Method and system for processing two-dimensional diffraction data of a biphasic single crystal material

Abstract

The application provides a two-dimensional diffraction data processing method and system of a two-phase single crystal material, is applied to neutron / X-ray diffraction two-dimensional surface detector data analysis of the two-phase single crystal material, each point diffraction intensity and direction information in the detector are extracted pixel by pixel, and one-dimensional rocking curves obtained by integrating along the eta direction are used to separate two-dimensional diffraction data corresponding to each subgrain, and finally two-dimensional diffraction data are fitted by using two-dimensional double Gaussian functions, and the crystal plane spacing and orientation information of the two phases in the subgrain are quantitatively analyzed. The application solves the problem of difficult peak separation caused by the overlapping of two-dimensional diffraction signals caused by subgrains and two-phase structures.

Description

Technical Field

[0001] This invention relates to the field of two-dimensional diffraction data processing technology, and more specifically, to a method and system for processing two-dimensional diffraction data of a dual-phase single-crystal material. Background Technology

[0002] Currently, existing software methods for processing diffraction data mainly analyze the microstructure of samples by compressing two-dimensional diffraction data to obtain one-dimensional diffraction curves and rocking curves. However, the compression of two-dimensional data leads to information loss, which is not conducive to the quantitative characterization and analysis of the interplanar spacing and orientation of materials with complex microstructures, such as two-phase single-crystal materials.

[0003] Patent document CN114972287A (application number: CN202210655117.8) discloses a two-dimensional X-ray diffraction data processing method and system, relating to the field of X-ray technology. The method includes: determining the position of a target pixel corresponding to a sample to be tested; the target pixel position is the position of the pixel covered by the diffraction ring, diffraction point, or diffraction arc corresponding to the target diffraction peak of the sample to be tested in the two-dimensional X-ray diffraction pattern; the target diffraction peak is the diffraction peak of the target component in the sample to be tested in the two-dimensional X-ray diffraction pattern; the target component is the component to be measured; based on the acquired two-dimensional X-ray diffraction pattern of the sample to be tested and the position of the target pixel, determining the diffraction intensity corresponding to each target pixel position; the two-dimensional X-ray diffraction pattern includes the position information of multiple pixels and the diffraction intensity corresponding to each pixel; and calculating the proportion of the target component in the sample based on the intensity value corresponding to the target pixel position. However, this patent cannot solve the existing technical problems and cannot meet the needs of this invention.

[0004] The DAWN2 software proposed by J. Filik et al. in 2017 (

[61] Filik J, Ashton A, Chang P, et al. Processing two-dimensional X-ray diffraction and small-angle scattering data in DAWN 2[J]. Journal of applied crystallography, 2017, 50(3): 959-966.) has the ability to compress X-ray diffraction Debye rings into one-dimensional diffraction peaks and rocking curves respectively. However, this method lacks the ability to perform in-depth analysis of the acquired curves and cannot separate and analyze the overlapping diffraction curves of each phase in the subgrain.

[0005] In 2017, D. Collins et al. (Collins DM, D'souza N, Panwisawas C. In-situneutron diffraction during stress relaxation of a single crystal nickel-basesuperalloy[J].Scripta Materialia, 2017, 131: 103-107.) proposed a method for separating the overlapping diffraction peaks of the γ and γ′ phases in nickel-based superalloys during diffraction experiments at spallation neutron sources. This method utilizes {100} γ′ ,{300} γ， Superlattice diffraction peaks are used to help determine the peak position of the γ′ phase in the {200} diffraction peak, thereby separating the overlapping diffraction peaks of the γ and γ′ phases. However, in steady-state neutron sources, the signal-to-noise ratio of superlattice diffraction peaks is low, and the superlattice diffraction peaks may be located at low diffraction angles that are difficult for the detector to reach, so there is a certain probability that superlattice diffraction peaks cannot be obtained. In contrast, this invention can effectively separate and analyze the overlapping diffraction peaks caused by the two-phase structure in the subgrain diffraction peaks without the aid of superlattice diffraction, using the two-dimensional diffraction data itself. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a method and system for processing two-dimensional diffraction data of dual-phase single-crystal materials.

[0007] The two-dimensional diffraction data processing method for dual-phase single-crystal materials provided by the present invention includes:

[0008] Step 1: Establish an orthogonal coordinate system (x, y, z), with the origin at the optical center of the experiment. The positive x-axis coincides with the direction of the incident neutron / X-ray, and the z-axis is vertically upward. Determine the y-axis direction according to the right-hand rule. Calculate the orientation information (θ, η) of each pixel in the two-dimensional surface detector based on diffraction geometry. θ is the angle between the line connecting a single pixel to the optical center and the incident neutron / X-ray, and η is the angle between the line connecting a single pixel to the detector center and the positive z-axis. Define clockwise as the positive direction. Let the number of pixels on the two-dimensional surface detector be N1×N2. The orientation information is represented by two N1×N2 matrices, denoted as Θ and Η.

[0009] Step 2: Combining diffraction geometry and orientation information, set three intensity calibration factors—solid angle factor, polarization factor, and absorption factor—to calibrate the original diffraction intensity, forming a diffraction intensity matrix C(θ,η) of size N1×N2; Step 3: Integrate along the η direction to obtain the rocking curve of the single-crystal sample. By determining the number M of subgrains in the single-crystal sample, use a Gaussian mixture function to fit and analyze the rocking curve to obtain the rocking curve parameters, including the peak position η of each subgrain. RC,j Standard deviation u RC,j Peak strength b RC,j and background noise b RC Where 1≤j≤M,

[0010] Step 4: Using the rocking curve parameters of each subgrain, the diffraction intensity matrix is ​​separated into M N1×N2 subgrains, representing the two-dimensional diffraction intensity matrix C of each subgrain. j (θ,η) enables two-dimensional separation of subgrain diffraction signals;

[0011] Step 5: Use a two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each subgrain after the two-dimensional diffraction data is separated, and obtain the two-dimensional diffraction parameters of the two phases in each subgrain.

[0012] Step 6: Using diffraction geometry and combining the two-dimensional diffraction parameters of the two phases in each subgrain, calculate the interplanar spacing and orientation information of the two phases in each subgrain.

[0013] Preferably, step 3 includes:

[0014] Step 3.1: Determine the central diffraction angle θ1 and the diffraction angle range δθ1, satisfying... C(θ,η) is used as the effective diffraction intensity data;

[0015] Step 3.2: Determine the range of azimuth angle η [η min ,η max ], and step size Δη1, define set A i :

[0016]

[0017] Where, η min For the minimum value in the range, η max It represents the maximum value within the range;

[0018] Step 3.3: By analyzing set A i Calculate the average value of the diffraction intensity to determine the rocking curve I. RC (θ1,η i );

[0019] Step 3.4: Define a one-dimensional Gaussian mixture function Let be the fitting function, where a RC,j η RC,j u RC,j b RC G represents the parameters to be fitted. RC,j (θ1,η i () represents the rocking curve of each subgrain after separation;

[0020] Step 3.5: Define the objective function as mean squared error, i.e. Where N is the number of subgrains;

[0021] Step 3.6: Using the least squares algorithm, adjust the parameters to be fitted and reduce the objective function to obtain the rocking curve parameters of each subgrain.

[0022] Preferably, step 4 includes:

[0023] Step 4.1: Assume that for a specific subgrain, the same parameter η is used. i The pixels have the same diffraction intensity, that is

[0024] Step 4.2: Calculate the relative diffraction intensity matrix of each subgrain using the rocking curve parameters.

[0025] Step 4.3: Calculate the two-dimensional diffraction intensity matrix of each subgrain using the proportional relationship between the relative diffraction intensity matrices of each subgrain.

[0026] Preferably, step 5 includes:

[0027] Step 5.1: Define the two-dimensional bigaussian function GD j (θ1,η1)=G j,1 (θ1,η1)+G j,2 (θ1,η1)+a j,10 Let be the function to be fitted, where:

[0028]

[0029]

[0030] These represent the two-dimensional diffraction peaks produced by the first and second phases in subgrain j, respectively, where the two phases have the same orientation, and the parameter to be fitted is a. j,i ,

[0031] Step 5.2: Define the objective function as mean squared error:

[0032]

[0033] Step 5.3: Use the least squares algorithm to adjust the parameters to be fitted and reduce the objective function to obtain the final values ​​of the parameters to be fitted;

[0034] Step 5.4: For all subgrains, repeat steps 5.1 to 5.3 to obtain the orientation information of the two-phase diffraction peaks in all subgrains within the single crystal sample, denoted as...

[0035] Preferably, step 6 includes:

[0036] Step 6.1: Based on diffraction geometry and the law of reflection, let the parameters to be fitted for a certain phase in the subgrain be (a j,2 ,a j,4 ), and the crystal plane normal vector in the orthogonal coordinate system is (X j Z j ,Y j Solving the following equations simultaneously yields the orientation information of the two phases in the subgrain:

[0037]

[0038] Step 6.2: Based on the incident wavelength and diffraction angle, use Bragg's law 2dsina j,2 =λ, and the interplanar spacing in the subgrains can be obtained by solving for the interplanar spacing.

[0039] The two-dimensional diffraction data processing system for dual-phase single-crystal materials provided by the present invention includes:

[0040] Module M1: Establish an orthogonal coordinate system (x, y, z), with the origin at the optical center of the experiment. The positive x-axis coincides with the direction of the incident neutron / X-ray, and the z-axis is vertically upward. The y-axis direction is determined according to the right-hand rule. Based on diffraction geometry, calculate the orientation information (θ, η) of each pixel in the two-dimensional surface detector. θ is the angle between the line connecting a single pixel in the detector and the optical center and the incident neutron / X-ray, and η is the angle between the line connecting a single pixel and the detector center and the positive z-axis. Clockwise is defined as the positive direction. If the number of pixels on the two-dimensional surface detector is N1×N2, the orientation information is represented by two N1×N2 matrices, denoted as Θ and H.

[0041] Module M2: Combining diffraction geometry and orientation information, three intensity calibration factors—solid angle factor, polarization factor, and absorption factor—are set to calibrate the original diffraction intensity, forming a diffraction intensity matrix C(θ,η) of size N1×N2.

[0042] Module M3: Integrates along the η direction to obtain the rocking curve of the single crystal sample. By determining the number M of subgrains in the single crystal sample, the rocking curve is fitted and analyzed using a Gaussian mixture function to obtain the rocking curve parameters, including the peak position η of each subgrain. RC,j Standard deviation u RC,j Peak strength b RC,j and background noise b RC Where 1≤j≤M,

[0043] Module M4: Using the rocking curve parameters of each subgrain, the diffraction intensity matrix is ​​separated into M N1×N2 units, representing the two-dimensional diffraction intensity matrix C of each subgrain. j (θ,η) enables two-dimensional separation of subgrain diffraction signals;

[0044] Module M5: Uses a two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each subgrain after the two-dimensional diffraction data is separated, and obtains the two-dimensional diffraction parameters of the two phases in each subgrain.

[0045] Module M6: Utilizing diffraction geometry and combining the two-dimensional diffraction parameters of the two phases within each subgrain, calculates the interplanar spacing and orientation information of the two phases in each subgrain.

[0046] Preferably, the module M3 includes:

[0047] Module M3.1: Determine the central diffraction angle θ1 and the diffraction angle range δθ1, which will satisfy... C(θ,η) is used as the effective diffraction intensity data;

[0048] Module M3.2: By determining the range of azimuth angle η [η min ,η max ], and step size Δη1, define set A i :

[0049]

[0050] Where, η min For the minimum value in the range, η max It represents the maximum value within the range;

[0051] Module M3.3: By analyzing set A i Calculate the average value of the diffraction intensity to determine the rocking curve I. RC (θ1,η i );

[0052] Module M3.4: Define a one-dimensional Gaussian mixture function Let be the fitting function, where a RC,j ηRC,j u RC,j b RC G represents the parameters to be fitted. RC,j (θ1,η i () represents the rocking curve of each subgrain after separation;

[0053] Module M3.5: Defines the objective function as mean squared error, i.e. Where N is the number of subgrains;

[0054] Module M3.6: Utilizes the least squares algorithm to adjust the parameters to be fitted and reduce the objective function, thereby obtaining the rocking curve parameters of each subgrain.

[0055] Preferably, the module M4 includes:

[0056] Module M4.1: Suppose that for a specific subgrain, the same parameter η is used. i The pixels have the same diffraction intensity, that is

[0057] Module M4.2: Calculates the relative diffraction intensity matrix of each subgrain using rocking curve parameters.

[0058] Module M4.3: Calculates the two-dimensional diffraction intensity matrix of each subgrain by utilizing the proportional relationship between the relative diffraction intensity matrices of each subgrain.

[0059] Preferably, the module M5 includes:

[0060] Module M5.1: Defines the two-dimensional bigaussian function GD j (θ1,η1)=G j,1 (θ1,η1)+G j,2 (θ1,η1)+a j,10 Let be the function to be fitted, where:

[0061]

[0062]

[0063] These represent the two-dimensional diffraction peaks produced by the first and second phases in subgrain j, respectively, where the two phases have the same orientation, and the parameter to be fitted is a. j,i ,

[0064] Module M5.2: Define the objective function as mean squared error:

[0065]

[0066] Module M5.3: Utilizes the least squares algorithm to adjust the parameters to be fitted, reduce the objective function, and thus obtain the final values ​​of the parameters to be fitted;

[0067] Module M5.4: For all subgrains, repeatedly call modules M5.1 to M5.3 to obtain the orientation information of the two-phase diffraction peaks in all subgrains within the single crystal sample, denoted as...

[0068] Preferably, the module M6 includes:

[0069] Module M6.1: Based on diffraction geometry and the law of reflection, let the parameters to be fitted for a certain phase in a subgrain be (a j,2 ,a j,4 ), and the crystal plane normal vector in the orthogonal coordinate system is (X j Z j ,Y j Solving the following equations simultaneously yields the orientation information of the two phases in the subgrain:

[0070]

[0071] Module M6.2: Based on the incident wavelength and diffraction angle, using Bragg's law 2dsina j,2 =λ, and the interplanar spacing in the subgrains can be obtained by solving for the interplanar spacing.

[0072] Compared with the prior art, the present invention has the following beneficial effects:

[0073] (1) This invention obtains the rocking curve by integrating along the direction and uses the Gaussian mixture function model for fitting analysis. Based on the rocking curve fitting analysis, it is assumed that for a specific subgrain, pixels with the same azimuth angle have the same diffraction intensity, thereby separating the diffraction intensity matrix into the two-dimensional diffraction intensity matrix corresponding to each subgrain, thus solving the problem of difficulty in peak separation caused by the overlap of two-dimensional diffraction signals caused by subgrains.

[0074] (2) This invention uses a two-dimensional double Gaussian function to simulate the two-dimensional diffraction peak shape of a two-phase structure, and sets the fitting parameters based on the assumption that the two-phase structures have the same orientation. The two-dimensional diffraction peaks of the separated individual subgrains are then fitted and analyzed, thereby solving the problem that existing two-dimensional diffraction data processing methods for two-phase single crystal materials cannot effectively separate overlapping diffraction peaks of two phases with similar lattice constants without relying on superlattice diffraction peaks. Attached Figure Description

[0075] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0076] Figure 1 This is the geometric model for the diffraction experiment;

[0077] Figure 2 This is an overall flowchart of the present invention;

[0078] Figure 3 The diffraction intensity of the two-dimensional surface detector;

[0079] Figure 4 It is a swaying curve;

[0080] Figure 5 Two-dimensional diffraction curves for each subgrain;

[0081] Figure 6 The results are the fitting results of the two-dimensional diffraction curves of the subgrain. Detailed Implementation

[0082] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0083] Example 1:

[0084] The method of this invention is applied to the analysis of neutron / X-ray diffraction two-dimensional surface detector data of two-phase single crystal materials. By extracting the diffraction intensity and orientation information of each point in the detector pixel by pixel, and using the one-dimensional rocking curve obtained by integration along the η direction, the two-dimensional diffraction data corresponding to each subgrain is separated. Finally, the two-dimensional diffraction data is fitted with a two-dimensional double Gaussian function to quantitatively analyze the interplanar spacing and orientation information of the two phases in the subgrain.

[0085] like Figure 2 Specifically, it includes the following steps:

[0086] Step 1: Define an orthogonal coordinate system (x, y, z), with the origin at the optical center of the experiment. The positive x-axis coincides with the direction of the incident neutron / X-ray, the z-axis points vertically upward, and the y-axis is determined according to the right-hand rule. For example... Figure 1 Based on diffraction geometry, the orientation information (θ, η) of each pixel in the two-dimensional surface detector is calculated. This is the angle θ between the line connecting a single pixel to the optical center and the incident neutron / X-ray, and the angle η between the line connecting a single pixel to the detector center and the positive z-axis direction, where clockwise is defined as the positive direction. Assuming the number of pixels on the two-dimensional surface detector is N1×N2, the orientation information can be represented by two N1×N2 matrices, denoted as Θ and H.

[0087] Step 2: Combining diffraction geometry and orientation information, set three intensity calibration factors: solid angle factor, polarization factor, and absorption factor, to calibrate the original diffraction intensity, forming a diffraction intensity matrix C(θ,η) of size N1×N2, as shown below. Figure 3 .

[0088] Step 3: Integrate along the η direction to obtain the rocking curve of the single crystal sample, as shown below. Figure 4 By determining the number M of subgrains in a single-crystal sample, and using a mixture of Gaussian functions (i.e., the linear superposition of multiple Gaussian functions), the rocking curve parameters, including the peak position η of each subgrain, are obtained through fitting analysis of the rocking curve. RC,j Standard deviation u RC,j Peak strength b RC,j and background noise b RC ,in,

[0089] Step 3 includes the following steps:

[0090] Step 3.1: Determine the central diffraction angle θ1 and the diffraction angle range δθ1, satisfying... C(θ,η) is used as the effective diffraction intensity data;

[0091] Step 3.2: Determine the range of azimuth angle η [η min ,η max ], and step size Δη1, define set A i :

[0092]

[0093] Step 3.3: By analyzing set A i Calculate the average value of the diffraction intensity to determine the rocking curve I. RC (θ1,η i );

[0094] Step 3.4: Define a one-dimensional Gaussian mixture function Let be the fitting function, where a RC,j η RC,j u RC,j b RC G represents the parameters to be fitted. RC,j (θ1,η i () represents the rocking curve of each subgrain after separation;

[0095] Step 3.5: Define the objective function as mean squared error, i.e.

[0096] Step 3.6: Using the least squares algorithm, adjust the parameters to be fitted and reduce the objective function to obtain the rocking curve parameters of each subgrain.

[0097] Step 4: Using the rocking curve parameters of each subgrain, the diffraction intensity matrix is ​​separated into M N1×N2 subgrains, representing the two-dimensional diffraction intensity matrix C of each subgrain. j (θ,η), thereby achieving two-dimensional separation of subgrain diffraction signals, such as Figure 5 .

[0098] Step 4 includes the following steps:

[0099] Step 4.1: Assume that for a specific subgrain, the same parameter η is used. i The pixels have the same diffraction intensity, that is

[0100] Step 4.2: Based on the assumptions in Step 4.1, calculate the relative diffraction intensity matrix of each subgrain using the rocking curve parameters.

[0101] Step 4.3: Calculate the two-dimensional diffraction intensity matrix of each subgrain using the proportional relationship between the relative diffraction intensity matrices of each subgrain.

[0102] Step 5: Use a two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each subgrain after the two-dimensional diffraction data separation, and obtain the two-dimensional diffraction parameters of the two phases within each subgrain, such as... Figure 6 .

[0103] Step 5 includes the following steps:

[0104] Step 5.1: Define the two-dimensional bigaussian function GD j (θ1,η1)=G j,1 (θ1,η1)+G j,2 (θ1,η1)+a j,10 Let be the function to be fitted, where:

[0105]

[0106]

[0107] These represent the two-dimensional diffraction peaks produced by the first and second phases in subgrain j, respectively, where it is assumed that the two phases have the same orientation, and the parameter to be fitted is a. j,i ,

[0108] Step 5.2: Define the objective function as mean squared error:

[0109]

[0110] Step 5.3: Use the least squares algorithm to adjust the parameters to be fitted and reduce the objective function to obtain the final values ​​of the parameters to be fitted;

[0111] Step 5.4: For all subgrains, repeat steps 5.1-5.3 to obtain the orientation information of the two-phase diffraction peaks in all subgrains within the single crystal sample, denoted as...

[0112] Step 6: Using diffraction geometry and the final values ​​of the parameters to be fitted in Step 5, calculate the interplanar spacing and orientation information of the two phases in each subgrain.

[0113] Step 6 includes the following steps:

[0114] Step 6.1: Based on diffraction geometry and the law of reflection, assume that the parameter to be fitted for a certain phase in the subgrain is (a j,2 ,a j,4 ), and the crystal plane normal vector in the orthogonal coordinate system is (X j Z j ,Y j The orientation information of the two phases in the subgrains can be obtained by solving the following equations simultaneously:

[0115]

[0116] Step 6.2: Based on the incident wavelength and diffraction angle, use Bragg's law 2dsina j,2 =λ, and the interplanar spacing in the subgrains can be solved.

[0117] Example 2:

[0118] The present invention also provides a two-dimensional diffraction data processing system for dual-phase single-crystal materials. The two-dimensional diffraction data processing system for dual-phase single-crystal materials can be implemented by executing the process steps of the two-dimensional diffraction data processing method for dual-phase single-crystal materials. That is, those skilled in the art can understand the two-dimensional diffraction data processing method for dual-phase single-crystal materials as a preferred embodiment of the two-dimensional diffraction data processing system for dual-phase single-crystal materials.

[0119] The two-dimensional diffraction data processing system for dual-phase single-crystal materials provided by the present invention includes: Module M1: establishing an orthogonal coordinate system (x, y, z), with the origin at the optical center of the experiment, the positive x-axis coinciding with the direction of the incident neutron / X-ray, the z-axis pointing vertically upward, determining the y-axis direction according to the right-hand rule, and calculating the orientation information (θ, η) of each pixel in the two-dimensional surface detector according to diffraction geometry, where θ is the angle between the line connecting a single pixel in the detector and the optical center and the incident neutron / X-ray, and η is the angle between the line connecting a single pixel and the detector center and the positive z-axis direction, defining clockwise as the positive direction. The two-dimensional... If the number of pixels on the surface detector is N1×N2, then the orientation information is represented by two N1×N2 matrices, denoted as Θ and H; Module M2: Combining diffraction geometry and orientation information, three intensity calibration factors—solid angle factor, polarization factor, and absorption factor—are set to calibrate the original diffraction intensity, forming a diffraction intensity matrix C(θ,η) of size N1×N2; Module M3: Integrating along the η direction, the rocking curve of the single-crystal sample is obtained. By determining the number M of subgrains in the single-crystal sample, the rocking curve is fitted and analyzed using a Gaussian mixture function to obtain the rocking curve parameters, including the peak position η of each subgrain. RC,j Standard deviation u RC,j Peak strength b RC,j and background noise b RC ,in, Module M4: Using the rocking curve parameters of each subgrain, the diffraction intensity matrix is ​​separated into M N1×N2 units, representing the two-dimensional diffraction intensity matrix C of each subgrain. j (θ,η) enables two-dimensional separation of subgrain diffraction signals; Module M5: uses a two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each subgrain after the two-dimensional diffraction data is separated, and obtains the two-dimensional diffraction parameters of the two phases in each subgrain; Module M6: uses diffraction geometry, combined with the two-dimensional diffraction parameters of the two phases in each subgrain, to calculate the interplanar spacing and orientation information of the two phases in each subgrain.

[0120] The module M3 includes: Module M3.1: Determines the central diffraction angle θ1 and the diffraction angle range δθ1, satisfying... C(θ,η) is used as the effective diffraction intensity data; Module M3.2: By determining the range of azimuth angle η [η mnin ,η max ], and step size Δη1, define set A i : Where, η min For the minimum value in the range, η max The maximum value in the range; Module M3.3: By analyzing set A i Calculate the average value of the diffraction intensity to determine the rocking curve I. RC (θ1,ηi ); Module M3.4: Define a one-dimensional Gaussian mixture function Let be the fitting function, where a RC,j η RC,j u RC,j b RC G represents the parameters to be fitted. RC,j (θ1,η i The symbol represents the rocking curve of each subgrain after separation; Module M3.5: defines the objective function as the mean square error, i.e. Where N is the number of subgrains; Module M3.6: Using the least squares algorithm, adjust the parameters to be fitted and reduce the objective function to obtain the rocking curve parameters of each subgrain.

[0121] The module M4 includes: Module M4.1: Assume that for a specific subgrain, the parameters η are the same. i The pixels have the same diffraction intensity, that is Module M4.2: Calculates the relative diffraction intensity matrix of each subgrain using rocking curve parameters. H; Module M4.3: Calculates the two-dimensional diffraction intensity matrix of each subgrain by utilizing the proportional relationship between the relative diffraction intensity matrices of each subgrain.

[0122] The module M5 includes: Module M5.1: Defines a two-dimensional double Gaussian function. Let be the function to be fitted, where: These represent the two-dimensional diffraction peaks produced by the first and second phases in subgrain j, respectively, where the two phases have the same orientation, and the parameter to be fitted is a. j,i , Module M5.2: Define the objective function as mean squared error: Module M5.3: Utilizes the least squares algorithm to adjust the parameters to be fitted, reducing the objective function to obtain the final values ​​of the parameters to be fitted; Module M5.4: For all subgrains, repeatedly call modules M5.1 to M5.3 to obtain the orientation information of the two-phase diffraction peaks in all subgrains within the single crystal sample, denoted as (a j,2 ,a j,4 ),(a j,7 ,a j,4 ),

[0123] The module M6 includes: Module M6.1: Based on diffraction geometry and the law of reflection, let the fitting parameter of a certain phase in the subgrain be (a j,2 ,aj,4 ), and the crystal plane normal vector in the orthogonal coordinate system is (X j Z j ,Y j Solving the following equations simultaneously yields the orientation information of the two phases in the subgrain: Module M6.2: Based on the incident wavelength and diffraction angle, using Bragg's law 2dsina j,2 =λ, and the interplanar spacing in the subgrains can be obtained by solving for the interplanar spacing.

[0124] Those skilled in the art will understand that, in addition to implementing the system, apparatus, and their modules provided by this invention in purely computer-readable program code, the same program can be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system, apparatus, and their modules provided by this invention can be considered a hardware component, and the modules included therein for implementing various programs can also be considered structures within the hardware component; alternatively, modules for implementing various functions can be considered both software programs implementing the method and structures within the hardware component.

[0125] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, 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. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A method for processing two-dimensional diffraction data of a dual-phase single-crystal material, characterized in that, Comprising: Step 1: Establish an orthogonal coordinate system (x, y, z), with the origin being the optical center of the experiment, the positive direction of the x-axis coinciding with the direction of the incident neutrons / X-rays, the z-axis direction being vertically upward, and the y-axis direction being determined according to the right-hand rule. According to diffraction geometry, calculate the orientation information (θ, η) of each pixel point in the two-dimensional area detector. θ is the angle between the connecting line of a single pixel point in the detector and the optical center and the incident neutrons / X-rays. η is the angle between the connecting line of a single pixel point and the detector center and the positive direction of the z-axis. Define clockwise as the positive direction. Let the number of pixel points on the two-dimensional area detector be N1 x N2. The orientation information is represented by two N1 x N2 matrices, denoted as Θ and H; Step 2: Combine diffraction geometry and orientation information to set three intensity calibration factors: solid angle factor, polarization factor, and absorption factor. Calibrate the original diffraction intensity to form a N1 x N2 size diffraction intensity matrix C(θ, η); Step 3: Integrate in the η direction to obtain the rocking curve of the single crystal sample, determine the number M of subgrains in the single crystal sample, fit the rocking curve using a mixed Gaussian function, and obtain the rocking curve parameters, including the peak position η of each subgrain RC，j , the standard deviation u RC，j , the peak intensity b RC，j , and the background noise b RC , where 1≤j≤M, Step 4: Using the rocking curve parameters of each subgrain, the diffraction intensity matrix is separated into M two-dimensional diffraction intensity matrices C of size N1xN2 representing each subgrain j (θ,η), achieving two-dimensional separation of the subgrain diffraction signals; Step 5: Use two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each sub-grain after two-dimensional diffraction data separation, and obtain the two-dimensional diffraction parameters of each sub-grain; Step 6: Use diffraction geometry to calculate the interplanar spacing and orientation information of the two phases in each sub-grain by combining the two-dimensional diffraction parameters of the two phases in each sub-grain.

2. The method of processing two-dimensional diffraction data of a dual-phase single crystal material of claim 1, wherein, The step 3 comprises: Step 3.1 : Determine the central diffraction angle θ1 and the range of diffraction angles δθ1 that will satisfy C(θ,η) as the effective diffraction intensity data; Step 3.2: Define the set Ai by determining the range of azimuth angles [η min , η max ] and the step size Δη1. wherein η min is the minimum value of the range, η max is the maximum value of the range; Step 3.3: Determine the rocking curve I by averaging the diffraction intensities of the set Ai RC (θ1, η i ); Step 3.4: Definition of the one-dimensional mixed Gaussian function for the fitting function, where, a RC，j , η RC，j , u RC，j , b RC are the parameters to be fitted, G RC，j (θ1, η i ) represents the rocking curve of each subgrain after separation; Step 3.5: Define the objective function as the mean square error, i.e. where N is the number of sub-grains. Step 3.6: Adjust the parameters to be fitted using the least squares algorithm to reduce the objective function, thereby obtaining the rocking curve parameters of each sub-grain.

3. The method of processing two-dimensional diffraction data of a dual-phase single crystal material of claim 2, wherein, The step 4 comprises: Step 4.1 : Let for a particular sub-grain, the pixel points with the same parameter η i have the same diffraction intensity, i.e. Step 4.2: Calculate the relative diffraction intensity matrix of each subgrain using the rocking curve parameters, Step 4.3: Calculate the two-dimensional diffraction intensity matrix of each sub- grain using the mutual proportional relationship between the relative diffraction intensity matrices of each sub-grain, 4. The method of processing two-dimensional diffraction data of a dual-phase single crystal material of claim 3, wherein, The step 5 comprises: Step 5.1 : Definition of the two-dimensional bi-Gaussian function GD j (θ1, η1) = G j，1 (θ1, η1) + G j，2 (θ1, η1) + a j，10 is the function to be fitted, where: respectively represent two-dimensional diffraction peaks generated by the first phase and the second phase in the sub-grain labeled as j, wherein the two phases have the same orientation, and a is the fitting parameter j，i , 1≤i≤10, Step 5.2: Define the objective function as the mean square error: Step 5.3: Adjust the parameters to be fitted using the least squares algorithm to reduce the objective function, thereby obtaining the final value of the parameters to be fitted; Step 5.4: Repeat the execution of Step 5.1~Step 5.3 for all sub-grains to obtain the orientation information of two-phase diffraction peaks in all sub-grains in the single crystal sample, denoted as (a j，2 , a j,4 ), (a j，7 , a j,4 ), 1≤j≤M, 5. The method of processing two-dimensional diffraction data of a dual-phase single crystal material of claim 4, wherein, The step 6 comprises: Step 6.1: Based on diffraction geometry and the law of reflection, let the parameters to be fitted for a certain phase in the subgrain be (a j，2 a j,4 ), and the crystal plane normal vector in the orthogonal coordinate system is (X j Z j Y j Solving the following equations simultaneously yields the orientation information of the two phases in the subgrain: Step 6.2: According to the incident wavelength and diffraction angle, the interplanar spacing in the subgrain is solved by Bragg's law 2dsina j，2 = λ.

6. A two-dimensional diffraction data processing system for a dual-phase single-crystal material, characterized in that, Comprising: Module M1: Establish an orthogonal coordinate system (x, y, z), with the origin being the optical center of the experiment, the positive direction of the x-axis coinciding with the direction of the incident neutrons / X-rays, the z-axis direction being vertically upward, and the y-axis direction being determined according to the right-hand rule. According to diffraction geometry, calculate the orientation information (θ, η) of each pixel point in the two-dimensional area detector. θ is the angle between the connecting line of a single pixel point in the detector and the optical center and the incident neutrons / X-rays. η is the angle between the connecting line of a single pixel point and the detector center and the positive direction of the z-axis. Define clockwise as the positive direction. Let the number of pixel points on the two-dimensional area detector be N1 x N2. The orientation information is represented by two N1 x N2 matrices, denoted as Θ and H; Module M2: Combine diffraction geometry and orientation information to set three intensity calibration factors: solid angle factor, polarization factor, and absorption factor. Calibrate the original diffraction intensity to form a N1 x N2 size diffraction intensity matrix C(θ, η); Module M3: integrating in the direction of η to obtain a rocking curve of the single crystal sample, fitting and analyzing the rocking curve by using a mixed Gaussian function to determine the number M of subgrains in the single crystal sample, and obtaining rocking curve parameters including peak positions η of each subgrain RC,j , standard deviations u RC,j , peak intensities b RC,j , and background noises b RC , where 1≤j≤M, Module M4: using the rocking curve parameters of each subgrain, the diffraction intensity matrix is separated into M N1xN2 size two-dimensional diffraction intensity matrix C representing each subgrain j (θ,η), achieving two-dimensional separation of subgrain diffraction signals; Module M5: Use two-dimensional double Gaussian function to fit and analyze the two-dimensional diffraction intensity matrix of each sub-grain after two-dimensional diffraction data separation, and obtain the two-dimensional diffraction parameters of each sub-grain; Module M6: Use diffraction geometry to calculate the interplanar spacing and orientation information of the two phases in each sub-grain by combining the two-dimensional diffraction parameters of the two phases in each sub-grain.

7. The system for processing two-dimensional diffraction data of a dual-phase single crystal material of claim 6, wherein, The module M3 comprises: Module M3.1 : determining a center diffraction angle θ1 and a diffraction angle range δθ1, which will satisfy C(θ,η) as effective diffraction intensity data; Module M3.2: Define the set Ai by determining the azimuth angle η range [η min , η max ] and the step size Δη1. wherein η min is the minimum value of the range, η max is the maximum value of the range; Module M3.3: Determine the rocking curve I by averaging the diffraction intensities of the set Ai RC (θ1, η i ); Module M3.4: Defining a one-dimensional mixed Gaussian function for the fitting function, wherein a RC,j , η RC,j , u RC,j , b RC are parameters to be fitted, G RC,j (θ1, η i ) represents the rocking curve of each subgrain after separation; Module M3.5: Define the objective function as the mean square error, i.e. where N is the number of subgrains. Module M3.6: Adjusting the parameters to be fitted by using the least square algorithm to reduce the objective function, so as to obtain the rocking curve parameters of each sub-grain.

8. The system for processing two-dimensional diffraction data of a dual-phase single crystal material of claim 7, wherein, The module M4 comprises: Module M4.1 : Let for a certain sub-grain, the pixel points with the same parameter η have the same diffraction intensity, i.e. i ​ Module M4.2: Calculate the relative diffraction intensity matrix of each subgrain with rocking curve parameters, Module M4.3: Calculate the two-dimensional diffraction intensity matrix of each subgrain using the mutual proportional relationship between the relative diffraction intensity matrices of each subgrain, 9. The system for processing two-dimensional diffraction data of a dual-phase single crystal material of claim 8, wherein, The module M5 comprises: Module M5.1 : Defining a two-dimensional bi-Gaussian function GD j (θ1, η1) = G j，1 (θ1, η1) + G j,2 (θ1, η1) + a j,10 is the function to be fitted, where: respectively represent two-dimensional diffraction peaks generated by the first phase and the second phase in the sub-grain labeled as j, wherein the two phases have the same orientation, and the parameters to be fitted are a j，i , 1≤i≤10, Module M5.2: Defining the objective function as the mean square error: Module M5.3: Adjusting the parameters to be fitted by using the least square algorithm to reduce the objective function, so as to obtain the final value of the parameters to be fitted; Module M5.4: repeat calling of module M5.1-module M5.3 for all sub-grains, to obtain the orientation information of two-phase diffraction peaks in all sub-grains in the single crystal sample, denoted as (a j，2 , a j,4 ), (a j，7 , a j,4 ), 1≤j≤M, 10. The system for processing two-dimensional diffraction data of a dual-phase single crystal material of claim 9, wherein, The module M6 comprises: Module M6.1 : According to the diffraction geometry and the law of reflection, let the parameters to be fitted of a phase in a subgrain be (a j，2 , a j,4 ), and the normal vector of the crystal face in the orthogonal coordinate system be (X j , Z j , Y j ), the orientation information of two phases in the subgrain is obtained by solving the following equations simultaneously: Module M6.2: According to the incident wavelength and the diffraction angle, the interplanar spacing in the sub-grain is solved by using Bragg's law 2dsin a j,2 = λ.

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