CN114441580A - Identification method of non-metal inclusion phase - Google Patents

Abstract

The application relates to the field of metal material detection, in particular to a method for identifying a non-metal inclusion phase; the method comprises the following steps: obtaining a steel sample to be tested; pre-cleaning and pre-grinding a steel sample to be detected, and then polishing to obtain a treatment sample containing impurities; collecting interested inclusions in the processed sample by an electron microscope image, and then carrying out energy spectrum component analysis and chrysanthemum pool pattern collection to respectively obtain the chemical composition of the inclusions and the chrysanthemum pool pattern to be detected; obtaining a standard chemical phase according to the chemical composition; obtaining the matching degree between the chemical composition phase and the chrysanthemum pool pattern to be detected according to the standard chemical phase and the chrysanthemum pool pattern to be detected; obtaining the phase type of the inclusions according to the matching degree; the method comprises the steps of pre-grinding a steel sample to be detected, polishing, scanning by an electron microscope, analyzing energy spectrum components and collecting chrysanthemum pool patterns, and then determining the matching degree between the chrysanthemum pool patterns to be detected and chemical composition phases, so that the phase types of inclusions can be accurately obtained, and the identification process is simplified.

Description

A kind of identification method of non-metallic inclusion phase

technical field

The present application relates to the field of metal material detection, and in particular, to a method for identifying a non-metallic inclusion phase.

Background technique

The type, shape, size and distribution of non-metallic inclusions in steel have an important impact on the properties of steel. The detection, analysis and control technology of inclusions has always been highly valued by researchers in the fields of metallurgy and materials. The conventional physical method for the characterization of non-metallic inclusions in steel is mainly to observe the morphology of the inclusions with a metallographic microscope or a scanning electron microscope, and analyze the composition of the inclusions with an energy dispersive spectrometer.

At present, the identification methods of inclusions mainly include X-ray diffraction (XRD) analysis and transmission electron microscopy selected area electron diffraction (SAD) analysis, which have the following two shortcomings:

(1) XRD analysis needs to extract a sufficient amount of inclusion particles for analysis by large sample electrolysis or small sample electrolysis. The sample preparation process is complicated, and the phase composition of the inclusions in the sample can be obtained, but the morphological information of the corresponding inclusions cannot be obtained at the same time. .

(2) The sample preparation process for SAD analysis is very complex, including dispersed crystal method, extraction replica method, metal thin film method, focused ion beam (FIB) method, etc., and the inclusions that can be detected according to the sample preparation method have particle size requirements .

To sum up, the current phase identification methods for inclusions are not mature enough, and the phase identification of inclusions is difficult. Therefore, how to provide a simple method for the identification of inclusion phases is a technical problem that needs to be solved urgently.

SUMMARY OF THE INVENTION

The present application provides a method for identifying a non-metallic inclusion phase, so as to solve the technical problem of difficulty in identifying the inclusion phase in the prior art.

In a first aspect, the present application provides a method for identifying a non-metallic inclusion phase, the method comprising:

Obtain the steel sample to be tested;

Pre-cleaning and pre-grinding the steel sample to be tested, and then polishing to obtain a treated sample containing inclusions;

Carrying out electron microscope image collection on the inclusions in the treated sample, and then performing energy spectrum component analysis and collection of the Kikuchi pattern, to obtain the chemical composition of the inclusions and the Kikuchi pattern to be tested, respectively;

According to the chemical composition, a standard chemical phase is obtained;

According to the standard chemical phase and the kikuchi pattern to be tested, obtain the matching degree between the chemical composition phase and the kikuchi pattern to be tested;

According to the matching degree, the phase type of the inclusions is obtained.

Optionally, according to the standard chemical phase and the kikuchi pattern to be tested, the matching degree between the chemical composition phase and the kikuchi pattern to be tested is obtained, specifically including:

Obtain the detection angle between the number of the kikuchi bands of the kikuchi pattern to be tested and the kikuchi band to be tested;

Obtain the standard Kikuchi band number of the standard chemical phase and the standard angle between the standard Kikuchi bands;

According to the number of the Kikuchi bands to be tested and the number of the standard Kikuchi bands, obtain the same number of Kikuchi bands between the Kikuchi pattern to be tested and the standard chemical phase;

According to the detection angle and the standard angle, the deviation of the detection angle between each pair of the Kikuchi belts to be tested and the standard angle between the corresponding standard Kikuchi belts is obtained respectively, and then the average value is taken to obtain the Kikuchi to be measured. Average angular deviation between pattern and standard chemical phase;

According to the same number of the Kikuchi bands and the average angular deviation, the matching degree between the chemical composition phase and the Kikuchi pattern to be tested is obtained.

Optionally, the matching degree is judged as follows: when the number of the same Kikuchi belts is larger and the average angle deviation is smaller, the matching degree is higher.

Optionally, the obtaining the phase type of the inclusions according to the matching degree specifically includes:

According to the matching degree, determine whether the inclusion is a single inclusion;

If so, sieve the Kikuchi pattern to be tested according to the standard chemical phase to obtain the phase type of the inclusions;

If not, the processed sample is subjected to component surface distribution analysis to obtain the surface distribution information of the components, and then the phase types of the inclusions are obtained according to the surface distribution information of the components and the standard chemical phase.

Optionally, the pre-grinding includes coarse grinding and fine grinding, both of which are ground with water sandpaper.

Optionally, the mesh number of the coarse grinding is 100#～200#, and the mesh number of the fine grinding is 750#～850#.

Optionally, the polishing includes a first polishing and a second polishing in sequence, and the first polishing includes: multiple polishings performed by using diamonds of different particle sizes as polishing agents and velvet as polishing cloths;

The second polishing includes: polishing with silica sol as polishing agent and porous neoprene as polishing cloth.

Optionally, the rotational speed of the first polishing is 900 rpm to 1500 rpm, and the time of the first polishing is 5 min to 15 min.

Optionally, the rotation speed of the second polishing is 100 rpm to 150 rpm, and the time of the second polishing is 10 min to 15 min.

Optionally, the particle size of the diamond is 0.5 μm˜7 μm.

Compared with the prior art, the above-mentioned technical solutions provided in the embodiments of the present application have the following advantages:

A method for identifying a phase of non-metallic inclusions provided by the embodiment of the present application, by pre-grinding and polishing the steel sample to be tested, to simplify the sample preparation process, and then scanning with an electron microscope to perform energy spectrum composition analysis and analysis of the electron microscope image of the inclusions The Kikuchi pattern is collected, so that the standard chemical composition phase can be deduced according to the chemical composition obtained by the energy spectrum composition analysis, and then through the matching degree between the Kikuchi pattern to be tested and the chemical composition phase, the inclusions can be accurately obtained. phase types, simplify the identification process, and then realize the simple and convenient identification of inclusions.

Description of drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description serve to explain the principles of the invention.

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. In other words, on the premise of no creative labor, other drawings can also be obtained from these drawings.

1 is a schematic flowchart of a method provided by an embodiment of the present application;

2 is a detailed schematic flowchart of a method provided by an embodiment of the present application;

3 is a morphological diagram of inclusions in the steel sample to be tested provided in Example 1 of the present application;

FIG. 4 is an analysis diagram of the energy spectrum composition of the inclusions in the steel sample to be tested provided in Example 1 of the present application;

5 is an electron backscatter diffraction Kikuchi pattern diagram of inclusions in the steel sample to be tested provided in Example 1 of the application;

6 is a matching diagram of the Kikuchi pattern of the Alabandite phase and inclusions provided in Example 1 of the present application;

7 is a matching diagram of the Kikuchi pattern of MnS phase and inclusions provided in Example 1 of the present application;

8 is a morphological diagram of inclusions in the steel sample to be tested provided in Example 2 of the present application;

Fig. 9 is the energy spectrum composition analysis diagram of the inclusion position 1 in the steel sample to be tested provided in Example 2 of this application;

Fig. 10 is the electron backscatter diffraction Kikuchi pattern diagram of the inclusion position 1 in the steel sample to be tested provided in Example 2 of the application;

11 is an analysis diagram of the energy spectrum composition of the inclusion position 2 in the steel sample to be tested provided in Example 2 of the application;

Fig. 12 is the electron backscatter diffraction Kikuchi pattern diagram of the inclusion position 2 in the steel sample to be tested provided in Example 2 of the application;

FIG. 13 is a composition plane distribution diagram of inclusions in the steel sample to be tested provided in Example 2 of the application.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

The creative idea of the present application is: because the sample preparation process of SAD analysis is very complicated, there are dispersed crystal method, extraction replica method, metal thin film method, focused ion beam (FIB) method, etc., specifically:

(1) The dispersing crystal method is to dissolve the inclusions extracted by electrolysis in an organic solution, and after ultrasonic oscillation, disperse them on a conductive support film for transmission electron microscopy observation.

(2) The extraction replica method is to remove the film after the polished metallographic sample is subjected to primary corrosion, carbon spraying, and secondary corrosion, and finally the carbon film with inclusions and organizational characteristics is fished on the supporting copper mesh for transmission. Electron microscope observation.

Since neither the dispersed crystal method nor the extraction replica method can thin the inclusions, they are only suitable for nano-scale inclusions. Therefore, for micron-scale inclusions, the metal thin film method and the focused ion beam (FIB) method can be used. The metal thin film method bombards the steel sheet and the inclusions with Ar ions at the same time to achieve the purpose of thinning the inclusions, but this method In the process of thinning the steel sheet to hundreds of nanometers or even a few nanometers, the inclusions are easy to fall off, and the number of observable inclusions is extremely limited. In-situ cross-section processing, cutting the cross-section slices of inclusions, and then using transmission electron microscopy to observe and analyze to determine the phase composition, but this method can only cut and prepare one or two inclusions at a time, and FIB equipment is extremely expensive and difficult to popularize.

There are related technologies that use ion thinning technology to prepare samples, and then use electron backscatter diffractometer (EBSD) to analyze the phase composition of inclusions under a scanning electron microscope, but this method is also only suitable for thinning of one or two inclusions. The analysis efficiency is low. In the process of ion thinning, the valence bond structure and surface hardness of different phases inside the composite inclusions are different. During the bombardment of Ar ions, the thickness of the inclusions will be uneven, which will affect the phase. Accuracy of identification.

To sum up, the above methods are either difficult to prepare samples, or the means of the detection stage are more complicated, which affects the accuracy of identification.

In an embodiment of the present application, as shown in FIG. 1 , a method for identifying a non-metallic inclusion phase is provided, and the method includes:

S1. Obtain the steel sample to be tested;

S2. Pre-cleaning and pre-grinding the steel sample to be tested, and then polishing to obtain a treated sample containing inclusions;

S3. Carry out electron microscope image collection on the inclusions in the treated sample, and then perform energy spectrum component analysis and Kikuchi pattern collection to obtain the chemical composition of the inclusions and the Kikuchi pattern to be tested, respectively, wherein the inclusions may be relative to the detection Inclusions of interest to personnel;

S4. According to the chemical composition, a standard chemical phase is obtained;

S5. according to the standard chemical phase and the kikuchi pattern to be tested, obtain the matching degree between the chemical composition phase and the kikuchi pattern to be tested;

S6. Obtain the phase type of the inclusions according to the matching degree.

In some optional embodiments, as shown in FIG. 2 , according to the standard chemical phase and the kikuchi pattern to be tested, the matching between the chemical composition phase and the kikuchi pattern to be tested is obtained degrees, including:

S51. respectively obtain the detection angle between the number of the kikuchi bands of the kikuchi pattern to be tested and the kikuchi band to be tested;

S52. respectively obtain the standard angle between the standard Kikuchi band number of the standard chemical phase and the standard Kikuchi band;

S53. according to the number of the kikuchi band to be tested and the number of the standard kikuchi band, obtain the same number of kikuchi band between the pattern of the kikuchi to be tested and the standard chemical phase;

S54. According to the detection angle and the standard angle, obtain respectively the deviation of the standard angle between the detection angle between each pair of the Kikuchi belts to be measured and the corresponding standard Kikuchi belts, and then take the average value to obtain the deviation of the standard angle between the Kikuchi belts to be measured and the corresponding standard Kikuchi belts. Measure the average angular deviation between the Kikuchi pattern and the standard chemical phase;

S55. According to the same number of the Kikuchi bands and the average angular deviation, obtain the matching degree between the chemical composition phase and the Kikuchi pattern to be tested.

In this application, by comparing the angle between the number of Kikuchi bands and the angle between the Kikuchi bands in the chemical phase and the angle between the number of Kikuchi bands and the angle between the Kikuchi bands in the Kikuchi pattern to be tested, on the basis of accurate sample preparation, the Accurately analyze the difference between the Kikuchi pattern of the sample to be tested and the standard chemical phase, so that the Kikuchi pattern can be accurately analyzed.

In some optional embodiments, the matching degree is judged as follows: when the number of the same Kikuchi belts is larger and the average angle deviation is smaller, the matching degree is higher.

In this application, the number of Kikuchi bands can fully reflect the phase distribution of the inclusions, and the average angle deviation can reflect the deviation difference between the actual sample to be tested and the phase in the standard database, so that the matching degree can be comprehensively analyzed, and then comprehensive Analyze the chemical phase and the pattern of the Kikuchi to be tested, and accurately analyze the types of inclusions.

In some optional embodiments, the obtaining the phase type of the inclusions according to the matching degree specifically includes:

S61. According to the matching degree, determine whether the inclusion is a single inclusion;

If so, sieve the Kikuchi pattern to be tested according to the standard chemical phase to obtain the phase type of the inclusions;

If not, the treated sample is subjected to component surface distribution analysis to obtain the surface distribution information of the components, and then the phase types of the inclusions are obtained according to the surface distribution information of the components and the standard chemical phase; wherein, in order to For further accurate judgment, on the basis of the matching degree, it is also necessary to increase the shape of the inclusion, and comprehensively determine whether the inclusion is a single inclusion by combining the matching degree and the shape of the inclusion.

In this application, by first analyzing the matching degree, when it is determined to be a single inclusion, only the standard chemical phase is used to screen out the similar pattern of the Kikuchi to be tested, so as to easily obtain the accurate type of inclusions. When it is determined to be a complex inclusion, by introducing the surface distribution information of the components, the standard chemical phases are combined to conduct scientific screening of multiple phases with the same matching degree, and then accurate identification results of inclusion phases can be obtained.

In some optional embodiments, the pre-grinding includes coarse grinding and fine grinding, both of which are ground with water sandpaper.

In some optional embodiments, the mesh number of the coarse grinding is 100#～200#, and the mesh number of the fine grinding is 750#～850#.

In this application, the pre-grinding is defined to include rough grinding and fine grinding, so that the surface of the sample can be ground flat in the early stage of sample preparation, the surface impurities and the processing deformation layer can be removed, and the inclusions in the sample can be exposed. Accuracy of subsequent detection.

The positive effect of rough grinding with a mesh number of 100# to 200# is that within this mesh number range, the surface of the steel product can be ground flat and surface debris can be removed; when the mesh number is greater than the maximum value of the endpoint , the adverse effect will be that the rough grinding is too fine, it is difficult to grind the surface of the sample flat, and the large debris is difficult to remove, which will affect the subsequent determination; when the value of the mesh number is less than the minimum value of the endpoint of the range, the adverse effect will be caused It is the coarse grinding that is too coarse, which affects the subsequent fine grinding stage.

The positive effect of fine grinding with a mesh number of 750# to 850# is that within this mesh number range, the deep rough grinding scratches and surface processing deformation layers on the surface of the sample can be removed, so as to facilitate subsequent polishing; If the value of is larger than the maximum value of the end point of this range, the adverse effect will be that the mesh number of fine grinding is too fine, which will affect the removal of coarse wear scars and deformation layers, and then affect the subsequent detection and analysis of inclusions; when the value of the mesh number is less than The minimum value of the endpoint of this range will lead to the adverse effect that the mesh number of fine grinding is too coarse, resulting in coarse fine grinding scratches and surface deformation layers, which will affect the subsequent polishing treatment and the detection and analysis of inclusions.

In some optional embodiments, the polishing includes a first polishing and a second polishing in sequence, and the first polishing includes: using diamonds of different particle sizes as polishing agents and velvet as polishing cloth for multiple times polishing;

The second polishing includes: polishing with silica sol as a polishing agent and porous neoprene as a polishing cloth, wherein the silica sol is obtained by passing a SiO ₂ suspension with a particle size of 0.02 μmn and deionized water according to the method. 1:1 mass ratio mixed.

In this application, by first polishing with diamond for many times, the pre-grinding scratches and deformation layers of the detection surface of the sample to be tested and the inclusions therein are removed, and then the second polishing is performed with silica sol, and the slow polishing with silica sol can be used. Effectively remove the surface stress of the conventional metallographically polished sample matrix and internal inclusions, and obtain a flat inclusion analysis surface, realizing the clear display of the Kikuchi pattern.

In some optional embodiments, the rotational speed of the first polishing is 900 rpm to 1500 rpm, and the time of the first polishing is 5 min to 15 min.

In the present application, the positive effect of the rotation speed of the first polishing being 900 rpm to 1500 rpm is that within the range of this rotation speed, the diamond can fully polish the pre-ground steel sample to be tested, thereby removing the detection surface of the sample and the fine particles of the inclusions therein. Wear scars and deformation layers can reduce the deformation stress of inclusions and facilitate the subsequent second polishing; when the value of the rotational speed is greater than the maximum value at the end of the range, the adverse effect will be that the excessively fast rotational speed will lead to partial inclusions. The phase wears out, and a large deformation stress remains, which affects the accuracy of subsequent measurements. When the value of the rotational speed is less than the minimum value of the end point of the range, the adverse effect will be that the too slow rotational speed will cause the exposed surface of the inclusions to not be damaged. leveling, which affects subsequent analysis and detection.

The positive effect of the first polishing time of 5min to 15min is that within this time range, the diamond can fully polish the pre-grinded steel sample to be tested, thereby removing the fine wear marks and deformation of the sample detection surface and the inclusions therein. layer to reduce the deformation stress of inclusions and facilitate the subsequent second polishing; when the value of time is greater than the maximum value of the endpoint of the range, the adverse effect will be to prolong the process time, and when the value of time is less than this range The minimum value of the endpoint will lead to the adverse effect that the too short polishing time will lead to the inexhaustible removal of the fine wear marks and deformation layer of the test surface of the sample and the inclusions in it, and the deformation stress of the inclusions will be large, which will affect the subsequent second polishing. conduct.

In some optional embodiments, the rotational speed of the second polishing is 100 rpm to 150 rpm, and the time of the second polishing is 10 min to 15 min.

In this application, the positive effect of the second polishing speed being 100rpm to 150rpm is that within the range of this speed, the silica sol can fully polish the pre-ground steel sample to be tested, and can effectively remove the conventional metallographic polishing sample matrix and Surface stress of internal inclusions, and obtain a flat inclusion analysis surface, so that subsequent inclusions Kikuchi patterns can be clearly displayed; when the value of the rotational speed is greater than the maximum value of the end point of the range, the adverse effect will be that the excessively fast rotational speed will It will lead to a large residual surface stress, which will affect the subsequent analysis and detection. When the value of the rotation speed is less than the minimum value of the end point of the range, the adverse effect will be that the excessive rotation speed will cause the exposed surface of the inclusions to be uneven, which will affect the subsequent inclusions. Clear display of Kikuchi patterns.

The positive effect of the second polishing time of 10min-15min is that within this time range, the silica sol can fully polish the steel sample to be tested after pre-grinding, and can effectively remove the conventional metallographic polishing sample matrix and internal inclusions. surface stress, and obtain a flat inclusion analysis surface, so that the subsequent inclusion Kikuchi pattern can be clearly displayed; when the value of time is greater than the maximum value of the end point of the range, the adverse effect will be to prolong the process time, when the time If the value is less than the minimum value of the endpoint of this range, the adverse effect will be that too short polishing time will lead to the incomplete removal of the surface stress of the inclusions, which will affect the clear display of the subsequent inclusions Kikuchi pattern.

In some optional embodiments, the particle size of the diamond is 0.5 μm˜7 μm.

In this application, the positive effect of diamond with a particle size of 0.5 μm to 7 μm is that within this particle size range, the diamond can fully grind and polish the pre-ground sample to be tested, and remove the detection surface of the sample and the fine particles of the inclusions therein. Wear scars and deformation layers reduce the deformation stress of inclusions and facilitate the subsequent second polishing; when the value of the particle size is greater than the maximum value at the end of the range, the adverse effect will be that the diamond particle size is too large, resulting in the first The polishing surface of the polishing stage is relatively rough, which affects the progress of the second polishing. When the value of the particle size is less than the minimum value of the end point of the range, the adverse effect will be that the particle size of the diamond is too small, and it is difficult to remove the particles generated in the pre-grinding stage. Wear scars and deformed layers increase time-consuming and affect the subsequent second polishing.

Example 1

As shown in Figure 2, a method for identifying a non-metallic inclusion phase includes:

S1. Cut a steel sample with a size of 20mm (length) × 7mm (width) × 10mm (height) to obtain a steel sample to be tested;

S2. Clean and pre-grind the steel sample to be tested, and then polish it to obtain a treated sample containing inclusions;

S3. Carry out electron microscope image collection on the inclusions of interest in the treated sample to obtain the pattern of the inclusions as shown in Figure 3, and then perform energy spectrum component analysis and Kikuchi pattern collection, respectively, as shown in Figure 4. The chemical composition of the inclusions and the tested Kikuchi pattern of the first inclusion as shown in Figure 5 show that the inclusions contain S, Mn, and Fe elements;

S4. According to the chemical composition, standard chemical phases Alabandite phase and MnS phase are obtained;

S51. Respectively obtain the number of kikuchi bands of the kikuchi pattern to be tested and the detection angle between the kikuchi bands to be tested;

S52. Respectively obtain the number of standard Kikuchi bands of the standard chemical phase and the standard angle between the standard Kikuchi bands;

S53. According to the number of Kikuchi bands to be tested and the number of standard Kikuchi bands, obtain the same number of Kikuchi bands between the Kikuchi pattern to be tested and the standard chemical phase;

S54. According to the detection angle and the standard angle, obtain the deviation of the detection angle between each Kikuchi band to be tested and the standard angle between the corresponding standard Kikuchi band, and then take the average value to obtain the Kikuchi pattern to be tested and the standard chemical substance mean angular deviation between phases;

Alabandite相

因此根据相同的菊池带数计算，Alabandite相与夹杂物的菊池花样的匹配带数较多，匹配度较高；S55. Obtain the matching degree between the chemical composition phase and the Kikuchi pattern to be tested according to the same number of Kikuchi bands and the average angular deviation, wherein, as shown in Figure 6, the same number of Kikuchi bands of the standard chemical phase Alabandite phase is 12, the average angular deviation is 0.31, and as shown in Figure 7, the number of identical Kikuchi bands of the standard chemical phase MnS phase is 8, and the average angular deviation is 0.25, although the element composition and content of the MnS phase and the Alabandite phase are the same, In terms of mass fraction, both are S: 50%, Mn: 50%, but the crystal structures of the two are different, the MnS phase unit cell

Alabandite Phase

Therefore, according to the calculation of the same number of Kikuchi bands, the number of matching bands between Alabandite phase and the Kikuchi pattern of inclusions is higher, and the matching degree is higher;

S61. According to the degree of matching and the shape of the inclusion, determine that the inclusion is a single inclusion;

The Kikuchi pattern to be tested was sieved according to the standard chemical phase, and the phase type of the inclusions was obtained as cubic Alabandite phase.

Pre-grinding includes coarse grinding and fine grinding, and both coarse and fine grinding are ground with water sandpaper.

The mesh number of coarse grinding is 150#, and the mesh number of fine grinding is 800#.

The polishing includes first polishing and second polishing in turn. The first polishing includes: three times of polishing with diamonds of different particle sizes as polishing agents and velvet as polishing cloths, wherein the particle size of the diamonds in the first polishing is 7 μm , The particle size of the diamond polished for the second time is 3.5 μm, and the particle size of the diamond polished for the third time is 0.5 μm;

The second polishing includes: polishing with silica sol as a polishing agent and porous neoprene as a polishing cloth, wherein the silica sol is obtained by mixing a SiO ₂ suspension with a particle size of 0.02 μm and deionized water at a ratio of 1:1 The mass ratio is mixed.

The rotational speed of the first polishing was 1500 rpm, and the time of the first polishing was 10 min.

The rotation speed of the second polishing was 150 rpm, and the time of the second polishing was 10 min.

Example 2

Comparing Embodiment 2 and Embodiment 1, the difference between Embodiment 2 and Embodiment 1 is:

S3. Scan the treated sample containing inclusions with an electron microscope to obtain an image of inclusions as shown in Figure 8, and then select position 1 for energy spectrum component analysis and Kikuchi pattern collection, respectively, as shown in Figure 9. The chemical composition of the inclusions and the tested Kikuchi pattern of the first inclusion as shown in Figure 10 show that the inclusions contain O, Al, Mg, and Fe elements;

S4. According to the chemical composition, standard chemical phases AlAl _1.67 O ₄ and MgAl ₂ O ₄ are obtained;

S51. Respectively obtain the number of kikuchi bands of the kikuchi pattern to be tested and the detection angle between the kikuchi bands to be tested;

S52. Respectively obtain the number of standard Kikuchi bands of the standard chemical phase and the standard angle between the standard Kikuchi bands;

S53. According to the number of Kikuchi bands to be tested and the number of standard Kikuchi bands, obtain the same number of Kikuchi bands between the Kikuchi pattern to be tested and the standard chemical phase;

S54. According to the detection angle and the standard angle, obtain the deviation of the detection angle between each Kikuchi band to be tested and the standard angle between the corresponding standard Kikuchi band, and then take the average value to obtain the Kikuchi pattern to be tested and the standard chemical substance mean angular deviation between phases;

S55. Obtain the matching degree between the chemical composition phase and the Kikuchi pattern to be tested according to the same number of Kikuchi bands and the average angular deviation, wherein the standard chemical phase AlAl _1.67 O ₄ phase and MgAl ₂ O ₄ phase have the same Kikuchi The number of bands is 12, and the average angular deviation is 0.43, so the two matching degrees are consistent, and it is highly likely that position 1 is the MgAl2O4 phase based on the chemical composition information;

Repeat the above steps, perform energy spectrum component analysis and Kikuchi pattern collection for the selected inclusion position 2, and obtain the chemical composition of the inclusion as shown in Figure 11 and the test Kikuchi pattern of the inclusion as shown in Figure 12, respectively, It can be seen that the inclusions contain O, Al, S, Ca, Mn, Fe elements; then according to the chemical composition, standard chemical phases CaMnS ₂ phase, Alabandite phase, Oldhamite phase, Al _21.33 S ₃₂ , (Al ₂ S ₃ ) _10.66 phase are obtained and (H ₃ O) (Al(SO ₄ ) ₂ ) phase, while the number of the same Kikuchi bands of the above standard chemical phase is 12, and the average angular deviation is 0.39;

S61. According to the matching degree and the shape of the inclusion in Figure 8, it is judged that the inclusion is not a single inclusion, and the surface distribution of the inclusion is analyzed. As shown in Figure 13, the surface distribution information of the components is obtained: O, Al and Mg elements It is distributed in the center of the inclusion, that is, at position 1, while the elements of S, Mn and Ca are distributed in the outer ring of the inclusion, that is, at position 2. Then, according to the surface distribution information of the composition and the standard chemical phase, the position 1 of the inclusion is determined. The phase type is cubic MgAl ₂ O ₄ phase, the phase type at position 2 is cubic crystal CaMnS ₂ phase, and its unit cell

One or more technical solutions in the embodiments of the present application also have at least the following technical effects or advantages:

(1) The method provided by the embodiment of the present application simplifies the sample preparation process by pre-grinding and polishing the steel sample to be tested, and then scans with an electron microscope, performs energy spectrum component analysis and Kikuchi pattern collection according to the electron microscope image, so that the energy spectrum The chemical composition obtained by the composition analysis can deduce the standard chemical composition phase, and then through the matching degree between the Kikuchi pattern to be tested and the chemical composition phase, the phase type of the inclusions can be accurately obtained, simplifying the identification process, and then realizing Simple and convenient identification of inclusions.

(2) The method provided in the embodiment of the present application can effectively remove the surface stress of the conventional metallographic polishing sample matrix and the internal inclusions by using the silica sol slow polishing sample preparation technology, and obtain a flat inclusion analysis surface, realizing the inclusion of inclusions. A clear display of the pattern of the Kikuchi belt.

(3) The method provided in the embodiment of the present application is the first to use the chemical composition information and composition surface distribution information to scientifically screen multiple phases with the same degree of matching, so as to obtain accurate inclusion phase identification results.

(4) Compared with the complex sample preparation process of X-ray diffraction (XRD) analysis and transmission electron microscope selected area electron diffraction (SAD) analysis, the method provided in the embodiment of the present application is simple in sample preparation and easier to operate, and only one sample preparation is required. Phase identification of all the inclusions of interest in the sample, rather than limited to one or two inclusions, has high analysis efficiency, simple data processing, and accurate and reliable results.

Explanation of drawings:

3 is a morphological diagram of inclusions in the steel sample to be tested provided in Example 1 of the present application;

FIG. 4 is an analysis diagram of the energy spectrum composition of the inclusions in the steel sample to be tested provided in Example 1 of the present application;

5 is an electron backscatter diffraction Kikuchi pattern diagram of inclusions in the steel sample to be tested provided in Example 1 of the application;

6 is a matching diagram of the Kikuchi pattern of the Alabandite phase and inclusions provided in Example 1 of the present application;

7 is a matching diagram of the Kikuchi pattern of MnS phase and inclusions provided in Example 1 of the present application;

It can be seen from Figures 1 to 7 that the inclusions in Example 1 are determined to be the Alabandite phase of the cubic crystal system

8 is a morphological diagram of inclusions in the steel sample to be tested provided in Example 2 of the present application;

Fig. 9 is the energy spectrum composition analysis diagram of the inclusion position 1 in the steel sample to be tested provided in Example 2 of the present application;

Fig. 10 is the electron backscatter diffraction Kikuchi pattern diagram of inclusion position 1 in the steel sample to be tested provided in Example 2 of the application;

11 is an analysis diagram of the energy spectrum composition of the inclusion position 2 in the steel sample to be tested provided in Example 2 of the application;

Fig. 12 is the electron backscatter diffraction Kikuchi pattern diagram of the inclusion position 2 in the steel sample to be tested provided in Example 2 of the application;

Figure 13 is a composition plane distribution diagram of inclusions in the steel sample to be tested provided in Example 2 of the application;

It can be seen from FIGS. 8-13 that the inclusions in Example 2 are determined to include two phases of cubic MgAl ₂ O ₄ and CaMnS ₂ .

It should be noted that, in this document, relational terms such as "first" and "second" etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply these Any such actual relationship or sequence exists between entities or operations. Moreover, the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion such that a process, method, article or device comprising a list of elements includes not only those elements, but also includes not explicitly listed or other elements inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

The above descriptions are only specific embodiments of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims (10)

1. A method for identifying a non-metallic inclusion phase, said method comprising:

obtaining a steel sample to be tested;

pre-cleaning and pre-grinding the steel sample to be detected, and then polishing to obtain a treatment sample containing impurities;

collecting the impurities in the treated sample by an electron microscope image, and then carrying out energy spectrum component analysis and chrysanthemum pool pattern collection to respectively obtain the chemical composition of the impurities and the chrysanthemum pool pattern to be detected;

obtaining a standard chemical phase according to the chemical composition;

obtaining the matching degree between the chemical composition phase and the chrysanthemum pool pattern to be detected according to the standard chemical phase and the chrysanthemum pool pattern to be detected;

and obtaining the phase type of the inclusions according to the matching degree.

2. The method according to claim 1, wherein the obtaining of the matching degree between the chemical composition phase and the flower pattern of the chrysanthemum pool to be detected according to the standard chemical phase and the flower pattern of the chrysanthemum pool to be detected specifically comprises:

respectively obtaining the number of the chrysanthemum pool zones of the chrysanthemum pool pattern to be detected and the detection angle between the chrysanthemum pool zones to be detected;

respectively obtaining the number of standard chrysanthemum pool zones of the standard chemical phase and a standard angle between the standard chrysanthemum pool zones;

obtaining the number of the chrysanthemum pool zones with the same chrysanthemum pool pattern to be detected and standard chemical phases according to the number of the chrysanthemum pool zones to be detected and the number of the standard chrysanthemum pool zones;

respectively obtaining the deviation of the detection angle between each pair of chrysanthemum pool zones to be detected and the standard angle between the corresponding standard chrysanthemum pool zones according to the detection angle and the standard angle, and then averaging to obtain the average angle deviation between the chrysanthemum pool patterns to be detected and the standard chemical phase;

and obtaining the matching degree between the chemical composition phase and the chrysanthemum pool patterns to be detected according to the same chrysanthemum pool zone number and the average angle deviation.

3. The method according to claim 2, wherein the determination principle of the matching degree is as follows: when the number of the same chrysanthemum pool strips is larger and the average angle deviation is smaller, the matching degree is higher.

4. The method according to claim 1, wherein the obtaining of the phase type of the inclusion according to the matching degree specifically comprises:

judging whether the inclusion is a single inclusion or not according to the matching degree;

if so, screening the chrysanthemum pool pattern to be detected according to the standard chemical phase to obtain the phase type of the inclusion;

and if not, performing component surface distribution analysis on the processed sample to obtain surface distribution information of the components, and then obtaining the phase type of the inclusions according to the surface distribution information of the components and the standard chemical phase.

5. The method of claim 1, wherein the pre-grinding comprises coarse and fine grinding, both of which are ground with water sandpaper.

6. The method of claim 1, wherein the coarse grinding has a mesh size of 100# to 200# and the fine grinding has a mesh size of 750# to 850 #.

7. The method of claim 1, wherein the polishing comprises a first polishing and a second polishing in sequence, the first polishing comprising: polishing for many times by taking diamonds with different grain diameters as a polishing agent and taking velvet as polishing cloth;

the second polishing includes: polishing is carried out by taking silica sol as a polishing agent and porous chloroprene rubber as polishing cloth.

8. The method according to claim 7, wherein the rotation speed of the first polishing is 900rpm to 1500rpm, and the time of the first polishing is 5min to 15 min.

9. The method of claim 7, wherein the rotation speed of the second polishing is 100rpm to 150rpm, and the time of the second polishing is 10min to 15 min.

10. The method of claim 7, wherein the diamond has a particle size of 0.5 to 7 μm.

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