Slip system activation determination method suitable for typical metal crystal structure materials (FCC, BCC and HCP)

Abstract

The invention discloses a slip system activation determination method suitable for typical metal crystal structure materials (FCC, BCC and HCP), and belongs to the technical field of material analys.The slip system activation determination method comprises the steps that electron backscatter diffraction (EBSD) data of the typical metal crystal structure materials (FCC, BCC or HCP) before and after stretching is imported, and Euler angles of crystal grains are extracted; according to the crystal structure of the introduced material, the crystal symmetry of the material and the initial orientation of crystal grains are defined; introducing a Taylor axis (rotation axis), and calculating the corresponding Taylor axis according to the crystal structure and the slip system of the introduced material; setting a rotation angle range and a rotation step length so as to simulate the crystal orientation after the initial Euler angle rotates around different Taylor axes by different angles; simulating the rotation of the initial Euler angle of the crystal around the Taylor axis, and calculating the difference between the initial Euler angle and the target Euler angle at different rotation angles around each Taylor axis; and according to a calculation result, evaluating the activated Taylor axis and a corresponding slip system thereof, and a rotation angle and a rotation direction experienced by the crystal grain in an actual slip process. According to the method, the actual slippage system of the crystal grains and the corresponding rotation angle can be accurately determined, the precision of material slippage behavior analysis of typical metal crystal structures (FCC, BCC and HCP) is effectively improved, the limitation of a traditional method in slippage transmission prediction is overcome, and the prediction accuracy is improved. And reliable theoretical support is provided for mechanical property optimization, design improvement and engineering application of materials.

Description

Technical Field

[0001] This invention relates to the field of materials analysis technology, and in particular to a method for determining the activation of slip systems applicable to typical metallic crystal structures (FCC, BCC, and HCP). Background Technology

[0002] Grain boundaries play an important role in the plastic deformation of polycrystalline materials. At room temperature and high temperature, the movement of dislocations is either hindered by grain boundaries or slips through grain boundaries, thus significantly affecting the mechanical properties of polycrystalline materials, such as fracture and fatigue behavior. When grain boundaries are impenetrable, dislocations tend to accumulate at the grain boundaries, resulting in locally obstructed slip bands or lattice curvature. Dislocation pile-up leads to strong back stress, which helps strengthen materials, especially small-grained materials. On the other hand, the local stress concentration caused by dislocation pile-up can also induce cracks at grain boundaries, deteriorating the plasticity of the material. If dislocations can slip through grain boundaries, continuous slip traces and lower stress concentration will appear at the grain boundaries. In this case, the deformation of the local lattices adjacent to each other on both sides of the grain boundary is relatively compatible, which is an important factor for the material to obtain high ductility. Given its importance in the plastic deformation of polycrystalline materials, different parameters have been proposed to predict the slip propagation behavior of dislocations. Slip propagation is closely related to two factors: (1) geometric arrangement. The slip surfaces and slip directions of the entry and exit slip systems should be consistent, which can be achieved using the Luster-Morris parameters. To evaluate, among them This represents the angle between the normals of the slip surface. This represents the angle between the Burgers vectors entering and exiting the slip system. The probability of slip transfer varies with... (2) Residual Burgers vector. After a dislocation crosses a grain boundary, it usually leaves a residual Burgers vector at the grain boundary. Due to its large size This alters the structure and energy of grain boundaries, induces strain accumulation, and promotes the nucleation of microcracks at grain boundaries. Therefore, a smaller residual Burgers vector is beneficial for slip transfer. Using a scanning electron microscope equipped with EBSD combined with slip trace analysis can yield a wealth of observations to determine whether slip transfer occurs at grain boundaries.

[0003] Most slip transfer studies have been conducted in materials with typical metallic crystal structures (FCC, BCC, and HCP), where plastic deformation of each grain can be achieved by activating one or more slip systems. When the Luster-Morris parameter... When the value approaches 1, the slip system in crystal A Slip system in crystal B The possibility of transfer is high. Therefore, when the slip surface of the activated slip system has a low orientation difference and a residual Burgers vector... When the value is small, slip propagation is favorable, and these conditions are likely to be satisfied at low-angle grain boundaries. It should be noted that, based on... and / or Geometric criteria are not entirely predictive; Higher values ​​and Even with lower values, there are instances where slip transfer does not occur (and vice versa). These inconsistencies are attributed to the limitations of experimental methods, particularly in slip trace analysis. While this method can provide information about the slip surface, it cannot directly reveal the actual slip direction. In traditional slip trace analysis, the slip direction is usually assumed to have the maximum Schmidt factor. However, due to deformation constraints, this assumption is often not entirely valid. During actual grain deformation, local stress fields affect the activation of slip systems, meaning that the slip system with the maximum Schmidt factor is not always the actually activated slip system, especially under complex stress states or with large residual stresses.

[0004] Therefore, relying solely on the maximum value of the Schmidt factor to determine the activation state of a slip system may lead to misjudgments in slip transfer analysis. In such cases, the analysis results of slip transfer will be limited by the influence of local stress, making it impossible to correctly identify the activated slip system and thus hindering a comprehensive understanding of the actual slip behavior of materials.

[0005] To overcome this limitation, a new method is urgently needed to accurately and clearly determine the specific slip system activated by each grain under different stress conditions, thereby providing a more precise basis for slip transfer analysis. Summary of the Invention

[0006] The purpose of this invention is to provide a method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) to overcome the defects and shortcomings in existing material analysis processes.

[0007] To achieve the above objectives, this invention provides a method for determining the activation of slip systems applicable to typical metallic crystal structures (FCC, BCC, and HCP), comprising the following steps:

[0008] S1. Import electron backscatter diffraction (EBSD) data of typical metallic crystal structures (FCC, BCC or HCP) before and after stretching, and extract the Euler angles of the grains.

[0009] S2. Based on the crystal structure of the imported material, define the crystal symmetry and initial orientation of the grains;

[0010] S3. Introduce Taylor axis (rotation axis) and calculate its corresponding Taylor axis based on the crystal structure and slip system of the introduced material;

[0011] S4. Set the rotation angle range and rotation step size to simulate the crystal orientation after the initial Euler angles have undergone different angle rotations around different Taylor axes.

[0012] S5. Simulate the initial Euler angle of the crystal rotating about the Taylor axis, and calculate the difference between the target Euler angle and the initial Euler angle at different rotation angles around each Taylor axis.

[0013] S6. Based on the calculation results, evaluate the activated Taylor axis and its corresponding slip system, as well as the rotation angle and rotation direction experienced by the grain during the actual slip process.

[0014] Preferably, S1 specifically includes the following:

[0015] S11. Import the EBSD data before and after stretching into the computing environment, and use data visualization tools to draw the IPF (Inverse Pole Figure) of the grains to visually display the orientation distribution of the grains.

[0016] S12. Select the target grain in the IPF diagram and obtain the average orientation of the selected grain using a data processing tool, which serves as the overall orientation description of the grain.

[0017] S13. Extract the average Euler angle before grain stretching and define it as the initial Euler angle; at the same time, extract the average Euler angle after grain stretching and define it as the target Euler angle for subsequent rotation analysis and Euler angle difference calculation.

[0018] Preferably, S2 specifically includes the following:

[0019] S21. Based on the point group and lattice constant of the metal crystal structure (FCC, BCC or HCP) material under study, define the crystal symmetry of the metal crystal structure (FCC, BCC or HCP) material to ensure that the symmetry characteristics of the crystal are accurately reflected in subsequent analysis.

[0020] S22. Based on this, the initial orientation of the grain is defined by the Euler angles defined by Bunge. The Bunge Euler angles are a widely used method for describing crystal orientation in materials science, especially in electron backscatter diffraction (EBSD) analysis, where they have almost become the standard orientation description method.

[0021] Preferably, S3 specifically includes the following:

[0022] S31. When the slip system of a typical metallic crystal structure (FCC, BCC and HCP) is activated, the crystal will rotate around the Taylor axis corresponding to its slip system. The corresponding Taylor axis is calculated according to different slip systems, and each Taylor axis corresponds to a specific slip system.

[0023] S32. Based on crystal symmetry, Taylor axes corresponding to different slip systems are defined. These Taylor axes will be used to simulate the deformation process of grains under different slip systems.

[0024] Preferably, the specific operation in S4 is as follows: set the rotation range to -20° to 20°, the rotation step size to 0.01°, a positive rotation angle represents clockwise rotation along the rotation axis (Taylor axis), and a negative rotation angle represents counterclockwise rotation along the rotation axis (Taylor axis). For each Taylor axis, iterate through the rotation angle range and record the Euler angle difference value under each rotation step size. Finally, obtain 4000 Euler angle difference values ​​corresponding to each Taylor axis and compare them with the rotation angle.

[0025] Preferably, step S5 specifically includes the following steps:

[0026] S51. Based on the set rotation step size and rotation range, calculate the orientation of the grain after rotating the initial Euler angle around the Taylor axis, and extract the rotated Euler angle; during this process, the initial orientation of the grain will rotate along each Taylor axis according to the set rotation step size and rotation range to simulate its deformation behavior under different slip system activation conditions; by gradually adjusting the rotation angle, the grain orientation at each angle can be obtained.

[0027] S52. For each rotation angle, calculate the difference between the rotated Euler angle and the target Euler angle. The sum of the absolute values ​​of the differences is usually used to measure the closeness between the two. In this way, the similarity between the rotated Euler angle and the target Euler angle can be quantified, thereby evaluating the effectiveness of the rotation angle. The calculation of this difference sum provides key data support for the subsequent determination of the activated slip system and the corresponding rotation angle.

[0028] S53. By traversing all the set rotation angles and Taylor axes, a loop structure is used to perform a detailed analysis of each Taylor axis. For each Taylor axis, the set rotation angle range is traversed, and the difference between the Euler angle and the target Euler angle under each rotation step is calculated. In this way, by recording the Euler angle differences under all rotation angles, a complete set of Euler angle difference data can be generated for each Taylor axis.

[0029] Preferably, step S6 specifically includes the following steps:

[0030] S61. Compare the Euler angle differences calculated for all Taylor axes, evaluate the minimum Euler angle difference for each Taylor axis, and determine the Taylor axis with the smallest Euler angle difference through this comparison, that is, determine the slip system that is actually activated during the deformation process.

[0031] S62. Select the Taylor axis with the smallest difference, and consider the slip system corresponding to this Taylor axis as the actually activated slip system. At this time, the activation degree of this slip system has been verified by the minimum Euler angle difference, representing the main slip system of the grain in actual deformation. It should be noted that in a certain crystal structure, some slip systems cannot be one-to-one with Taylor axes. This situation only exists in the body-centered cubic (BCC) crystal structure {112}. <111> The glide systems and the {-1011}<-12-10> glide systems with the hexagonal close-packed (HCP) crystal structure, and the {112} glide systems with the body-centered cubic (BCC) crystal structure. <111> Taking slip systems as an example, there are 12 independent slip systems of this type. Due to the phenomenon of coincidence of rotation axes under crystal symmetry, these slip systems actually correspond to only 6 different Taylor rotation axes. That is, there is a situation where "one Taylor axis corresponds to two slip systems". Based on the above characteristics, this only applies to the {112} of the body-centered cubic (BCC) crystal structure. <111> To determine the Taylor axis corresponding to the {-1011}<-12-10> slip system of the hexagonal close-packed (HCP) crystal structure, an additional step is required: by comparing the experimental trace with the candidate slip surface trace, the specific slip surface where slip activity actually occurred can be effectively determined, thereby completing the unique identification of the specific slip system.

[0032] S63. Record the rotation angle corresponding to the minimum difference. This rotation angle reflects the degree of rotation experienced by the grain during the actual slip process. By analyzing the rotation angle, we can further understand the degree of crystal orientation change that occurs during the deformation process.

[0033] S64. Determine the rotation direction during grain slip based on the positive or negative value of the rotation angle; a positive rotation angle indicates that the grain rotates clockwise along the Taylor axis, while a negative rotation angle indicates that the grain rotates counterclockwise along the Taylor axis.

[0034] The design concept of this invention is to overcome the limitations of existing material analysis methods by accurately calculating and analyzing the slip system activation of grains. Specifically, in traditional slip transfer analysis, the slip direction is determined solely by the maximum value of the Schmidt factor, which may lead to inaccurate results. By extracting the initial Euler angles before grain stretching and the target Euler angles after stretching, and simulating and analyzing the orientation changes of grains during deformation, a more comprehensive and accurate method for determining slip system activation is proposed. This method can more accurately determine the slip behavior of grains during deformation, providing a more reliable theoretical basis for the plastic deformation analysis and performance optimization of materials.

[0035] This invention employs a method for determining the activation of slip systems applicable to typical metallic crystal structures (FCC, BCC, and HCP), and has the following innovative features:

[0036] 1) Unified decision framework across crystal structures: A decision process based on Taylor axis rotation simulation orientation and EBSD stretching average orientation registration is proposed. The same algorithm is applicable to three typical metal crystal structures: FCC, BCC and HCP, avoiding the fragmentation of methods for single crystal structures.

[0037] 2) High-resolution search: Using the sum of the absolute values ​​of the differences between the target Euler angles and the simulated Euler angles as the matching criterion, a measurable and sortable comparison of the "Taylor axis-rotation angle" is performed; a high-resolution scan of 4000 samples / axis is formed within a range of ±20° and a step size of 0.01°, realizing a high-resolution and computationally controllable engineering search.

[0038] 3) Equivalent rotation axis differentiation and unique identification mechanism: for BCC{112} <111> In the case of multiple slip systems corresponding to one Taylor axis in HCP{1-100}<11-20>, the experimental slip trace is compared with the candidate slip surface trace. Under the condition of multiple slip systems corresponding to one Taylor axis, the specific slip surface / slip system can still be uniquely determined.

[0039] 4) Cooperative identification of slip system activation and rotation parameters: The method simultaneously provides the activated slip system, the actual rotation angle and its positive and negative rotation directions, expanding from "whether it is activated" to an interpretable characterization of "how it rotates".

[0040] Therefore, this invention employs a method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP), which has the following beneficial effects:

[0041] 1) The slip system activation determination method applicable to typical metallic crystal structure materials (FCC, BCC and HCP) implemented by the present invention has successfully achieved accurate determination and analysis of grain slip system activation.

[0042] 2) In practical applications, this method can overcome the limitations of traditional slip transfer analysis methods, especially the local applicability problem of the Schmidt factor maximization method.

[0043] 3) By traversing the rotation range of the grain under different Taylor axes, the actual activated slip system of each grain and its rotation angle and direction during the slip process can be accurately determined.

[0044] 4) The activation status of slip systems can be effectively determined under different stress and grain boundary conditions. After comparing the calculation results of different Taylor axes, the slip system with the smallest difference from the target Euler angle can be selected, and its physical behavior in the actual deformation process can be further determined.

[0045] Furthermore, this method enables efficient and precise analysis, handling large amounts of data and providing accurate calculation results. Through this approach, materials scientists and engineers can more accurately understand and predict the plastic deformation behavior of typical metallic crystal structures (FCC, BCC, and HCP) under complex mechanical conditions, thus providing important theoretical basis for the design and optimization of polycrystalline materials. The implementation of this invention not only enhances the accuracy of slip transfer analysis but also provides new ideas and tools for the field of materials science, possessing broad application prospects and engineering value.

[0046] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0048] Figure 1 This is a flowchart of the method for determining the activation of the slip system provided in Embodiments 1, 2 and 3 of the present invention;

[0049] Figure 2 This is an implementation architecture diagram of the slip system activation determination method provided in Embodiments 1, 2 and 3 of the present invention;

[0050] Figure 3 These are schematic diagrams of Euler angles for Embodiments 1, 2, and 3 of the present invention;

[0051] Figure 4 This is an output result diagram of a method for determining the slip system activation of an FCC crystal structure material provided in Embodiment 4 of the present invention. Detailed Implementation

[0052] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0053] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0054] Example 1

[0055] This embodiment provides a method for determining the activation of slip systems in FCC materials, which may specifically include the following steps:

[0056] 1) Import the electron backscatter diffraction data before and after stretching, draw the inverse pole figure, select the target grain and calculate the average orientation to obtain the three components of the initial Euler angle and the three components of the target Euler angle.

[0057] 2) Convert the two orientations mentioned above into initial orientation matrices and target orientation matrices respectively, and set the symmetry of the point group to which the material belongs for subsequent calculations.

[0058] 3) Enumerate the normals of the {111} face family, and the normals orthogonal to them. <110> The slip directions were paired one by one, and the Taylor axes were obtained by "cross product of normal and slip direction and normalization". Equivalent repetitions were removed under the action of symmetry to obtain twelve Taylor axes, and the specific slip surfaces and slip directions corresponding to them were recorded. The results are shown in Table 1.

[0059] 4) Set the rotation angle range to -20° to 20°, with a step size of 0.01°, so that each Taylor axis forms four thousand angle samples.

[0060] 5) The general method of axis-angle rotation involves rotating the initial orientation matrix around each Taylor axis by a set angle to obtain the rotated orientation matrix, which is then converted into the three components of Euler angles.

[0061] 6) Calculate the difference value: Take the absolute value of the difference between the three components of the rotated Euler angle and the three components of the target Euler angle, and sum them.

[0062] 7) For each Taylor axis, form an "angle-difference value" sequence and record the minimum difference value on that axis and its corresponding angle.

[0063] 8) Select the line with the minimum global difference value among all Taylor axes, and determine the associated slip surface and slip direction as the actual activated slip system.

[0064] 9) Determine the rotation direction based on the positive or negative value of the obtained optimal angle (positive value indicates clockwise, negative value indicates counterclockwise), and the absolute value of the angle is on the order of rotation; output the sliding system, rotation angle, rotation direction and minimum difference value, and can simultaneously provide "angle-difference value" for intuitive verification.

[0065] Table 1. FCC crystal structure glide systems and their corresponding Taylor axes

[0066] Sliding system Taylor axis (111)[01-1] [-211] (111)[-101] [1-21] (111)[1-10] [11-2] (-1-11)[0-1-1] [2-11] (-1-11)

[101] [-121] (-1-11)[-110]

[112] (-111)[01-1]

[211] (-111)

[101] [12-1] (-111)[-1-10] [1-12] (1-11)[0-1-1] [21-1] (1-11)[-101]

[121] (1-11)

[110] [-112]

[0067] Example 2

[0068] This embodiment provides a method for determining the activation of slip systems in BCC materials, which may include the following steps:

[0069] 1) Set the material symmetry to the point group of a body-centered cubic crystal; the acquisition of the initial and target Euler angles and their matrix representation are the same as in Example 1.

[0070] 2) The construction range of the Taylor axis includes {110} <111> {112} <111> {123} <111> The results of the three types of slip system combinations are shown in Table 2; where {112} <111> A situation arises where "one Taylor axis corresponds to two slip systems".

[0071] 3) Set the rotation angle range to -20° to 20°, with a step size of 0.01°. The rest of the procedures for angle scanning, rotation calculation, and difference value evaluation are the same as in Example 1.

[0072] 4) When "one axis, multiple systems" occurs, the slip trace is uniquely determined: the experimental slip trace direction of the grain in the sample surface is extracted from the electron backscatter diffraction image; the normal of the candidate slip surface is transformed to the sample coordinates and then cross-multiplied with the sample surface normal to obtain the theoretical trace direction; the angle between the experimental trace and each theoretical trace is calculated, and the one with the smallest angle is taken as the actual slip surface, thus uniquely determining the specific slip system.

[0073] 5) The remaining steps regarding the selection of the optimal axis and angle, as well as the output of results, are the same as in Example 1 and will not be repeated here.

[0074] Table 2. Slip systems of BCC crystal structure and their corresponding Taylor axes

[0075] Slip system type Number of slip systems Taylor axis Number of Taylor axes {110}<111> 12 <112> 12 {112}<111> 12 <110> 6 {123}<111> 24 <145> 24

[0076] Example 3

[0077] This embodiment provides a method for determining the activation of slip systems in HCP materials, which may include the following steps:

[0078] 1) Set the material symmetry to the point group of a hexagonal crystal; the acquisition of the initial and target orientations and their matrix representation are the same as in Example 1.

[0079] 2) The construction range of the Taylor axis includes combinations of the base plane {0001}<11−20>, the cylindrical plane {1−100}<11−20>, the conical plane {10−11}<2−1−13>, and {−1011}<−12−10>; among them, {1−100}<11−20> exhibits "one axis, multiple systems". The calculation results of the Taylor axis are shown in Table 3.

[0080] 3) Set the rotation angle range to -20° to 20°, with a step size of 0.01°. The rest of the procedures for angle scanning, rotation calculation, and difference value evaluation are the same as in Example 1.

[0081] 4) When "one axis and multiple systems" occur, the experimental slip trace direction in the sample surface is compared with the theoretical trace direction of each candidate slip surface one by one according to the method described in Example 2, and the one with the smallest included angle value is selected to determine the specific slip surface and slip system.

[0082] 5) The remaining steps regarding the selection of the optimal result and the output of the result are the same as in Example 1, and will not be repeated here.

[0083] Table 3. HCP crystal structure slip systems and their corresponding Taylor axes

[0084] Slip system type Number of slip systems Taylor axis Number of Taylor axes {0001}<11-20> 3 <1-100> 3 {1-100}<11-20> 3 <0001> 1 {-1011}<-12-10> 6 <10-12> 6 {10-11}<2-1-13> 12 <1-32-1> 12

[0085] Example 4

[0086] The following Example 4 is a specific implementation based on Example 1, and this is hereby explained.

[0087] The target grains of the face-centered cubic material were determined according to the method of Example 1. Among the twelve Taylor axes, axis number four gave the smallest Euler angle difference of 5.5117, corresponding to a rotation angle of 15.44° (positive). The minimum differences of the other axes were significantly larger, for example, axis number two was 10.8047, showing a clear single dominant optimum; the Taylor axis orientations output by the program were labeled as [2-11].

[0088] Based on this, it is confirmed that the actual activated slip system of the grain in this deformation corresponds to the Taylor axis [2-11], i.e., (-1-11)[0-1-1]. The rotation direction is determined to be clockwise based on the positive angle value, and the rotation magnitude is 15.44°. The determination result has sufficient discriminative power and stability.

[0089] In summary, this invention can determine the actual activated slip system of each grain based on electron backscatter diffraction (EBSD) data of typical metallic crystal structures (FCC, BCC, and HCP) before and after stretching. This provides a precise foundation for slip transfer research and further analysis of crystal deformation behavior. By accurately identifying and determining the activated slip system, this invention not only overcomes the limitation of traditional methods that rely solely on the maximum value of the Schmidt factor, but also obtains the rotation angle and direction of each grain during material deformation. This method provides a powerful tool for a deeper understanding of the slip behavior of materials under complex stress environments, especially in revealing the intergranular interactions and their impact on macroscopic mechanical properties at the microscale. By clarifying the specific activated slip system of each grain during deformation, the plastic deformation behavior of materials can be better predicted, their mechanical properties improved, and thus, the improvement and engineering applications of materials guided. The method proposed in this invention is not only applicable to the study of crystal plastic deformation during stretching, but can also be extended to various loading methods such as compression and shearing, demonstrating broad applicability and promising prospects for application. Furthermore, by combining this method with three-dimensional EBSD technology, simultaneous analysis of slip system distribution and grain orientation evolution on a spatial scale can be achieved, thus providing crucial support for constructing multi-scale constitutive models, optimizing processing techniques, and developing high-performance metallic materials. In addition, the efficiency and accuracy of this invention's method enable its widespread application in large-scale computations and complex data analysis, providing a more reliable analytical tool for related fields of materials science and engineering.

Claims

1. A method for determining the activation of slip systems applicable to typical metallic crystal structures (FCC, BCC, and HCP), characterized in that, Includes the following steps: S1. Import electron backscatter diffraction (EBSD) data of typical metallic crystal structures (FCC, BCC or HCP) before and after stretching, and extract the Euler angles of the grains. S2. Based on the crystal structure of the imported material, define the crystal symmetry and initial orientation of the grains; S3. Introduce Taylor axis (rotation axis) and calculate its corresponding Taylor axis based on the crystal structure and slip system of the introduced material; S4. Set the rotation angle range and rotation step size to simulate the crystal orientation after the initial Euler angles have undergone different angle rotations around different Taylor axes. S5. Simulate the initial Euler angle of the crystal rotating around the Taylor axis, and calculate the difference between the target Euler angle and the initial Euler angle at different rotation angles around each Taylor axis. S6. Based on the calculation results, evaluate the activated Taylor axis and its corresponding slip system, as well as the rotation angle and rotation direction experienced by the grain during the actual slip process.

2. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, Step 1 specifically includes: S11. Import the EBSD data before and after stretching into the computing environment, and use data visualization tools to draw the IPF (Inverse Pole Figure) of the grains to visually display the orientation distribution of the grains. S12. Select the target grain in the IPF diagram and obtain the average orientation of the selected grain using a data processing tool, which serves as the overall orientation description of the grain. S13. Extract the average Euler angle before grain stretching and define it as the initial Euler angle; at the same time, extract the average Euler angle after grain stretching and define it as the target Euler angle for subsequent rotation analysis and Euler angle difference calculation.

3. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, Step 2 specifically includes: S21: Based on the point group and lattice constant of the studied metallic crystal structure (FCC, BCC, or HCP) material, define the crystal symmetry of the metallic crystal structure (FCC, BCC, or HCP) material to ensure that the symmetry characteristics of the crystal are accurately reflected in subsequent analysis; S22: Based on this, the Euler angles defined by Bunge are used to define the initial orientation of the grains.

4. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, Step 3 specifically includes: S31. When the slip system of a typical metallic crystal structure (FCC, BCC and HCP) is activated, the crystal will rotate around the Taylor axis corresponding to its slip system. The corresponding Taylor axis is calculated according to different slip systems, and each Taylor axis corresponds to a specific slip system. S32. Based on crystal symmetry, Taylor axes corresponding to different slip systems are defined. These Taylor axes will be used to simulate the deformation process of grains under different slip systems.

5. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, In step 4: the rotation range is set to -20° to 20°, the rotation step is 0.01°, a positive rotation angle represents clockwise rotation along the rotation axis (Taylor axis), and a negative rotation angle represents counterclockwise rotation along the rotation axis (Taylor axis). For each Taylor axis, the rotation angle range is traversed, and the Euler angle difference value under each rotation step is recorded. Finally, 4000 Euler angle differences corresponding to each Taylor axis are obtained and compared with the rotation angle.

6. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, Step 5 specifically includes: S51. Based on the set rotation step size and rotation range, calculate the orientation of the grain after rotating the initial Euler angle around the Taylor axis, and extract the rotated Euler angle; during this process, the initial orientation of the grain will rotate along each Taylor axis according to the set rotation step size and rotation range to simulate its deformation behavior under different slip system activation conditions; by gradually adjusting the rotation angle, the grain orientation at each angle can be obtained. S52. For each rotation angle, calculate the difference between the rotated Euler angle and the target Euler angle. The sum of the absolute values ​​of the differences is usually used to measure the closeness between the two. In this way, the similarity between the rotated Euler angle and the target Euler angle can be quantified, thereby evaluating the effectiveness of the rotation angle. The calculation of this difference sum provides key data support for the subsequent determination of the activated slip system and the corresponding rotation angle. S53. By traversing all the set rotation angles and Taylor axes, a loop structure is used to perform a detailed analysis of each Taylor axis. For each Taylor axis, the set rotation angle range is traversed, and the difference between the Euler angle and the target Euler angle under each rotation step is calculated. In this way, by recording the Euler angle differences under all rotation angles, a complete set of Euler angle difference data can be generated for each Taylor axis.

7. The method for determining the slip system activation applicable to typical metallic crystal structure materials (FCC, BCC, and HCP) according to claim 1, characterized in that, Step 6 specifically includes: S61. Compare the Euler angle differences calculated for all Taylor axes, evaluate the minimum Euler angle difference for each Taylor axis, and determine the Taylor axis with the smallest Euler angle difference through this comparison, that is, determine the slip system that is actually activated during the deformation process. S62. Select the Taylor axis with the smallest difference, and consider the slip system corresponding to this Taylor axis as the actually activated slip system. At this time, the activation degree of this slip system has been verified by the minimum Euler angle difference, representing the main slip system of the grain in actual deformation. If this Taylor axis corresponds to the {112} of the body-centered cubic (BCC) crystal structure. <111> When dealing with slip systems or {-1011}<-12-10> slip systems of hexagonal close-packed (HCP) crystal structures, an additional step is required: comparing the experimental trace with the candidate slip surface trace. This can effectively determine the specific slip surface where slip activity actually occurred, thereby completing the unique identification of the specific slip system. S63. Record the rotation angle corresponding to the minimum difference. This rotation angle reflects the degree of rotation experienced by the grain during the actual slip process. By analyzing the rotation angle, we can further understand the degree of crystal orientation change that occurs during the deformation process. S64. Determine the rotation direction during grain slip based on the sign of the rotation angle; a positive rotation angle indicates that the grain rotates clockwise along the Taylor axis, while a negative rotation angle indicates that the grain rotates counterclockwise along the Taylor axis.

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