A method and system for measuring interfacial strain energy of metallic materials

Abstract

The application discloses a kind of method and system for measuring metal material interface strain energy, comprising: metal material is heated and treated, obtains the aging sample of metal material;The aging sample of metal material is cut and polished, and transmission electron microscope sample is obtained;Composition energy spectrum analysis and diffraction spot calibration are carried out to transmission electron microscope sample, the type and structure of precipitated phase are determined;High-resolution image at the interface of the precipitated phase and matrix is obtained;Based on high-resolution image at the interface, the region at the interface of matrix and precipitated phase is analyzed, obtains the strain component in different directions at the interface of analysis region, obtains the strain field distribution at the interface;Based on the strain component at the interface of matrix and precipitated phase, the strain energy at the interface is obtained;The strain energy at the interface is read, and the interface strain energy distribution result graph is obtained.The application obtains the strain distribution at the interface by high-resolution image at the interface of precipitated phase and matrix, increases the reliability of test.

Description

Technical Field

[0001] This invention belongs to the field of nanoscale metallic materials and relates to a method and system for measuring the interfacial strain energy of metallic materials. Background Technology

[0002] Precipitation strengthening is a common method to improve the strength of metallic materials. It mainly involves using appropriate heat treatment processes to precipitate coherent or semi-coherent phases in the matrix of the metallic material, which hinder the movement of dislocations, thereby improving the yield strength or tensile strength of the metallic material.

[0003] Ferritic stainless steels develop precipitates during welding and service at varying temperatures. Improper welding processes can lead to σ-phase precipitation, prolonged service at 300–550°C can result in G-phase precipitation, and improper heat treatment can cause Cr2N and M23C6 precipitates. These precipitates, due to their different structure and lattice constants from the ferrite matrix, create a large lattice distortion strain field at the precipitate-matrix interface. This strain field affects the hardness, plasticity, strength, and corrosion resistance of ferritic stainless steels. Copper alloys undergoing rolling and solution-aging treatment will form (Ni,Co)2Si precipitates during the aging process. The strain at the precipitate-matrix interface affects the mechanical properties and electrical conductivity of the copper alloy. Due to limitations in current experimental measurement methods, it is difficult to comprehensively analyze the strain distribution at the precipitate-matrix interface at the nanoscale.

[0004] Many studies have reported the application of X-ray diffraction and blind hole methods in residual stress measurement. However, the measurement results obtained by these methods are statistical and cannot reflect the stress and strain distribution at the interface between a specific precipitate and the matrix. Therefore, there is an urgent need for a method that can measure the interfacial strain energy of metallic materials. Summary of the Invention

[0005] The purpose of this invention is to solve the problems in the prior art and provide a method and system for measuring the interfacial strain energy of metallic materials. By obtaining a high-resolution image of the interface between the precipitated phase and the matrix, the strain distribution at the interface can be obtained, thereby increasing the reliability of the test.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] A method for measuring the interfacial strain energy of metallic materials includes:

[0008] Heat treatment is performed on metallic materials to obtain aged samples of the metallic materials;

[0009] The aged metal material samples were cut and polished to obtain transmission electron microscope (TEM) samples.

[0010] The compositional energy dispersive spectroscopy (EDS) analysis and diffraction spot calibration of the transmission electron microscopy (TEM) samples were performed to determine the type and structure of the precipitated phases.

[0011] Obtain a high-resolution image of the interface between the precipitated phase and the matrix;

[0012] Based on the high-resolution image at the interface, the region at the interface between the matrix and the precipitated phase is analyzed to obtain the strain components in different directions at the interface of the analysis region, and the strain field distribution at the interface is obtained.

[0013] Based on the strain components at the interface between the matrix and the precipitated phase, the strain energy at the interface is obtained.

[0014] Read the strain energy at the interface and obtain the strain energy distribution result map at the interface.

[0015] A further improvement of the present invention is that:

[0016] The metal material is heated to obtain aged samples, specifically: ferritic stainless steel is held in a box-type resistance furnace for 300 to 1000 hours at a holding temperature of 350 to 750°C to obtain aged samples containing precipitates of different sizes and types in the ferrite; or a deep-cryogenic copper alloy is held at 450 to 550°C for 1 to 5 hours to obtain aged samples with precipitates.

[0017] The aged metal samples were cut and polished to obtain transmission electron microscopy (TEM) samples, specifically:

[0018] The aged metal sample was cut into thin slices of 15mm×15mm×0.6mm and polished with metallographic sandpaper until the slice thickness was less than 100μm. The slices were then punched into circular slices with a diameter of 3mm and polished again with metallographic sandpaper until the slice thickness was less than 50μm. The polished slices were then placed in an electrolytic double-jet thinner or an ion thinner for thinning treatment to obtain the transmission electron microscope sample.

[0019] The electrolytic double spray solution is 95% ethanol + 5% perchloric acid.

[0020] To determine the type and structure of the precipitated phase, the transmission electron microscope (TEM) sample was subjected to compositional energy dispersive spectroscopy (EDS) analysis and diffraction spot calibration. Specifically, the TEM sample was placed in the TEM for observation, with the observation area being the thin region near the thinning aperture, which contains both matrix and precipitated phase. First, the TEM sample was subjected to compositional energy dispersive spectroscopy analysis to obtain the chemical composition of the matrix and precipitated phase within the observation area. Second, diffraction spots were obtained along the direction of the region, and the diffraction spots were calibrated. Combined with the chemical composition of the precipitated phase, the type and structure of the precipitated phase were confirmed.

[0021] Determining the type and structure of the precipitated phase also includes:

[0022] HRTEM images of the transmission electron microscope sample are acquired, the HRTEM images containing the interface between the matrix and the precipitated phase in the observation area are magnified; Fast Fourier Transform (FFT) is performed on the HRTEM images in the observation area to obtain the corresponding FFT spots, and the FFT spots are calibrated. Combined with the chemical composition of the matrix and the precipitated phase, the type and structure of the precipitated phase are determined; the type and structure of the precipitated phase are further determined.

[0023] The region at the interface between the matrix and the precipitated phase is analyzed to obtain the strain components in different directions at the interface, thus obtaining the strain field distribution at the interface, specifically:

[0024] The acquired HRTEM image was imported into Digital Micrograph software. The region at the interface between the matrix and the precipitated phase was selected as the analysis area. Using geometric phase analysis, the ε at the interface of the analysis area was obtained. xx ε yy ε xy The strain components in three directions are used to obtain the strain field distribution at the interface.

[0025] Based on the strain components at the interface between the matrix and the precipitated phase, the strain energy at the interface is obtained; specifically:

[0026] Based on dislocation theory, ε at the interface between the matrix and the precipitated phase. xx ε yy ε xy The strain components in the three directions yield the strain energy at the interface;

[0027]

[0028] Where λ and μ are Lamé coefficients, ε ij For strain tensor;

[0029] The specific expression for the Lamé coefficient is:

[0030]

[0031]

[0032] Where E is Young's modulus and ν is Poisson's ratio.

[0033] A system for measuring the interfacial strain energy of metallic materials, comprising:

[0034] A heating module is used to heat-treat metallic materials to obtain aged samples of the metallic materials;

[0035] The processing module is used to cut and grind the aged metal material sample to obtain a transmission electron microscope sample.

[0036] The analysis and calibration module performs compositional energy dispersive spectroscopy analysis and diffraction spot calibration on the transmission electron microscope sample to determine the type and structure of the precipitated phase.

[0037] The first acquisition module is used to acquire a high-resolution image of the interface between the precipitated phase and the matrix.

[0038] The analysis module analyzes the region at the interface between the matrix and the precipitated phase based on the high-resolution image at the interface, obtains the strain components in different directions at the interface of the analysis region, and obtains the strain field distribution at the interface.

[0039] The second acquisition module acquires the strain energy at the interface based on the strain components at the interface between the matrix and the precipitated phase.

[0040] The reading module is used to read the strain energy at the interface and obtain a strain energy distribution result map at the interface.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] This invention obtains transmission electron microscopy (TEM) samples by processing metallic materials. Based on the TEM samples, the types and structures of precipitates and high-resolution images of the interfaces can be obtained; subsequently, strain field and strain energy information of the selected region can be obtained. This invention, through high-resolution images of the precipitate-matrix interface, enables comprehensive analysis of the strain distribution at the precipitate-matrix interface, improving the reliability of the tests.

[0043] Furthermore, by utilizing the phase structure information contained in HRTEM, not only can the strain field and strain energy information of the two phases in the selected region be analyzed, but the orientation relationship between the two phases can also be analyzed using Fast Fourier Transform. Attached Figure Description

[0044] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 This is a flowchart of the method for measuring the interfacial strain energy of metallic materials according to the present invention;

[0046] Figure 2 This is a system structure diagram of the present invention for measuring the interfacial strain energy of metallic materials;

[0047] Figure 3The figures show the strain field distribution inside the ferrite in a ferritic stainless steel sample held at 350℃ for 300 hours; (a) is the HRTEM image; (b) is the ε... xx Strain component diagram; (c) is ε yy Strain component diagram; (d) represents ε xy Strain component diagram; (e) shows the strain data at the location marked in figure (c);

[0048] Figure 4 The strain field distribution at the interface between ferrite and precipitated phases in ferritic stainless steel samples held at 475℃ for 1000 hours is shown in the figures; (a) is the HRTEM image; (b) is the ε... xx Strain component diagram; (c) is ε yy Strain component diagram; (d) represents ε xy Strain component diagram; (e) shows the strain data at the marked locations in diagram (d);

[0049] Figure 5 The strain energy distribution at the interface between ferrite and precipitated phase in a ferritic stainless steel sample held at 475℃ for 1000 hours is shown in Figure (a). (b) shows the strain energy distribution at the location marked in Figure (a).

[0050] Figure 6 Figure 1 shows the strain field distribution at different phase interfaces in the copper alloy sample; (a) is the HRTEM image; (b) is the ε... xx Strain component diagram; (c) is ε yy Strain component diagram; (d) represents ε xy Strain component diagram; (e) shows the strain data at the location marked in figure (c). Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0052] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0053] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0054] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0055] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0056] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0057] The present invention will now be described in further detail with reference to the accompanying drawings:

[0058] See Figure 1 This invention discloses a method for measuring the interfacial strain energy of metallic materials, comprising:

[0059] S101, heat treatment of metallic materials to obtain aged samples of metallic materials;

[0060] The metal material is heated to obtain aged samples, specifically: ferritic stainless steel is held in a box-type resistance furnace for 300 to 1000 hours at a holding temperature of 350 to 750°C to obtain aged samples containing precipitates of different sizes and types in the ferrite; or a deep-cryogenic copper alloy is held at 450 to 550°C for 1 to 5 hours to obtain aged samples with precipitates.

[0061] S102, the aged metal material sample is cut and polished to obtain a transmission electron microscope sample.

[0062] The aged samples of ferritic stainless steel or copper alloy precipitates were cut into thin slices measuring 15mm × 15mm × 0.6mm, taking care to prevent localized heat deformation during the cutting process. The slices were then successively polished with 400#, 800#, 1200#, 1500#, and 2000# metallographic sandpaper until the thickness was less than 100μm. The slices were then punched into 3mm diameter discs using a punching machine, and further polished with 2000# metallographic sandpaper to a thickness of less than 50μm. The polished slices were then subjected to thinning treatment using an electrolytic double-jet thinner or an ion thinner to obtain transmission electron microscopy (TEM) samples. The electrolytic double-jet solution consisted of 95% ethanol and 5% perchloric acid.

[0063] S103, perform energy dispersive spectroscopy analysis and diffraction spot calibration on transmission electron microscopy samples to determine the type and structure of precipitated phases.

[0064] The transmission electron microscope (TEM) sample was placed into the TEM for observation. The observation area was the thin region near the thinning aperture, which contained the matrix and precipitates. First, the TEM sample was subjected to energy dispersive spectroscopy (EDS) analysis to obtain the chemical composition of the matrix and precipitates in the observation area. Second, diffraction spots in the direction of the region were obtained, and the diffraction spots were calibrated. Combined with the chemical composition of the precipitates, the type and structure of the precipitates were confirmed.

[0065] S104, Obtain a high-resolution image of the interface between the precipitated phase and the matrix.

[0066] A high-resolution HRTEM image of the sample is acquired, which includes the interface between the matrix and the precipitated phase in the observation area. This HRTEM image is magnified to a magnification of 600,000 to 800,000 times. A fast Fourier transform (FFT) is performed on the HRTEM image in the observation area to obtain corresponding FFT spots. These FFT spots are then calibrated, and the type and structure of the precipitated phase are determined based on the chemical composition of the matrix and the precipitated phase. The type and structure of the precipitated phase are further determined. The HRTEM image is a high-resolution image; the FFT is a fast Fourier transform.

[0067] S105, based on the high-resolution image at the interface, analyzes the region at the interface between the matrix and the precipitated phase, obtains the strain components in different directions at the interface of the analysis region, and obtains the strain field distribution at the interface.

[0068] The acquired HRTEM image was imported into Digital Micrograph software. The region at the interface between the matrix and the precipitated phase was selected as the analysis area. Using geometric phase analysis, the ε at the interface of the analysis area was obtained. xx ε yy ε xyThe strain components in three directions are used to obtain the strain field distribution at the interface.

[0069] S106, based on the strain components at the interface between the matrix and the precipitated phase, obtains the strain energy at the interface.

[0070] Based on dislocation theory, ε at the interface between the matrix and the precipitated phase. xx ε yy ε xy The strain components in the three directions yield the strain energy at the interface;

[0071]

[0072] Where λ and μ are Lamé coefficients, ε ij Let be the strain tensor; i and j take the values ​​x, y, and z, respectively.

[0073] The specific expression for the Lamé coefficient is:

[0074]

[0075]

[0076] Where E is Young's modulus and ν is Poisson's ratio.

[0077] S107, Read the strain energy at the interface and obtain the strain energy distribution result map at the interface.

[0078] Using the Standard Tools in Digital Micrograph software Use the tool button to draw a line segment in the region of interest in the interface strain energy image. At the same time, the "Profile of**" image will appear. The relative magnitude of the strain energy at the interface can be read from the coordinates on the left.

[0079] See Figure 2 This invention discloses a system for measuring the interfacial strain energy of metallic materials, comprising:

[0080] A heating module is used to heat-treat metallic materials to obtain aged samples of the metallic materials;

[0081] The processing module is used to cut and grind the aged metal material sample to obtain a transmission electron microscope sample.

[0082] The analysis and calibration module performs compositional energy dispersive spectroscopy analysis and diffraction spot calibration on the transmission electron microscope sample to determine the type and structure of the precipitated phase.

[0083] The first acquisition module is used to acquire a high-resolution image of the interface between the precipitated phase and the matrix.

[0084] The analysis module analyzes the region at the interface between the matrix and the precipitated phase based on the high-resolution image at the interface, obtains the strain components in different directions at the interface of the analysis region, and obtains the strain field distribution at the interface.

[0085] The second acquisition module acquires the strain energy at the interface based on the strain components at the interface between the matrix and the precipitated phase.

[0086] The reading module is used to read the strain energy at the interface and obtain a strain energy distribution result map at the interface.

[0087] Example 1

[0088] Ferritic stainless steel was heated at 350℃ for 300 hours in a box furnace to prepare precipitated phase samples. The precipitated phase samples were cut into thin slices measuring 15mm × 15mm × 0.6mm. These slices were polished with metallographic sandpaper to a thickness of less than 100μm. The samples were then punched into circular pieces with a diameter of 3mm using a punching machine, and further polished with metallographic sandpaper to a thickness of less than 50μm. Finally, the slices were thinned using an electrolytic double-jet thinner to prepare transmission electron microscopy (TEM) samples.

[0089] The transmitted electron microscopy (TEM) sample was observed to locate the ferrite matrix region. First, compositional energy dispersive spectroscopy (EDS) analysis was performed on this region, followed by the acquisition of diffraction patterns. A high-resolution HRTEM image containing the ferrite was then acquired in high-resolution mode. Geometric phase analysis was used to analyze the strain field of the HRTEM image, obtaining the ε-strain at the interface of the analyzed region. xx ε xy ε yy The strain components in three directions yield the strain field distribution of the ferrite. For example... Figure 3 As shown.

[0090] Using dislocation theory, ferrite ε xx ε yy ε xy Substituting the strain components in the three directions into the following formula yields the strain energy distribution in the analysis region.

[0091]

[0092] Where λ and μ are Lamé coefficients, ε ij Let Lamé be the strain tensor. The specific expression for the Lamé coefficient is:

[0093]

[0094]

[0095] Where E is Young's modulus and ν is Poisson's ratio.

[0096] Using the Standard Tools in Digital Micrograph software Use the tool button to draw a line segment in the region of interest on the strain energy image. At the same time, the "Profile of**" image will appear, and the relative magnitude of the strain energy can be read from the coordinates on the left.

[0097] Example 2

[0098] Ferritic stainless steel was heated at 475℃ for 1000 hours in a box furnace to prepare precipitated phase samples. The precipitated phase samples were cut into thin slices measuring 15mm × 15mm × 0.6mm. These slices were polished with metallographic sandpaper to a thickness of less than 100μm, then punched into circular pieces with a diameter of 3mm using a punching machine, and further polished with metallographic sandpaper to a thickness of less than 50μm. The slices were then thinned using an electrolytic double-jet thinner to prepare transmission electron microscopy (TEM) samples.

[0099] The transmitted electron microscopy (TEM) sample was observed to locate the region containing the ferrite matrix and precipitated phase. First, compositional energy dispersive spectroscopy (EDS) analysis was performed on this region. Then, diffraction spots in this region were obtained, and the chemical composition of the ferrite and precipitated phase was used to confirm the type and structure of the precipitated phase.

[0100] HRTEM images of the interface containing ferrite and precipitates were acquired in high-resolution mode. Strain field analysis was performed on the HRTEM images using geometric phase analysis to obtain the ε0 at the interface of the analyzed region. xx ε xy ε yy The strain components in three directions yield the strain field distribution at the interface. For example... Figure 4 As shown.

[0101] Using dislocation theory, the ε at the interface between ferrite and precipitated phase is... xx ε yy ε xy Substituting the strain components in the three directions into the following formula, we obtain the strain energy at the interface.

[0102]

[0103] Where λ and μ are Lamé coefficients, ε ij Let Lamé be the strain tensor. The specific expression for the Lamé coefficient is:

[0104]

[0105]

[0106] Where E is Young's modulus and ν is Poisson's ratio.

[0107] Using the Standard Tools in Digital Micrograph software Using the tool button, draw a line segment across the region of interest in the interface strain energy image. Simultaneously, a "Profile of **" image will appear. The relative magnitude of the strain energy at the interface can be read from the coordinates on the left (e.g., ...). Figure 5 ).

[0108] Example 3

[0109] A precipitated phase sample was prepared by holding a cryogenically treated copper alloy at 500℃ for 3 hours. The precipitated phase sample was cut into thin slices with dimensions of 15mm × 15mm × 0.6mm. The slices were polished with metallographic sandpaper to a thickness of less than 100μm, and then punched into circular slices with a diameter of 3mm using a punching machine. These circular slices were then polished with metallographic sandpaper to a thickness of less than 50μm. The slices were then thinned using an ion thinner to prepare a transmission electron microscope (TEM) sample.

[0110] The transmitted electron microscope (TEM) was used to observe the transmitted sample and locate regions containing interfaces between different phases of the copper alloy. First, compositional energy dispersive spectroscopy (EDS) was performed on these regions. Then, diffraction patterns were obtained from these regions to confirm the types and structures of the precipitated phases by analyzing the chemical composition and diffraction patterns of the two different phases.

[0111] HRTEM images containing different phase interfaces were acquired in high-resolution mode. Strain field analysis was performed on the HRTEM images using geometric phase analysis to obtain the ε-strain at the interface of the analysis region. xx ε xy ε yy The strain components in three directions are used to obtain the strain field distribution at the interface (e.g., Figure 6 ).

[0112] Using dislocation theory, ε at different phase interfaces xx ε yy ε xy Substituting the strain components in the three directions into the following formula yields the strain energy distribution in the analysis region.

[0113]

[0114] Where λ and μ are Lamé coefficients, ε ij Let Lamé be the strain tensor. The specific expression for the Lamé coefficient is:

[0115]

[0116]

[0117] Where E is Young's modulus and ν is Poisson's ratio.

[0118] Using the Standard Tools in Digital Micrograph software Use the tool button to draw a line segment in the region of interest in the interface strain energy image. At the same time, the "Profile of**" image will appear, and the relative magnitude of the strain energy at the interface can be read from the coordinates on the left.

[0119] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for measuring the interfacial strain energy of metallic materials, characterized in that, include: Heat treatment is performed on metallic materials to obtain aged samples of the metallic materials; The aged metal material samples were cut and polished to obtain transmission electron microscope (TEM) samples. Compositional energy dispersive spectroscopy (EDS) analysis and diffraction spot identification were performed on the transmission electron microscopy (TEM) samples to determine the type and structure of the precipitated phases. Specifically: The transmission electron microscope (TEM) sample was placed in the TEM for observation. The observation area was a thin region near the thinning aperture, containing both the matrix and the precipitated phase. First, the TEM sample underwent energy dispersive spectroscopy (EDS) analysis to obtain the chemical composition of the matrix and precipitated phase within the observation area. Second, diffraction spots along the direction of the observation area were acquired, calibrated, and their type and structure confirmed based on the chemical composition of the precipitated phase. Confirmation of the precipitated phase type and structure further included: acquiring and magnifying a high-resolution TEM (High-Resolution Electron Microscopy) image of the TEM sample, which contained the interface between the matrix and the precipitated phase in the observation area; performing a fast Fourier transform (FFT) on the HRTEM image to obtain the corresponding FFT spots, calibrating these spots, and determining the type and structure of the precipitated phase based on the chemical composition of the matrix and the precipitated phase; further confirming the type and structure of the precipitated phase. Obtain a high-resolution image of the interface between the precipitated phase and the matrix; Based on the high-resolution image at the interface, the region at the interface between the matrix and the precipitated phase is analyzed to obtain the strain components in different directions at the interface, thus obtaining the strain field distribution at the interface, specifically: The acquired HRTEM image was imported into Digital Micrograph software. The region at the matrix-precipitate interface was selected as the analysis area. Geometric phase analysis was used to obtain the matrix-precipitate interface region. , , The strain components in three directions are used to obtain the strain field distribution at the interface; Based on the strain components at the interface between the matrix and the precipitated phase, the strain energy at the interface is obtained. Read the strain energy at the interface and obtain the strain energy distribution result map at the interface.

2. The method for measuring the interfacial strain energy of metallic materials according to claim 1, characterized in that, The process of heating the metal material to obtain an aged sample specifically involves: holding ferritic stainless steel in a box-type resistance furnace for 300 to 1000 hours at a temperature of 350 to 750°C to obtain an aged sample containing precipitates of different sizes and types in the ferrite; or holding a deep-cryogenic copper alloy at 450 to 550°C for 1 to 5 hours to obtain an aged sample with precipitates.

3. The method for measuring the interfacial strain energy of metallic materials according to claim 2, characterized in that, The step of cutting and polishing the aged metal material sample to obtain a transmission electron microscope (TEM) sample specifically involves: The aged metal sample was cut into thin slices of 15mm×15mm×0.6mm and polished with metallographic sandpaper until the slice thickness was less than 100μm. The slices were then punched into circular slices with a diameter of 3mm and polished again with metallographic sandpaper until the slice thickness was less than 50μm. The polished slices were then placed in an electrolytic double-jet thinner or an ion thinner for thinning treatment to obtain the transmission electron microscope sample.

4. The method for measuring the interfacial strain energy of metallic materials according to claim 1, characterized in that, The strain energy at the interface is obtained based on the strain components at the interface between the matrix and the precipitated phase; specifically: Based on dislocation theory, at the interface between the matrix and the precipitated phase , , The strain components in the three directions yield the strain energy at the interface; in, and Lamé coefficient, For strain tensor; The specific expression for the Lamé coefficient is: in, For Young's modulus, It is Poisson's ratio.

5. A system for measuring the interfacial strain energy of metallic materials, used to implement the method for measuring the interfacial strain energy of metallic materials according to any one of claims 1-4, characterized in that, include: A heating module is used to heat-treat metallic materials to obtain aged samples of the metallic materials; The processing module is used to cut and grind the aged metal material sample to obtain a transmission electron microscope sample. The analysis and calibration module performs compositional energy dispersive spectroscopy analysis and diffraction spot calibration on the transmission electron microscope sample to determine the type and structure of the precipitated phase. The first acquisition module is used to acquire a high-resolution image of the interface between the precipitated phase and the matrix. The analysis module analyzes the region at the interface between the matrix and the precipitated phase based on the high-resolution image at the interface, obtains the strain components in different directions at the interface between the matrix and the precipitated phase, and obtains the strain field distribution at the interface between the matrix and the precipitated phase. The second acquisition module acquires the strain energy at the interface based on the strain components at the interface between the matrix and the precipitated phase. The reading module is used to read the strain energy at the interface and obtain a strain energy distribution result map at the interface.

Images