Method for continuously detecting non-metallic inclusions in steel samples with different heights by utilizing OTS

Abstract

The invention belongs to the technical field of analysis and detection of steel and iron materials, and particularly relates to a method for continuously detecting non-metallic inclusions in steel samples with different heights by utilizing OTS. Comprising the following steps: sequentially preparing a compensating plate, screening a deviation sample group, performing height compensation on a metallographic sample in the deviation sample group by using the compensating plate, and performing sample detection on the compensated deviation sample group. According to the invention, the metallographic sample with large height deviation can be continuously detected, on one hand, continuous work of the electron microscope can be realized without guarding and manpower is saved, on the other hand, an emitter of the electron microscope can be saved, continuous work of the emitter after detection of one sample is avoided, the cost is saved, and the detection efficiency is improved. Therefore, the working efficiency of detecting the non-metallic inclusions by using the OTS full-automatic analysis system for the non-metallic inclusions in the steel is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of steel material analysis and detection, and in particular relates to a method for continuously detecting non-metallic inclusions in steel samples of different heights by utilizing OTS. Background Art

[0002] The OTS fully automatic non-metallic inclusion analysis system in steel is a comprehensive analysis system that integrates a scanning electron microscope, a large-area high-speed energy spectrum detector, automatic inclusion analysis software, and sample cleanliness evaluation and recommendations.

[0003] OTS fully automatic non-metallic inclusion analysis system in steel has many advantages:

[0004] (1) Inclusion analysis can be performed quantitatively.

[0005] (2) The analysis speed is fast and the information such as photos, location, size and morphology of all inclusion particles are automatically stored.

[0006] (3) Inclusions of a certain size or composition can be selectively detected and analyzed.

[0007] (4) Automatic report generation function. It can not only generate statistical reports based on the size and chemical composition of inclusions, but also reflect the composition distribution of all inclusions on a custom ternary distribution diagram, allowing users to see the composition distribution of inclusions at a glance.

[0008] Although the OTS fully automatic non-metallic inclusion analysis system in steel has many advantages, it also has certain disadvantages. Among them, we need wire cutting machine cutting, grinding wheel machine grinding, metallographic grinding machine grinding, polishing agent polishing and other processes in the sample preparation process. This process requires manual participation, so it is impossible to make the sample completely flat. At this time, if in order to improve the detection efficiency, it is impossible to use the OTS fully automatic non-metallic inclusion analysis system to continuously detect samples of different heights. This is because the clarity and resolution of the images of samples of different heights under the electron microscope are different, which makes the detection of non-metallic inclusions have large deviations. The height difference of the sample for continuous detection must be less than 0.1mm, so that the focus can be clear, otherwise synchronous detection cannot be achieved. Summary of the invention

[0009] The object of the present invention is to provide a method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS, so as to solve the problems existing in the prior art.

[0010] The technical solution adopted by the present invention to solve its technical problem is:

[0011] A method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS comprises sequentially preparing compensation sheets, screening deviation sample groups, performing height compensation on metallographic samples in the deviation sample groups using the compensation sheets, and performing sample detection on the compensated deviation sample groups.

[0012] Furthermore, the method for preparing the compensation sheet is to process or purchase a number of stainless steel sheets with different thicknesses, and cut the stainless steel sheets into compensation sheets as required for later use.

[0013] Furthermore, the thickness of the stainless steel sheet increases gradually from 0.1 mm in thickness increments of 0.1 mm.

[0014] Furthermore, the method for screening the deviation sample group is to subject the sample to be tested to wire cutting, grinding with a grinder, grinding with a metallographic grinder, and polishing with a polishing agent, and finally obtain a number of metallographic samples, measure the height of each metallographic sample with a vernier caliper, and divide the metallographic samples into a number of normal sample groups and deviation sample groups according to the standard height difference and the maximum number of sample injections.

[0015] Furthermore, the maximum number of injections is the maximum number of metallographic samples that the electron microscope sample stage of the OTS system can carry for each inspection;

[0016] The standard height difference is the height difference between metallographic samples when multiple metallographic samples are tested at the same time. The standard height difference is 0.1mm.

[0017] A normal sample group is one in which the number of metallographic samples in the group is the maximum number of samples, and the height difference between each metallographic sample in the group is less than or equal to the standard height difference;

[0018] The deviation sample group is that the number of metallographic samples in the group is less than or equal to the maximum number of samples, and the height difference between at least two metallographic samples in the group is greater than the standard height difference.

[0019] Furthermore, the method of height compensation is to take the highest metallographic sample in each deviation sample group as the standard, calculate the height difference between each remaining metallographic sample and the highest metallographic sample, select the corresponding compensation sheet according to the calculated height difference, and stick the compensation sheet on the corresponding metallographic sample with conductive adhesive, so that the height difference between each metallographic sample in the same deviation sample group is less than or equal to the standard height difference.

[0020] Furthermore, the method for sample detection is to take a group of deviation samples, glue all the metallographic samples therein to the electron microscope sample stage of the OTS system with conductive glue, and glue one end of the compensation sheet of the deviation sample with a compensation sheet to the electron microscope sample stage of the OTS system with conductive glue, evacuate the vacuum, turn on the high voltage, adjust the focus and brightness contrast of the electron microscope, adjust its grayscale so that inclusions and matrix can be well distinguished, turn on the OTS software, and perform synchronous detection. The normal sample group is detected according to the normal detection process.

[0021] The present invention has the following beneficial effects:

[0022] The present invention compensates the height of the metallographic sample by a compensation sheet, and sticks the compensation sheet on the metallographic sample with a conductive adhesive, so that the metallographic sample with a large height deviation can also meet the requirement of a height difference of less than 0.1 mm, so that the resolution and clarity can be consistent at the same working distance, so that the non-metallic inclusions of multiple metallographic samples with large height deviations can be detected synchronously. On the one hand, the electron microscope can be operated continuously without supervision, saving manpower; on the other hand, the transmitter of the electron microscope can be saved, avoiding the transmitter from working continuously after detecting a sample, saving costs; thereby improving the work efficiency of detecting non-metallic inclusions using the OTS fully automatic non-metallic inclusion analysis system in steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a physical picture of the metallographic sample in the deviation sample group screened out by the present invention.

[0024] Figure 2 This is a physical picture of the compensation sheet of the present invention.

[0025] Figure 3 It is a physical picture of the metallographic sample with the compensation sheet pasted on it according to the present invention.

[0026] Figure 4 This is a real picture of a metallographic sample with a compensation sheet attached thereto and attached to a sample stage of an electron microscope of an OTS system.

[0027] Figure 5 It is a software interface diagram when the present invention detects the metallographic samples in the deviation sample group through the OTS system. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] like Figure 1-5 As shown, a method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS comprises sequentially performing:

[0030] (1) Preparation of compensation sheets: Process or purchase several stainless steel sheets of different thicknesses. The thickness of the stainless steel sheets starts from 0.1mm and increases with a thickness difference of 0.1mm. That is, prepare stainless steel sheets of 0.1mm, 0.2mm, 0.3mm, ..., Nmm, where N is the thickness of the thickest stainless steel sheet. The value of N is determined according to the actual situation of the metallographic samples processed at ordinary times, so it is not limited. For example, when processing metallographic samples at ordinary times, the maximum height difference of the metallographic samples (the height difference between the lowest and highest metallographic samples) is 4mm. Occasionally, the maximum height difference is greater than 4mm. In this case, when preparing compensation sheets, we can prepare stainless steel sheets with a thickness of 4mm or less and cut them into compensation sheets.

[0031] When the maximum height difference is greater than 4mm occasionally, it can be processed at that time or the metallographic sample can be tested separately. The specific measures can be selected according to the actual situation. If the processing is convenient, then choose to process at that time; if the processing is inconvenient or time-consuming, then the metallographic sample can be tested separately to save time. In other words, the compensation sheets of commonly used thickness specifications are prepared for standby, and other specifications are processed at that time or tested separately, which can improve the efficiency of the test.

[0032] Since each steel mill has different size requirements for metallographic samples, the sizes of metallographic samples and compensation sheets are not limited. The size requirement of the metallographic sample in this embodiment is based on a cube shape of 20mm×20mm×20mm, so the compensation sheet is cut into a square with a side length of 2mm.

[0033] (2) Screening deviation sample groups: The samples to be tested are subjected to wire cutting, grinding with a grinding machine, grinding with a metallographic grinding machine, and polishing with a polishing agent to finally obtain a number of metallographic samples. The height of each metallographic sample is measured with a vernier caliper, and the metallographic samples are divided into a number of normal sample groups and deviation sample groups according to the standard height difference and the maximum number of sample injections.

[0034] The maximum number of injections is the maximum number of metallographic samples that the electron microscope sample stage of the OTS system can carry for each test; the standard height difference is the difference in height between metallographic samples when multiple metallographic samples are tested at the same time, and the standard height difference is 0.1mm; the normal sample group is that the number of metallographic samples in the group is the maximum number of injections, and the height difference between each metallographic sample in the group is less than or equal to the standard height difference; the deviation sample group is that the number of metallographic samples in the group is less than or equal to the maximum number of injections, and the height difference between at least two metallographic samples in the group is greater than the standard height difference.

[0035] Under the size requirements of the metallographic samples in this embodiment, the electron microscope sample stage of the OTS system can place up to 4 metallographic samples for each test. Since the surface of the metallographic samples needs to meet the test requirements when processing the samples to be tested, it is impossible to ensure that the height of all metallographic samples is 20mm. There are always some metallographic samples with too large height deviations, so they need to be screened.

[0036] like Figure 1 As shown, the height deviation of a deviation sample group screened out is relatively large. The metallographic samples are arranged from low to high and numbered 1#, 2#, 3#, and 4#, with heights of 17.6mm, 18.3mm, 19.4mm, and 20.5mm, respectively.

[0037] (3) Height compensation: Taking the highest metallographic sample in each deviation sample group as the standard, calculate the height difference between each remaining metallographic sample and the highest metallographic sample, select the corresponding compensation sheet according to the calculated height difference, and stick the compensation sheet on the corresponding metallographic sample with conductive adhesive, so that the height difference between each metallographic sample in the same deviation sample group is less than or equal to the standard height difference.

[0038] The maximum height of the 4# metallographic sample in step (2) is 20.5 mm, and the height differences between 1#, 2#, 3# and 4# are 2.9 mm, 2.2 mm, and 1.1 mm, respectively.

[0039] like Figure 2-3 As shown, three compensation sheets with thicknesses of 2.9 mm, 2.2 mm, and 1.1 mm are found from the compensation sheets, and the three compensation sheets with thicknesses of 2.9 mm, 2.2 mm, and 1.1 mm are respectively pasted on the bottom of 1#, 2#, and 3# metallographic samples by conductive adhesive, so that the height differences between 1#, 2#, 3# metallographic samples and 4# metallographic sample are all smaller than the standard height difference.

[0040] (4) Sample testing: Figure 4-5 As shown, each metallographic sample in a deviation sample group is glued to the electron microscope sample stage of the OTS system with conductive glue. When the metallographic sample with a compensation sheet is glued, one end of the compensation sheet is glued to the electron microscope sample stage of the OTS system with conductive glue. The vacuum is drawn, the high voltage is turned on, the focus and brightness contrast of the electron microscope are adjusted, and its grayscale is adjusted so that the inclusions and the matrix can be well distinguished. The OTS software is turned on and the four samples are tested synchronously.

[0041] The above-described embodiments are merely descriptions of preferred implementations of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by ordinary persons in the art to the technical solution of the present invention should all fall within the scope of protection of the present invention.

[0042] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS, characterized in that: The method comprises the following steps: preparing compensation sheets, screening deviation sample groups, performing height compensation on metallographic samples in the deviation sample groups by using the compensation sheets, and performing sample testing on the compensated deviation sample groups.

2. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 1, characterized in that: The method for preparing the compensation sheet is to process or purchase a number of stainless steel sheets with different thicknesses, and cut the stainless steel sheets into compensation sheets as required for later use.

3. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 2, characterized in that: The thickness of the stainless steel sheet increases gradually from 0.1 mm in thickness increments of 0.1 mm.

4. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 1, characterized in that: The method for screening the deviation sample group is to subject the sample to be tested to wire cutting, grinding with a grinder, grinding with a metallographic grinding machine, and polishing with a polishing agent to finally obtain a number of metallographic samples, measure the height of each metallographic sample with a vernier caliper, and divide the metallographic samples into a number of normal sample groups and deviation sample groups according to the standard height difference and the maximum number of sample injections.

5. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 4, characterized in that: The maximum number of injections is the maximum number of metallographic samples that the electron microscope sample stage of the OTS system can carry for each test; The standard height difference is the height difference between metallographic samples when multiple metallographic samples are tested at the same time. The standard height difference is 0.1mm. A normal sample group is one in which the number of metallographic samples in the group is the maximum number of samples, and the height difference between each metallographic sample in the group is less than or equal to the standard height difference; The deviation sample group is that the number of metallographic samples in the group is less than or equal to the maximum number of samples, and the height difference between at least two metallographic samples in the group is greater than the standard height difference.

6. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 5, characterized in that: The height compensation method is to take the highest metallographic sample in each deviation sample group as the standard, calculate the height difference between each remaining metallographic sample and the highest metallographic sample, select the corresponding compensation sheet according to the calculated height difference, and stick the compensation sheet on the corresponding metallographic sample through conductive adhesive, so that the height difference between each metallographic sample in the same deviation sample group is less than or equal to the standard height difference.

7. The method for continuously detecting non-metallic inclusions in steel samples of different heights using OTS according to claim 6, characterized in that: The sample detection method is as follows: taking a group of deviation samples, gluing all metallographic samples therein on the electron microscope sample stage of the OTS system with conductive glue, gluing one end of the compensation sheet of the deviation sample with a compensation sheet on the electron microscope sample stage of the OTS system with conductive glue, evacuating, turning on high voltage, adjusting the focus and brightness contrast of the electron microscope, adjusting its grayscale so that inclusions and matrix can be well distinguished, turning on the OTS software, and performing synchronous detection, and detecting the normal sample group according to the normal detection process.

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