Sample preparation method for intelligent analysis of steel and iron materials

Abstract

The invention relates to a sample preparation method for intelligent analysis of a steel material, and belongs to the technical field of steel detection. The method comprises the steps that a to-be-tested sample is obtained, the to-be-tested sample is provided with a to-be-tested face, and the flatness of the to-be-tested face meets the condition that the difference value between the highest point and the lowest point does not exceed 0.5 mm; polishing the opposite surface of the to-be-tested surface of the to-be-tested sample; grinding the to-be-tested surface of the to-be-tested sample; cleaning a to-be-tested surface of the ground to-be-tested sample to obtain a to-be-analyzed sample; by controlling the difference value between the highest point and the lowest point of the surface to be detected not to exceed 0.5 mm, the reliability of the intelligent analysis sample is improved, so that the whole surface to be detected is matched with the focusing capability of intelligent analysis equipment, the inclusions can be better distinguished, and the analysis accuracy is improved.

Description

Technical Field

[0001] The present application relates to the technical field of steel material detection, and in particular to a sample preparation method for intelligent analysis of steel materials. Background Art

[0002] Intelligent analysis is accurate, efficient, and highly automated, and is now the focus of technological development for major steel companies. Such artificial intelligence technologies include fully automatic inclusion metallographic rating, grain size rating, fully automatic inclusion detection statistics, and intelligent analysis statistics of precipitates. However, the basis for the realization of intelligent analysis functions is the reliability of the early sample preparation, and the reliability of the current sample preparation still needs to be improved. Summary of the invention

[0003] The present application provides a sample preparation method for intelligent analysis of steel materials to improve the reliability of intelligent analysis samples.

[0004] The present application provides a sample preparation method for intelligent analysis of steel materials, the method comprising:

[0005] A sample to be tested is obtained, wherein the sample to be tested has a surface to be tested, and the flatness of the surface to be tested satisfies that: the difference between the highest point and the lowest point does not exceed 0.5 mm;

[0006] Grinding the opposite side of the surface to be tested of the sample to be tested;

[0007] Grinding the test surface of the test sample;

[0008] The test surface of the sample to be tested that has been ground is cleaned to obtain a sample to be analyzed.

[0009] As an optional implementation manner, the sample to be tested is in a prism shape, and the surface to be tested is a longitudinal section of the sample to be tested; and / or

[0010] The sample to be tested is cylindrical, and the surface to be tested is a circular cross section of the sample to be tested.

[0011] As an optional implementation, the sandpaper used for grinding is No. 200 sandpaper.

[0012] As an optional implementation, the grinding includes coarse grinding, fine grinding, rough polishing, fine polishing, rinsing and clean polishing.

[0013] As an optional embodiment, the sandpaper used for the rough grinding is 200-grinding sandpaper and 600-grinding sandpaper; and / or

[0014] The sandpaper used for the fine grinding is No. 1000 sandpaper and No. 1200 sandpaper.

[0015] As an optional implementation, the flushing liquid is alcohol, and the volume concentration of the alcohol is above 95%.

[0016] As an optional implementation, the polishing includes: polishing with a polishing disc that is not sprayed with polishing agent.

[0017] As an optional implementation, the cleaning includes drying, wiping, wiping and protecting with a cleaning tape.

[0018] As an optional implementation, the drying is performed using hot air; and / or

[0019] The wiping is performed using compressed air.

[0020] As an optional implementation, the wiping liquid includes isopropyl alcohol.

[0021] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0022] The method provided in the embodiment of the present application improves the reliability of intelligent analysis samples by controlling the difference between the highest point and the lowest point of the test surface to be no more than 0.5 mm, so that the entire test surface matches the focusing capability of the intelligent analysis equipment, thereby better distinguishing inclusions and improving the accuracy of the analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 A schematic diagram of the BSD morphology of foreign pollutants for intelligent analysis provided in an embodiment of the present application;

[0026] Figure 2 A schematic diagram of the morphology of grinding and polishing scratches provided by the intelligent analysis of an embodiment of the present application;

[0027] Figure 3 A schematic diagram of the morphology of micro-pits for intelligent analysis provided in an embodiment of the present application;

[0028] Figure 4 A flowchart of the method provided in the embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0030] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0031] The basis for the realization of intelligent analysis functions is the reliability of the preliminary sample preparation. The current sample preparation plan is: according to the research needs, the sample is processed into specifications and sizes that meet the test requirements, and the surface to be tested is determined. Before grinding, the opposite side of the surface to be tested is first polished with No. 200 sandpaper to ensure the smoothness of the bottom of the sample and improve the conductivity of the sample. Then the surface to be tested is ground in sequence from coarse to fine (200-600-1000-1200 mesh) with sandpaper, and each pass must ensure that the scratches of the previous pass are completely polished away. After grinding, the sample is mechanically polished, and the interval time between each pass of grinding and polishing should not be too long. However, the fine sandpaper particles, polishing agent particles, velvet fibers, fine dust, fine scratches, etc. brought about by the sample preparation process. These will interfere with the automatic analysis of the intelligent analysis equipment. For example, the fully automatic inclusion analysis equipment will count all detected particles that are different from the steel matrix as inclusions, and cannot distinguish whether the inclusion is originally present in the steel matrix or attached externally. Typical phenomena such as Figure 1 , Figure 2 , Figure 3 As shown (all pictures are collected in the backscattering mode of ASPEX large inclusion analyzer). Figure 1 The foreign pollutants in the water vary in size and contain irregular elements, mainly Na, Cl and other elements. Figure 2 The scratches in the sample are typical two-dimensional defects, very small, and usually Fe or Fe-O. Figure 3 The micro-pits in the sample are small in size and are usually Fe or Fe-O, with a few containing trace amounts of Mn. They are usually found in ingot samples. They may be caused by holes that originally existed inside the ingot, or they may be scars left by the rapid oxidation and oxide shedding during the later processing. This results in the detection accuracy of ASPEX for automatic identification of inclusions being only 54.43%. Therefore, it is particularly important to improve the sample preparation effect for intelligent analysis.

[0032] To this end, the present application intends to provide a sample preparation method for intelligent analysis of steel materials to improve the reliability of intelligent analysis samples.

[0033] The applicant believes that if the accuracy of automatic identification of the equipment is to be guaranteed, the cleanliness of the test surface of the sample must be guaranteed. All interference from foreign matter must be removed as much as possible to ensure the accuracy of the test results.

[0034] Figure 4 A flow chart of the method provided in the embodiment of the present application is as follows: Figure 4 As shown, the embodiment of the present application provides a sample preparation method for intelligent analysis of steel materials, the method comprising:

[0035] S1. Obtain a sample to be tested, wherein the sample to be tested has a surface to be tested, and the flatness of the surface to be tested satisfies: the difference between the highest point and the lowest point does not exceed 0.5 mm;

[0036] Since most intelligent analysis software is used in conjunction with magnifying devices such as electron microscopes or optical microscopes, it is necessary to use electron microscopes or optical microscopes to collect images of samples. For example, the automatic identification of inclusions is based on the stability of the brightness and contrast on the surface to be tested during the scanning process. Therefore, the parallelism of the surface to be tested must be strictly controlled during the early sample preparation process to ensure that the WD difference (working distance) between the highest and lowest points in the inspected area does not exceed 0.5mm. If the WD difference is too large and exceeds the automatic focusing capability of the equipment, the brightness contrast of the BSD component phase presented by the inclusion itself will have errors, which will ultimately result in inaccurate EDS analysis results of inclusions and unclear inclusion image acquisition.

[0037] Specifically, in order to better ensure the parallelism of the sample surface to be tested, we can start from the following two aspects: First, ensure the accuracy of sample machining; second, use professional sample fixtures as much as possible. The fixture includes a sample fixture and a fixture base for mounting the sample. The sample fixture is provided with a mounting position for the sample. The sample fixture can match the fixture base, and the fixture base can be installed in the testing equipment. The fixing bolts of the sample fixture are located at the bottom of the surface to be tested, with the clamping edge in the direction of the surface to be tested as the reference, which better ensures the parallelism of the surface to be tested. The fixture can hold multiple samples at a time, and all the sample test surfaces can be guaranteed to be at a certain degree of parallelism, so that multiple samples can be tested at one time, and no experimental operations are required during the experiment. Different bases are made according to different experimental equipment. It not only improves the test efficiency, but also ensures the accuracy of the test results.

[0038] In some embodiments, the sample to be tested is prismatic, and the surface to be tested is the longitudinal section of the sample to be tested. For example, the sample to be tested may be a coil or a billet, and the dimensions of the coil sample may satisfy: length × width × height = (30 ± 0.5 mm) × plate thickness × (14 to 15 mm); the dimensions of the billet sample may satisfy: length × width × height = (30 ± 0.5 mm) × (3 mm to 80 mm) × (14 to 15 mm).

[0039] In some embodiments, the sample to be tested is cylindrical, and the test surface is a circular cross section of the sample to be tested. The size of the cylindrical sample can meet the following requirements: (φ30±0.5mm)×(14-15mm).

[0040] It should be noted that the dimensions of the above specimens can be adjusted according to the actual fixture used.

[0041] S2. Grinding the opposite side of the surface to be tested of the test sample;

[0042] After the opposite side of the test surface of the test sample is polished, the smoothness of the bottom of the sample is ensured and the conductivity of the sample is improved.

[0043] In some embodiments, the sandpaper used for polishing is 200 grit sandpaper.

[0044] S3. Grinding the test surface of the test sample;

[0045] In some embodiments, the grinding includes coarse grinding, fine grinding, rough polishing, fine polishing, rinsing and clean polishing. Further, the sandpaper used in the coarse grinding is 200 sandpaper and 600 sandpaper; the sandpaper used in the fine grinding is 1000 sandpaper and 1200 sandpaper. The rinsing liquid is alcohol, and the volume concentration of the alcohol is above 95%.

[0046] In some embodiments, polishing includes: polishing with a polishing disc that is not sprayed with a polishing agent. Polishing can clean the surface of the sample to be tested again, and at the same time, it can remove water stains and avoid oxidation and pitting.

[0047] Specifically, in this embodiment, the surface to be tested is ground in sequence with sandpaper from coarse to fine (No. 200-600-1000-1200), and each pass must ensure that the scratches of the previous pass are thoroughly polished off. After the fine grinding is completed, the sample is mechanically polished, and the interval time between each pass of grinding and polishing should not be too long. This procedure is the same as the preparation of metallographic samples in production, and is called conventional metallographic grinding and polishing. After the grinding and polishing is completed, the sample should be vigorously rinsed with industrial alcohol with a concentration of more than 95% to rinse off the dirt scraped and stuck to the periphery of the sample during the grinding and polishing process, but the rinsing time should not be too long to prevent the surface to be tested from being oxidized. After rinsing is completed, quickly polish dry the water on a clean polishing disc that has not been sprayed with any polishing agent. It should be noted that during the grinding and polishing process, the interval time between each pass should not be too long to avoid oxidation.

[0048] S4. Cleaning the test surface of the sample to be tested after the grinding to obtain a sample to be analyzed.

[0049] In some embodiments, the cleaning includes blow drying, blowing, wiping, and cleaning tape protection.

[0050] Furthermore, the drying is performed by hot air, and specifically by an electric hair dryer, so as to keep the sample clean and dry as a whole, so as to avoid excessive moisture during vacuuming, which may affect the equipment. The drying process may be performed by first drying the surface to be tested at a 45° angle, and then drying the sample as a whole.

[0051] Furthermore, the wiping is performed using compressed air. Specifically, the sample can be wiping with compressed air, mainly to blow away the sticky velvet and other dirt around the surface to be tested, and to avoid bringing the dirt on the edge to the surface to be tested when wiping with isopropyl alcohol in the next step.

[0052] Furthermore, the wiping liquid includes isopropyl alcohol. Specifically, a small amount of isopropyl alcohol can be dipped into a dust-free cloth and wiped quickly in one direction. The number of wiping times is controlled within 3 times. Wiping multiple times or wiping too slowly will cause an oxide film on the surface that cannot be removed.

[0053] The cleaning tape protection can prevent the surface to be tested from being damaged or contaminated by human factors during the process of installing the sample and adjusting the height of the sample stage. The cleaning tape can also be used for secondary cleaning of the surface to be tested.

[0054] It should be noted that during the test, after removing the cleaning tape, you can blow it again. Specifically, after the sample is placed and adjusted, tear off the cleaning tape, and before closing the sample compartment door, use compressed air to blow the sample and all parts of the sample compartment for the last time, trying to keep the sample compartment clean and tidy to avoid external contamination affecting the test results. This ensures the overall cleanliness of the sample to a greater extent.

[0055] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0056] Example

[0057] A sample preparation method for intelligent analysis of steel materials, the method comprising:

[0058] S1. Obtain a sample to be tested, wherein the sample to be tested has a surface to be tested, and the flatness of the surface to be tested satisfies: the difference between the highest point and the lowest point does not exceed 0.5 mm;

[0059] S2. Grind the opposite side of the test surface of the test sample; the sandpaper used for grinding is No. 200 sandpaper

[0060] S3. Grind the test surface of the test sample; grinding includes rough grinding, fine grinding, rough polishing, fine polishing, rinsing and clean polishing; the sandpaper used for rough grinding is 200 sandpaper and 600 sandpaper; the sandpaper used for fine grinding is 1000 sandpaper and 1200 sandpaper; the rinsing liquid is alcohol, and the volume concentration of the alcohol is more than 95%. Clean polishing includes: polishing with a polishing disc that is not sprayed with polishing agent.

[0061] S4. Clean the test surface of the sample to be tested after the grinding to obtain the sample to be analyzed. Cleaning includes drying, wiping, wiping and cleaning tape protection; the drying is performed by hot air; the wiping is performed by compressed air; the wiping liquid includes isopropyl alcohol.

[0062] Comparative Example

[0063] A sample preparation method for intelligent analysis of steel materials, the method comprising:

[0064] After obtaining the sample to be tested, first grind the opposite side of the surface to be tested with 200-grit sandpaper to ensure the smoothness of the bottom of the sample to be tested and improve the conductivity of the sample to be tested. Then grind the surface to be tested with sandpaper from coarse to fine (200-600-1000-1200 mesh) in sequence, and ensure that the scratches of the previous pass are completely polished off in each pass to obtain the sample to be analyzed.

[0065] A batch of steel was analyzed for inclusions using the methods provided in the examples and comparative examples. The accuracy of the analysis is shown in the following table:

[0066] Accuracy Example 97.05％ Comparative Example 54.43％

[0067] It can be seen from the above table that the sample to be analyzed prepared by the method provided in the embodiment of the present application can effectively improve the accuracy of intelligent analysis.

[0068] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0069] In the present application, in the absence of any contrary description, the directional words used, such as "upper" and "lower", are specifically the directions of the drawings in the accompanying drawings. In addition, in the description of the present specification, the terms "including", "comprising", etc. refer to "including but not limited to". In this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of the associated objects, indicating that there may be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A, B can be singular or plural. In this article, "at least one" refers to one or more, and "plural" refers to two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, "at least one of a, b or c", or "at least one of a, b and c", can both mean: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b and c can be single or multiple.

[0070] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A sample preparation method for intelligent analysis of steel materials, characterized in that: The method comprises: A sample to be tested is obtained, wherein the sample to be tested has a surface to be tested, and the flatness of the surface to be tested satisfies that: the difference between the highest point and the lowest point does not exceed 0.5 mm; Grinding the opposite side of the surface to be tested of the sample to be tested; Grinding the test surface of the test sample; The test surface of the sample to be tested that has been ground is cleaned to obtain a sample to be analyzed.

2. The sample preparation method for intelligent analysis of steel materials according to claim 1, characterized in that: The sample to be tested is in a prism shape, and the surface to be tested is a longitudinal section of the sample to be tested; and / or The sample to be tested is cylindrical, and the surface to be tested is a circular cross section of the sample to be tested.

3. The sample preparation method for intelligent analysis of steel materials according to claim 1, characterized in that: The sandpaper used for the polishing is No. 200 sandpaper.

4. The sample preparation method for intelligent analysis of steel materials according to claim 1, characterized in that: The grinding includes coarse grinding, fine grinding, rough polishing, fine polishing, flushing and clean polishing.

5. The sample preparation method for intelligent analysis of steel materials according to claim 4, characterized in that: The sandpaper used for the rough grinding is 200-grit sandpaper and 600-grit sandpaper; and / or The sandpaper used for the fine grinding is No. 1000 sandpaper and No. 1200 sandpaper.

6. The sample preparation method for intelligent analysis of steel materials according to claim 4, characterized in that: The flushing liquid is alcohol, and the volume concentration of the alcohol is above 95%.

7. The sample preparation method for intelligent analysis of steel materials according to claim 4, characterized in that: The polishing comprises: polishing with a polishing disc which is not sprayed with polishing agent.

8. The sample preparation method for intelligent analysis of steel materials according to claim 1, characterized in that: The cleaning includes drying, blowing, wiping and cleaning tape protection.

9. The sample preparation method for intelligent analysis of steel materials according to claim 8, characterized in that: The drying is performed by hot air; and / or The wiping is performed using compressed air.

10. The sample preparation method for intelligent analysis of steel materials according to claim 8, characterized in that: The wiping liquid includes isopropyl alcohol.

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