collected in step S6.4 to obtain the area counts of each activation peak, divide by the test time to obtain the counting rate, and obtain the hydrogen content at the detection position by comparing the gamma activation peak of hydrogen element with the activation peak of the main element of the sample.

[0087] Step S7.4: Repeat steps S7.1 to S7.3 for all detection positions, and the residual stress and hydrogen content at all detection positions can be determined, thereby establishing the distribution of residual stress and hydrogen content.

[0088] The present invention also provides a synchronous testing system for residual stress and hydrogen content. The synchronous testing system for residual stress and hydrogen content can be realized by executing the process steps of the synchronous testing method for residual stress and hydrogen content. That is, those skilled in the art can understand the synchronous testing method for residual stress and hydrogen content as the preferred implementation manner of the synchronous testing system for residual stress and hydrogen content. The system specifically includes:

[0089] Module M1: Determine the composition and crystal structure type of the material to be measured. Determine whether the material to be measured is a single-phase or multi-phase material and the crystal structure type of each phase, and then determine the crystal planes available for testing the material by neutron diffraction and the existing elements for neutron activation-prompt Gamma detection.

[0090] Module M2: Detect the texture of the material to be measured. The selection of specific diffraction crystal planes (hkl) is required for the residual stress inside the material to be measured. Relying on the texture information of the material to be measured, the texture of the material can be detected according to the national standard "Neutron Testing Method for Texture of Nondestructive Testing Materials" (GB / T40307-2021).

[0091] Module M3: Since it is necessary to measure the lattice strain in three mutually perpendicular directions (denoted as the x, y, and z directions) for testing residual stress, it is necessary to determine the test crystal planes in the three directions for neutron diffraction detection of the sample residual stress. The test crystal planes of the material to be detected can be determined according to the texture information of the material to be measured and in combination with the national standard "Neutron Diffraction Method for Measuring Residual Stress in Non-destructive Testing" (GB / T 26140-2023).

[0092] Module M4: Use a standard sample to conduct a prompt gamma experiment to obtain the activation energy spectrum of the standard sample for neutron activation prompt gamma.

[0093] Module M5: Determine a series of positions to be measured for synchronous testing of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position. This module M5 specifically includes:

[0094] Module M5.1: Fix the sample on the sample stage and determine the test positions inside the sample according to the test requirements; place a copper foil in front of the sample and calibrate the prompt gamma results with the characteristic peak of its neutron activation prompt gamma;

[0095] Module M5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be measured, and establish the corresponding relationship between the movement information of the sample stage and the sample measurement position.

[0096] Module M6: Collect neutron diffraction data, measure the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma. This module M6 specifically includes:

[0097] Module M6.1: Move the sample to the corresponding position according to the sample stage movement parameters corresponding to each measurement position, and rotate the Euler ring to the lattice strain test direction;

[0098] Module M6.2: Determine the lattice plane spacing d to be measured according to the lattice planes (hkl) to be measured in three directions (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) =nλ to calculate the diffraction angle 2θ (hkl) , move the detector to the specified 2θ (hkl) angle;

[0099] Module M6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal;

[0100] Module M6.4: Collect the neutron activation prompt gamma signal while collecting the neutron diffraction signal;

[0101] Module M6.5: Repeat Modules M6.1 to M6.3 until the neutron diffraction test signal collection for all three lattice strain test directions is completed.

[0102] Module M7: Construct the position correspondence information of neutron diffraction test and neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution.

[0103] This module M7 specifically includes:

[0104] Module M7.1: Read the neutron diffraction signal and neutron activation prompt gamma signal obtained from the neutron diffraction test and neutron activation prompt gamma test. According to the sample stage movement parameters in the original data and the correspondence relationship between the movement information of the sample stage and the sample measurement position established by module M5.2, clarify the test position information corresponding to the neutron diffraction test and neutron activation prompt gamma test results;

[0105] Module M7.2: Analyze the neutron diffraction test results and calculate the residual stress at the test position; Fit the neutron diffraction data in three directions to obtain the diffraction angle 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strain ε x , ε y , ε z in three directions (x, y, z) according to the change of the diffraction angle:

[0106]

[0107] Then, according to the strain in three directions and the elastic constants E and Poisson's ratio v of the material to be measured, combined with Hooke's law, the residual strain σ x , σ y , σ z in three directions at the test position can be calculated:

[0108]

[0109] Module M7.3: Analyze the neutron activation prompt gamma results and calculate the hydrogen content at the test position; Perform energy calibration and relative efficiency scale calibration according to the activation energy spectrum of the standard sample tested by module M4, and use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum. Use Genie2000 software to analyze the neutron activation prompt gamma signal collected by module M6.4 to obtain the area count of each activation peak, divide by the test time to obtain the count rate, and obtain the hydrogen content at the detection position by comparing the gamma activation peak of hydrogen element and the activation peak of the main element of the sample.

[0110] Module M7.4: Repeat modules M7.1 to M7.3 for all detection positions, and the residual stress and hydrogen content of all detection positions can be determined, thus establishing the residual stress and hydrogen content distribution.

[0111] An embodiment of the present invention provides a method and system for synchronously measuring residual stress and hydrogen content. By combining neutron diffraction technology and neutron activation prompt gamma technology, while measuring residual stress through neutron diffraction technology, the measurement of hydrogen concentration by neutron activation prompt gamma technology is completed. Thus, a multi-parameter synchronous measurement method for residual stress - hydrogen content is established, and multi-parameter measurement can be synchronously completed through one neutron experiment, ensuring the consistency of measurement results in terms of time and space. Thereby, the problem of synchronous measurement of residual stress and element content is solved.

[0112] Those skilled in the art know that in addition to implementing the system and its various devices, modules, and units provided by the present invention in the form of pure computer-readable program code, the method steps can be logically programmed to enable the system and its various devices, modules, and units provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers, etc., to achieve the same functions. Therefore, the system and its various devices, modules, and units provided by the present invention can be regarded as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be regarded as the structure within the hardware component; the devices, modules, and units for implementing various functions can also be regarded as either software modules for implementing the method or the structure within the hardware component.

[0113] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other.

Claims

1. A method for synchronously measuring residual stress and hydrogen content, characterized in that, including: Step S1: Determine the composition and crystal structure type of the material to be measured; Step S2: Detect the texture of the material to be measured; Step S3: Determine the test crystal planes in the x, y, and z directions for detecting the residual stress of the neutron diffraction test sample, and measure the lattice strain in the x, y, and z directions; Step S4: Use a standard sample to conduct a prompt gamma experiment to obtain the activation energy spectrum of the neutron activation prompt gamma of the standard sample; Step S5: Determine a series of positions to be measured for synchronous testing of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position; Step S6: Collect neutron diffraction data, measure the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma; Step S7: Construct the position correspondence information of the neutron diffraction test and the neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution.

2. The synchronous testing method for residual stress and hydrogen content according to claim 1, characterized in that The said Step S5 includes: Step S5.1: Fix the sample on the sample stage, and determine the test positions inside the sample according to the test requirements; Place a copper foil in front of the sample to calibrate the prompt gamma result with the characteristic peak of its neutron activation prompt gamma; Step S5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be measured, and establish the correspondence between the movement information of the sample stage and the sample measurement position.

3. The method for synchronously measuring residual stress and hydrogen content according to claim 1, characterized in that, The said Step S6 includes: Step S6.1: According to the movement parameters of the sample stage corresponding to each measurement position, move the sample to the corresponding position, and rotate the Euler ring to the lattice strain measurement direction; Step S6.2: Determine the lattice plane spacing d to be measured according to the lattice planes hkl to be measured in three directions (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) = nλ to calculate the diffraction angle 2θ (hkl) , and move the detector to the specified 2θ (hkl) angle; Step S6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal; Step S6.4: Collect the neutron activation prompt gamma signal while collecting the neutron diffraction signal; Step S6.5: Repeat Steps S6.1 to S6.3 until the neutron diffraction test signal collection is completed for all three lattice strain measurement directions.

4. The synchronous testing method for residual stress and hydrogen content according to claim 2, characterized in that The said Step S7 includes: Step S7.1: Read the neutron diffraction signal and the neutron activation prompt gamma signal obtained from the neutron diffraction test and the neutron activation prompt gamma test. According to the movement parameters of the sample stage in the original data and the correspondence between the movement information of the sample stage and the sample measurement position established in Step S5.2, clarify the test position information corresponding to the neutron diffraction test and the neutron activation prompt gamma test results; Step S7.2: Analyze the neutron diffraction test results and calculate the residual stress at the test position; Fit the neutron diffraction data in three directions collected to obtain the diffraction angle 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strains ε x , ε y , ε z : According to the strains in three directions and the elastic constants E and Poisson's ratio ν of the material to be measured, combined with Hooke's law, the residual strains σ in three directions at the test position can be calculated. x , σ y , σ z : Step S7.3: Analyze the neutron activation prompt gamma result and calculate the hydrogen content of the test position; Step S7.4: Repeat Steps S7.1 to S7.3 for all detection positions, and then the residual stress and hydrogen content of all detection positions can be determined, thereby establishing the residual stress and hydrogen content distribution.

5. The synchronous testing method for residual stress and hydrogen content according to claim 4, characterized in that, The said Step S7.3 includes: Perform energy calibration and relative efficiency scale calibration according to the activation energy spectrum of the tested standard sample, use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum, analyze the collected neutron activation prompt gamma signal, obtain the area count of each activation peak, divide by the test time to obtain the count rate, and obtain the hydrogen content of the detection position through the comparison between the gamma activation peak of hydrogen element and the activation peak of the main element of the sample.

6. A synchronous testing system for residual stress and hydrogen content, characterized in that, including: Module M1: Determine the composition and crystal structure type of the material to be tested; Module M2: Detect the texture of the material to be tested; Module M3: Determine the test crystal planes in the x, y, and z directions for residual stress detection of the neutron diffraction sample, and measure the lattice strain in the x, y, and z directions; Module M4: Use a standard sample to conduct a prompt gamma experiment to obtain the activation energy spectrum of the neutron activation prompt gamma of the standard sample; Module M5: Determine a series of positions to be tested for simultaneous measurement of residual stress and hydrogen content, and then determine the sample stage movement parameters corresponding to each measurement position; Module M6: Collect neutron diffraction data, measure the lattice strain in three directions, and simultaneously collect the energy spectrum signal of prompt gamma; Module M7: Construct the position correspondence information of the neutron diffraction test and the neutron activation prompt gamma test data, and perform data processing to obtain the final residual stress distribution and hydrogen content distribution.

7. The residual stress and hydrogen content synchronous testing system according to claim 6, characterized in that The said Module M5 includes: Module M5.1: Fix the sample on the sample stage, and determine the test positions inside the sample according to the test requirements; Place a copper foil in front of the sample to calibrate the prompt gamma result with the characteristic peak of its neutron activation prompt gamma; Module M5.2: Determine the movement parameters of the sample stage when the incident neutrons irradiate the position to be tested, and establish the correspondence between the movement information of the sample stage and the sample measurement position.

8. The residual stress and hydrogen content synchronous testing system according to claim 6, characterized in that, The said Module M6 includes: Module M6.1: Move the sample to the corresponding position according to the movement parameters of the sample stage corresponding to each measurement position, and rotate the Euler ring to the lattice strain measurement direction; Module M6.2: Determine the lattice plane spacing d to be measured according to the lattice planes hkl to be measured in three directions (hkl) and the incident neutron wavelength λ, and use Bragg's diffraction law 2d (hkl) sinθ (hkl) = nλ to calculate the diffraction angle 2θ (hkl) , move the detector to the specified 2θ (hkl) angle; Module M6.3: Set the measurement duration or neutron count according to the signal-to-noise ratio requirement, and detect the neutron diffraction signal; Module M6.4: Collect the neutron activation prompt gamma signal while collecting the neutron diffraction signal; Module M6.5: Repeat Modules M6.1 - M6.3 until the neutron diffraction test signal collection for all three lattice strain measurement directions is completed.

9. The residual stress and hydrogen content synchronous testing system according to claim 7, characterized in that, The said Module M7 includes: Module M7.1: Read the neutron diffraction signal and the neutron activation prompt gamma signal obtained from the neutron diffraction test and the neutron activation prompt gamma test. According to the sample stage movement parameters in the original data and the correspondence between the movement information of the sample stage and the sample measurement position established in Module M5.2, clarify the test position information corresponding to the neutron diffraction test and the neutron activation prompt gamma test results; Module M7.2: Analyze the results of neutron diffraction tests, calculate the residual stress at the test positions; fit the neutron diffraction data in three directions collected to obtain the diffraction angle 2θ (hkl),x , 2θ (hkl),y and 2θ (hkl),z ; Obtain the strains ε x , ε y , ε z : Based on the strains in three directions and the elastic constants E and Poisson's ratio v of the material to be measured, combined with Hooke's law, the residual strains σ in three directions at the test position can be calculated. x , σ y , σ z : Module M7.3: Analyze the neutron activation prompt gamma result and calculate the hydrogen content at the test position; Module M7.4: Repeat Modules M7.1 - M7.3 for all detection positions, that is, the residual stress and hydrogen content at all detection positions can be determined, thereby establishing the residual stress and hydrogen content distribution.

10. The residual stress and hydrogen content synchronous testing system according to claim 9, characterized in that, The said Module M7.3 includes: Perform energy calibration and relative efficiency scale calibration according to the activation energy spectrum of the tested standard sample, use the activation characteristic peak of the copper foil to monitor the error and normalize the neutron activation energy spectrum, analyze the collected neutron activation prompt gamma signal, obtain the area count of each activation peak, divide by the test time to get the count rate, and obtain the hydrogen content at the detection position by comparing the gamma activation peak of hydrogen element and the activation peak of the main element of the sample.

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