CN111678932B - Analysis method of electron back scattering diffraction - Google Patents
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Abstract
The application discloses an analysis method of electron back scattering diffraction, which comprises the following steps: preparing a calibration sample according to a preset process; according to preset working parameters, carrying out Electron Back Scattering Diffraction (EBSD) analysis on the calibration sample under a scanning electron microscope, and determining a target grain boundary of the calibration sample; performing line scanning analysis on the target grain boundary by adopting a first scanning step length to obtain pattern quality BC values of the chrysanthemum pool patterns of all sampling points on the line scanning path; unimodal fitting is carried out on all BC values, and a unimodal fitting curve of the BC values is obtained; the half-width of a unimodal fitting curve is determined, and the half-width is determined as the spatial resolution of EBSD analysis of a scanning electron microscope under preset working parameters; and determining target analysis parameters when EBSD analysis is carried out on the sample to be analyzed according to the spatial resolution. The method can analyze the spatial resolution of the EBSD under the current working parameters more conveniently and rapidly, and based on the spatial resolution, the accuracy of the EBSD analysis of the sample to be analyzed is improved.
Description
Technical Field
The application relates to the technical field of metal material detection, in particular to an analysis method of electron back scattering diffraction.
Background
The electron diffraction analysis device (EBSD) is added in the scanning electron microscope, can be used for analyzing the crystallographic information of the material, and is widely applied to the microstructure and texture characterization of the metal material. The resolution of the EBSD includes spatial resolution, which is the smallest grain size that the EBSD can resolve, and angular resolution, which determines the applicable scanning step size in EBSD analysis. Generally, the spatial resolution of EBSD is mainly dependent on the beam spot size of the incident electron beam, and the larger the size of the beam spot, the smaller the spatial resolution; in addition, the spatial resolution of EBSD is also related to the atomic number of the sample, and the smaller the atomic number is, the larger the generation range of backscattered electrons is, and the resolution thereof is reduced under the same parameters. Therefore, the spatial resolution of the EBSD of the scanning electron microscope under the current working condition is determined, and based on the spatial resolution, reasonable analysis parameters are determined, so that the EBSD detection analysis of the material microstructure can be more accurately performed.
The current determination method of the spatial resolution of the EBSD is to calculate the pixel correlation of the diffraction patterns, namely, selecting a twin crystal boundary in the material, collecting the diffraction patterns at two side areas of the twin crystal boundary and collecting the reference patterns at the positions far away from the twin crystal boundary, then calculating a correlation coefficient curve between the diffraction patterns and the reference patterns by adopting a pixel correlation formula, and then calculating the spatial resolution by utilizing the correlation coefficient curve. However, computing spatial resolution using pixel correlation is complex, involving fourier transforms, gaussian filtering, and inverse fourier transforms on the correlation curves; on the other hand, twin crystal boundaries do not exist in the tissues of many metal materials or are not easy to find, so that the application difficulty of the method is increased. Therefore, a simpler and faster quantitative determination method of spatial resolution is needed, and more accurate EBSD microstructure analysis is guided by the quantitative determination method.
Disclosure of Invention
The application provides an analysis method of electron back scattering diffraction, which aims to solve or partially solve the technical problem that the accuracy of EBSD analysis is affected due to the fact that the existing determination method of the EBSD spatial resolution is too complex.
In order to solve the technical problems, the application provides an analysis method of electron back scattering diffraction, comprising the following steps:
preparing a calibration sample according to a preset process;
according to preset working parameters, carrying out Electron Back Scattering Diffraction (EBSD) analysis on the calibration sample under a scanning electron microscope, and determining a target grain boundary of the calibration sample;
performing line scanning analysis on the target grain boundary by adopting a first scanning step length to obtain pattern quality BC values of the chrysanthemum pool patterns of all sampling points on the line scanning path; the line scanning path of the line scanning analysis forms a preset angle with the target grain boundary and passes through the target grain boundary;
performing unimodal fitting on the BC values of all the sampling points to obtain a unimodal fitting curve of the BC values;
calculating the half-width of a unimodal fitting curve, and determining the half-width as the spatial resolution of EBSD analysis of a scanning electron microscope under preset working parameters;
and determining target analysis parameters when EBSD analysis is carried out on the sample to be analyzed according to the spatial resolution.
Alternatively, the predetermined angle is 90 °.
Optionally, the first scanning step is less than or equal to 50 nanometers.
Optionally, the target analysis parameter includes a second scanning step size or a target operating parameter of the scanning electron microscope.
Further, the target operating parameter includes at least one of an accelerating voltage, an electron beam current, a diaphragm aperture, and a working distance.
According to the technical scheme, according to the spatial resolution, the target analysis parameters when the EBSD analysis is carried out on the sample to be analyzed are determined, and the method specifically comprises the following steps:
when EBSD analysis is performed on the sample to be analyzed, the second scanning step is adjusted so that the second scanning step is greater than the spatial resolution.
Further, determining, according to the spatial resolution, a target analysis parameter when the EBSD analysis is performed on the sample to be analyzed, specifically including:
and when the EBSD analysis is carried out on the sample to be analyzed, adjusting the target working parameter of the scanning electron microscope so that the EBSD spatial resolution under the target working parameter is smaller than the second scanning step length.
According to the technical scheme, the calibration sample is prepared according to the preset process, and specifically comprises the following steps:
and (3) slowly polishing the surface of the selected sample by using a silica sol polishing solution, wherein the polishing speed is 100-300 rpm, and obtaining a calibration sample.
Optionally, determining a target grain boundary of the calibration sample specifically includes:
EBSD surface scanning is carried out on the local area of the calibration sample under a scanning electron microscope, and a chrysanthemum pool pattern quality BC chart of the surface scanning is obtained;
and determining a clearly imaged grain boundary from the chrysanthemum pool pattern quality BC graph as a target grain boundary.
Optionally, the selected sample is a rectangular sample with the length of 10 mm-12 mm, the width of 5 mm-8 mm and the thickness of 1 mm-2 mm; the upper and lower surfaces of the rectangular specimen are parallel to each other.
Through one or more technical schemes of the application, the application has the following beneficial effects or advantages:
the application provides an analysis method of electron back scattering diffraction, which is characterized in that line scanning is carried out on two sides of a target grain boundary in a calibration sample to obtain pattern quality BC values of chrysanthemum pool lines of all sampling points on a line scanning path, single-peak fitting is carried out on all BC values based on the principle that the minimum distance of the chrysanthemum pool lines and patterns are not overlapped is the spatial resolution, the half-width of a fitting peak is calculated, the half-width value corresponds to the spatial resolution of the EBSD under the current working parameters, and the analysis parameters of the EBSD are correspondingly adjusted according to the half-width value. The analysis method provided by the embodiment utilizes the conventional grain boundary in the material microstructure to quantitatively analyze the spatial resolution of the EBSD under the current working parameters more conveniently and rapidly, and guides the analysis parameters of the EBSD according to the spatial resolution, so that the accuracy of the EBSD analysis of the sample to be analyzed is improved.
The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:
FIG. 1 shows a flow chart of a method of analysis of electron back-scattering diffraction according to one embodiment of the application;
FIG. 2 shows an SEM photograph of the surface morphology of a sample with no visible grain boundaries for a calibration sample after slow polishing with silica sol, according to one embodiment of the application;
FIG. 3 shows a graphic representation of a pattern mass BC of a chrysanthemum pool with visible grain boundaries after a partial surface scan of a calibration sample surface, in accordance with one embodiment of the present application;
FIG. 4 shows a plot of BC values obtained by line scanning grain boundaries within the dashed box of FIG. 2 along a vertical direction thereof, in accordance with one embodiment of the present application;
FIG. 5 shows a schematic diagram of a single peak fit and half-width determination of a BC value curve in accordance with one embodiment of the application.
Detailed Description
In order to make the present application more clearly understood by those skilled in the art, the following detailed description of the technical scheme of the present application will be given by way of specific examples with reference to the accompanying drawings.
Based on the importance of accurately grasping the spatial resolution in the EBSD analysis, in an alternative embodiment, a method for determining the spatial resolution based on the quality of the pattern of the chrysanthemum pool in the EBSD analysis and performing the EBSD analysis based on the determined spatial resolution is provided, and the overall concept is as follows:
an analytical method of electron back-scattering diffraction, as shown in figure 1, comprising:
s1: preparing a calibration sample according to a preset process;
s2: according to preset working parameters, carrying out Electron Back Scattering Diffraction (EBSD) analysis on the calibration sample under a scanning electron microscope, and determining a target grain boundary of the calibration sample;
s3: performing line scanning analysis on the target grain boundary by adopting a first scanning step length to obtain pattern quality BC values of the chrysanthemum pool patterns of all sampling points on the line scanning path; the line scanning path of the line scanning analysis forms a preset angle with the target grain boundary and passes through the target grain boundary;
s4: performing unimodal fitting on the BC values of all the sampling points to obtain a unimodal fitting curve of the BC values;
s5: calculating the half-width of a unimodal fitting curve, and determining the half-width as the spatial resolution of EBSD analysis of a scanning electron microscope under preset working parameters;
s6: and determining target analysis parameters when EBSD analysis is carried out on the sample to be analyzed according to the spatial resolution.
Specifically, in the electron back scattering diffraction analysis method provided in this embodiment, firstly, tissue analysis is performed on a calibration sample under EBSD by adopting preset working parameters, a chrysanthemum pool pattern quality BC image of the calibration sample is obtained through back scattering diffraction imaging of a scanning electron microscope, and then a target grain boundary with clear imaging is determined from the chrysanthemum pool pattern quality BC image; in the scanning electron microscope, common preset working parameters include: the acceleration and pressurization of the electron beam are 15kV or 20kV, the electron beam current is 1-10 nA, the working distance WD is 13-15 mm, the aperture setting values of the diaphragm are 30 mu m, 50 mu m, 70 mu m, 110 mu m and the like; the steel sample can be selected as the calibration sample, and further, soft steel such as a low-carbon and ultra-low-carbon component system is selected, so that the soft steel has low carbon content and alloy content, is easy to prepare and facilitates the observation of clear grain boundaries in tissues;
next, performing EBSD line scanning analysis on one side of the target grain boundary according to a first scanning step length, wherein the line scanning is to determine a scanning line in a chrysanthemum pool pattern quality BC graph, sample and analyze the path of the line at intervals of the first scanning step length, the path of the line scanning starts from a crystal grain on one side of the target grain boundary, passes through the target grain boundary at a certain preset angle and extends into the crystal grain on the other side of the target grain boundary (as shown by a broken line in fig. 3), and the EBSD analyzes and outputs a chrysanthemum pool pattern and a corresponding chrysanthemum pool pattern quality BC value (or a chrysanthemum pool line contrast value) of a series of sampling points on the path;
then, common analysis software with fitting and drawing functions, such as Origin software, can be used, firstly, BC values of all sampling points are drawn into BC value curves, unimodal fitting is carried out on the BC value curves, a unimodal fitting curve is obtained, and the half-width of a fitting peak is calculated, wherein the half-width is the value of the spatial resolution of the EBSD under the current working parameters. For accuracy, the target grain boundary can be measured for three times according to the method to obtain an average value, or other target grain boundaries can be selected for analysis and then the average value is obtained;
after the EBSD spatial resolution under the current working parameters is determined, the material characteristics of the sample to be analyzed, such as a main component system of the material, the grain size and the like, can be combined, the target analysis parameters of the EBSD can be determined or adjusted adaptively, and then the detection analysis of the EBSD is carried out on the sample to be analyzed according to the target analysis parameters; the method provided by the embodiment improves the accuracy of EBSD analysis and simultaneously provides data support for the minimum microscopic scale which can be characterized by the EBSD.
It should be noted that, the determination of the spatial resolutions of S1 to S5 is not required before each detection of the sample to be analyzed, and the spatial resolution data obtained by one determination can be used for guiding multiple EBSD analyses of the same scanning electron microscope.
The principle of determining the spatial resolution using BC values obtained by EBSD line scanning provided in this embodiment is as follows: the study shows that the spatial resolution of the EBSD is equivalent to the minimum distance between two points on the sample corresponding to two chrysanthemum pool patterns which can be correctly calibrated, and the pattern quality BC value (or chrysanthemum pool line contrast value) is the imaging quality for representing the chrysanthemum pool line pattern; in the discontinuous region between two grains, that is, both sides of the grain boundary, the pattern quality BC value of the chrysanthemum pool line obtained by line scanning through the target grain boundary is significantly reduced due to the orientation difference existing between the grains, because: when the sampling points are gradually close to the grain boundary, the patterns of the chrysanthemum pools with sampling points in different orientations at the two sides of the grain boundary are mutually crossed and interfered, so that the patterns of the chrysanthemum pools with sampling points near the grain boundary become more blurred compared with those at the positions far away from the grain boundary, and the quality of the patterns of the chrysanthemum pools is obviously reduced to generate mutation; the magnitude of the current spatial resolution is determined by the breakfast and the evening generated by mutation of the mass BC value of the chrysanthemum pool pattern of sampling points on a line scanning path passing through the grain boundary along a preset angle. According to the EBSD analysis method provided by the embodiment, based on the mutation principle of the mass BC value of the chrysanthemum pool pattern of the sampling points at the two sides of the grain boundary, the fitting peak representing the BC value mutation rule of the sampling points at the two sides of the grain boundary is obtained by carrying out single-peak fitting on the BC value of the chrysanthemum pool pattern of the sampling points on the line scanning path, and then the half-width of the fitting peak is calculated, wherein the half-width value corresponds to the minimum non-overlapping distance of the chrysanthemum pool pattern of the EBSD under the current working parameters, so that the spatial resolution of the EBSD is correspondingly determined.
Optionally, the preset angle is 90 °, that is, the line scanning path is perpendicular to the target grain boundary, and extends from the grain at one side of the grain boundary to the grain at the other side of the grain boundary through the grain boundary, so that accuracy of spatial resolution can be improved, and unnecessary errors are avoided.
Optionally, the first scanning step length is less than or equal to 50 nanometers and nm, so as to ensure the density of sampling points on an online scanning path, improve the accuracy of the spatial resolution of the measurement, and the preferred first scanning step length is within 20 nm.
The embodiment provides an analysis method of electron back scattering diffraction, which is characterized in that line scanning is carried out on two sides of a target grain boundary in a calibration sample to obtain pattern quality BC values of chrysanthemum pool lines of all sampling points on a line scanning path, single-peak fitting is carried out on all BC values based on the principle that the minimum distance of the chrysanthemum pool lines and patterns are not overlapped is the spatial resolution, the half-width of a fitting peak is calculated, the half-width value corresponds to the spatial resolution of the EBSD under the current working parameters, and the analysis parameters of the EBSD are correspondingly adjusted according to the half-width value. The analysis method provided by the embodiment utilizes the conventional grain boundary in the material microstructure to quantitatively analyze the spatial resolution of the EBSD under the current working parameters more conveniently and rapidly, and guides the analysis parameters of the EBSD according to the spatial resolution, so that the accuracy of the EBSD analysis of the sample to be analyzed is improved.
After accurately knowing the spatial resolution of the EBSD under the current preset working parameters, the target analysis parameters adopted when the EBSD analysis is performed on the sample to be analyzed can be guided and determined from two aspects. In another alternative embodiment, the target analysis parameters include a second scan step size or a target operating parameter of the scanning electron microscope based on the same inventive concept as the previous embodiment. The second scanning step length refers to a scanning step length range which should be adopted when EBSD line scanning or surface scanning is carried out on the sample to be analyzed; the target working parameters refer to the specific range of the working parameters which should be set by the scanning electron microscope when the EBSD analysis is carried out on the sample to be analyzed. As previously mentioned, the spatial resolution of EBSD is primarily dependent on the beam spot size of the incident electron beam; meanwhile, the working parameters of a scanning electron microscope, such as the adopted accelerating voltage, aperture of a diaphragm, beam current of an electron beam and the like, have obvious influence on the spatial resolution of the EBSD during the EBSD analysis. Thus, the target operating parameters include at least one of acceleration voltage, electron beam current, diaphragm aperture, working distance.
Optionally, determining, according to the spatial resolution, a target analysis parameter when the EBSD analysis is performed on the sample to be analyzed, specifically includes: when EBSD analysis is performed on the sample to be analyzed, the second scanning step is adjusted so that the second scanning step is greater than the spatial resolution. That is, the spatial resolution can be used to guide the minimum scan step of line and surface scanning in EBSD analysis, and a scan step smaller than the current spatial resolution has no sense of detection and only increases unnecessary analysis time.
In some cases, a scanning step with smaller spatial resolution than the current preset working parameter is needed, for example, a material sample with smaller atomic number of the main component element is detected, and a higher spatial resolution is needed, at this time, the spatial resolution of the EBSD can be improved by adjusting the working parameter of the EBSD, so that the value of the spatial resolution is reduced below the second scanning step. Optionally, determining, according to the spatial resolution, a target analysis parameter when the EBSD analysis is performed on the sample to be analyzed, specifically includes: and when the EBSD analysis is carried out on the sample to be analyzed, adjusting the target working parameter of the scanning electron microscope so that the EBSD spatial resolution under the target working parameter is smaller than the second scanning step length. For example, reasonable collocation of working parameters such as properly reducing accelerating voltage, reducing electron beam current, reducing aperture of diaphragm, shortening working distance and the like can be adopted, and the spatial resolution of the EBSD is improved. For example, the spatial resolution of the EBSD is improved by reducing the acceleration voltage from 15kv to 12kv, the electron beam current from 5nA to 2nA, the diaphragm aperture from 50 micrometers to 30 micrometers, and the working distance from 15mm to 13mm, singly or in combination.
The selection and preparation of the calibration sample is important for accurately determining the spatial resolution, and the grain boundary relief effect of the material is an important factor affecting the accurate determination of the spatial resolution. In order to eliminate the adverse effect of grain boundary relief effects on spatial resolution, based on the same inventive concept as in the previous embodiment, in a further alternative embodiment, a calibration sample is prepared according to a preset process, specifically comprising: and (3) slowly polishing the surface of the selected sample by using a silica sol polishing solution, wherein the polishing speed is 100-300 rpm, and obtaining a calibration sample.
The conventional sample polishing method and polishing solution cannot eliminate the embossments near the grain boundaries of the materials, in the embodiment, the silica sol polishing solution is adopted to polish the selected samples or the samples to be calibrated at a low speed, so that the residual stress of the materials can be removed, more importantly, the surface embossments of the grain boundaries can be eliminated, the phenomenon that the measuring result of the spatial resolution is large due to the embossment effect is avoided, and the accuracy of the measuring result of the spatial resolution is improved.
Since the silica sol polishing solution is used for polishing at a low speed, the surface of the calibration sample is likely to be incapable of clearly identifying the grain boundary under the scanning electron microscope, and in order to solve the problem, the method for determining the target grain boundary of the calibration sample specifically comprises the following steps: EBSD surface scanning is carried out on the local area of the calibration sample under a scanning electron microscope, and a chrysanthemum pool pattern quality BC chart of the surface scanning is obtained; and determining a clearly imaged grain boundary from the chrysanthemum pool pattern quality BC graph as a target grain boundary.
For the shape specification of the sample, the selected sample is a rectangular sample with the length of 10 mm-12 mm, the width of 5 mm-8 mm and the thickness of 1 mm-2 mm; the upper and lower surfaces of the rectangular specimen are parallel to each other.
In the following embodiment, the scheme in the above embodiment is described in detail with specific data:
in the embodiment, the ultra-low carbon IF steel is used as a calibration sample, and the spatial resolution of the EBSD is measured, and the steps are as follows:
(1) Preparing a calibration sample: the sample size is required to be 10mm in length, 5mm in width and 1mm in thickness, the upper surface and the lower surface are guaranteed to be parallel, in order to eliminate the influence of grain boundary relief effect on a resolution measurement result during online scanning, the sample is prepared by slowly polishing silica sol, the silica sol is made of water-soluble silicon dioxide, and the polishing rate is 150 revolutions per minute;
(2) Determining preset working parameters of a scanning electron microscope: accelerating and pressurizing by 15kV, wherein the beam current is 2nA, the working distance WD is 15mm, and the aperture of the diaphragm is 30 mu m;
(3) Determining the spatial resolution under the current working parameters: because the grain boundary of the sample surface obtained by slowly polishing the silica sol is not clear (see fig. 2), the EBSD surface scanning analysis is needed to be carried out on a local area to obtain a chrysanthemum pool pattern quality BC diagram (see fig. 3) of the local area, a proper grain boundary is found in the obtained back scattering diffraction image to serve as a target grain boundary (positioned in a dotted line frame of fig. 3), then line scanning is carried out on one side of the grain boundary along the vertical direction of the grain boundary (see a black dotted line in fig. 3), the first scanning step length of the line scanning is 3.5nm, the first scanning step length passes through the grain boundary to the other side to obtain the chrysanthemum pool pattern of each sampling point on the line scanning path, a single peak curve is drawn according to the pattern quality BC value of the chrysanthemum pool pattern (see fig. 4), then the single peak fitting is carried out by using Origin professional software, the corresponding half-height width is calculated (see fig. 5), the average value is measured three times on the same grain boundary according to the method, and the average value is shown in the following table 1 under the current condition;
TABLE 1 half-width statistics of three measurements of the same grain boundary
(4) Determining target analysis parameters of the EBSD: after determining that the EBSD spatial resolution under the current working parameter is 51.7nm, if the working parameter of the scanning electron microscope is not changed, when the EBSD is carried out on the sample to be analyzed subsequently, the second scanning step length of the surface scanning and the line scanning needs to be controlled to be more than 52 nm; if a scanning step of less than 50nm, such as about 40nm, is needed for a certain analysis sample, the working parameters of the electron microscope should be adjusted at this time, so as to improve the spatial resolution of the EBSD and reduce the numerical value of the spatial resolution to less than 40 nm.
Through one or more embodiments of the present application, the present application has the following benefits or advantages:
the application provides an analysis method of electron back scattering diffraction, which is characterized in that line scanning is carried out on two sides of a target grain boundary in a calibration sample to obtain pattern quality BC values of chrysanthemum pool lines of all sampling points on a line scanning path, single-peak fitting is carried out on all BC values based on the principle that the minimum distance of the chrysanthemum pool lines and patterns are not overlapped is the spatial resolution, the half-width of a fitting peak is calculated, the half-width value corresponds to the spatial resolution of the EBSD under the current working parameters, and the analysis parameters of the EBSD are correspondingly adjusted according to the half-width value. The analysis method provided by the embodiment utilizes the conventional grain boundary in the material microstructure to quantitatively analyze the spatial resolution of the EBSD under the current working parameters more conveniently and rapidly, and guides the analysis parameters of the EBSD according to the spatial resolution, so that the accuracy of the EBSD analysis of the sample to be analyzed is improved.
While preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the application.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present application without departing from the spirit or scope of the application. Thus, it is intended that the present application also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (10)
1. A method of analyzing electron back-scattering diffraction, the method comprising:
preparing a calibration sample according to a preset process;
according to preset working parameters, carrying out Electron Back Scattering Diffraction (EBSD) analysis on the calibration sample under a scanning electron microscope, and determining a target grain boundary of the calibration sample;
performing line scanning analysis on the target grain boundary by adopting a first scanning step length to obtain pattern quality BC values of chrysanthemum pool patterns of all sampling points on an online scanning path; the line scanning path of the line scanning analysis forms a preset angle with the target grain boundary and passes through the target grain boundary; the line scan analysis includes: determining a scanning line in a chrysanthemum pool pattern mass BC chart, sampling and analyzing on the path of the scanning line by taking the first scanning step length as an interval, wherein the path of line scanning starts from a crystal grain at one side of the target crystal boundary, passes through the target crystal boundary at the preset angle and extends into the crystal grain at the other side of the target crystal boundary;
performing unimodal fitting on the BC values of all the sampling points to obtain a unimodal fitting curve of the BC values;
calculating the half-width of the unimodal fitting curve, and determining the half-width as the spatial resolution of EBSD analysis of the scanning electron microscope under the preset working parameters;
and determining target analysis parameters when EBSD analysis is carried out on the sample to be analyzed according to the spatial resolution.
2. The method of analysis according to claim 1, wherein the predetermined angle is 90 °.
3. The method of analysis of claim 1, wherein the first scanning step size is 50 nanometers or less.
4. The method of analysis of claim 1, wherein the target analysis parameter comprises a second scan step size or a target operating parameter of the scanning electron microscope.
5. The method of analysis of claim 4, wherein the target operating parameter comprises at least one of an acceleration voltage, an electron beam current, a diaphragm aperture, and a working distance.
6. The analysis method according to claim 4, wherein determining the target analysis parameters for EBSD analysis of the sample to be analyzed based on the spatial resolution comprises:
and when the EBSD analysis is performed on the sample to be analyzed, adjusting the second scanning step length so that the second scanning step length is larger than the spatial resolution.
7. The analysis method according to claim 5, wherein determining the target analysis parameters for EBSD analysis of the sample to be analyzed based on the spatial resolution comprises:
and when the EBSD analysis is carried out on the sample to be analyzed, adjusting the target working parameter of the scanning electron microscope so that the EBSD spatial resolution under the target working parameter is smaller than the second scanning step length.
8. The analytical method according to any one of claims 1 to 7, wherein preparing the calibration sample according to a predetermined process comprises:
and (3) slowly polishing the surface of the selected sample by using a silica sol polishing solution, wherein the polishing speed is 100-300 rpm, and obtaining a calibration sample.
9. The analytical method of claim 8, wherein said determining target grain boundaries of said calibration sample comprises:
performing EBSD surface scanning on the local area of the calibration sample under a scanning electron microscope to obtain a chrysanthemum pool pattern mass BC diagram;
and determining a clearly imaged grain boundary from the chrysanthemum pool pattern quality BC diagram as a target grain boundary.
10. The analytical method according to claim 8, wherein the selected sample is a rectangular sample having a length of 10mm to 12mm, a width of 5mm to 8mm, and a thickness of 1mm to 2 mm; the upper and lower surfaces of the rectangular sample are parallel to each other.
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