CN110174402B - Method for distinguishing red oxide skin and red corrosion product of hot rolled steel - Google Patents
Method for distinguishing red oxide skin and red corrosion product of hot rolled steel Download PDFInfo
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- CN110174402B CN110174402B CN201910400868.3A CN201910400868A CN110174402B CN 110174402 B CN110174402 B CN 110174402B CN 201910400868 A CN201910400868 A CN 201910400868A CN 110174402 B CN110174402 B CN 110174402B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
- G01N2001/2873—Cutting or cleaving
Abstract
The invention discloses a method for distinguishing a red oxide skin and a red corrosion product of hot rolled steel, which comprises the following steps: preparing a sample: cutting the hot rolled steel with red surface into single samples; searching a target area by adopting parallel light: observing by using a microscope with a polarizer and an analyzer, extracting the polarizer during observation, stopping using the polarizer and the analyzer, switching the microscope to a bright field imaging mode, observing the surface or the cross section of a sample, adjusting the imaging mode of the microscope to be colored, and adjusting the magnification to find a target area; observing the target area by adopting polarized light: pushing a polarizer to the bottom of a microscope, starting the polarizer and an analyzer, switching the microscope to a polarized light imaging mode, adjusting the polarizer and the analyzer of the microscope to be in an orthogonal state, and shooting a target area by adopting orthogonal polarized light to obtain a polarized light picture; and (6) classifying the result. The method can quickly distinguish the types of the surface red substances and has short test time.
Description
Technical Field
The invention relates to a steel analysis and detection method, in particular to a method for distinguishing red oxide skin and red corrosion products of hot rolled steel.
Background
The hot rolled steel is corroded during shipping or storage, wherein the surface scale has a large influence on the corrosion resistance of a matrix, and the microstructure, the chemical composition and the like of the scale are closely related. Research shows that the oxide scale phases are FeO and Fe from inside to outside in sequence3O4And Fe2O3The color states are blue, black and red. If the oxide scale is red Fe formed at high temperature2O3The reason for the red color is not easily distinguished by the oxide scale, while the hot rolled steel is in contact with the process water, or yellow or red corrosion products are formed during the humid air standing. Hot rolled steelAt the time of shipment, there are generally stringent surface quality requirements and it is generally undesirable to see a red-emitting scale. Furthermore, studies have shown that hot rolled steel scales, which are very susceptible to corrosion products on their surface, have poor corrosion resistance in storage and transportation environments. In order to improve the surface quality of the hot rolled steel and the corrosion resistance of the hot rolled steel with oxide skin in storage and transportation environments, the structural type of the oxide skin needs to be controlled. It is therefore of interest to distinguish whether the red-coloured material of the hot-rolled steel is scale or corrosion products in order to control the structure of the scale. At present, an X-ray diffraction method is mostly adopted to test and distinguish whether a red substance is an oxide skin or a corrosion product, but the original sample is damaged during sample preparation, and the in-situ analysis cannot be carried out. And the sample preparation is complicated, and the test and analysis process is long.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide a method for distinguishing red oxide skin and red corrosion products of hot rolled steel, which can perform in-situ analysis, has short testing time and is simple and convenient to operate.
The technical scheme is as follows: the invention provides a method for distinguishing red oxide skin and red corrosion products of hot rolled steel, which comprises the following steps:
(1) preparing a sample: cutting hot rolled steel with red surface into single samples, and keeping the surfaces of the samples free of damage;
(2) searching a target area by adopting parallel light: observing a sample by using a microscope with a polarizer and an analyzer, extracting the polarizer during observation, stopping using the polarizer and the analyzer, switching the microscope to a bright field imaging mode, observing the surface or the cross section of the sample by adopting parallel light, adjusting the imaging mode of the microscope to be colored, and adjusting the magnification factor according to needs to find a target area;
(3) observing the target area by adopting polarized light: pushing a polarizer to the bottom of a microscope, starting the polarizer and an analyzer, switching the microscope to a polarized light imaging mode, adjusting the polarizer and the analyzer of the microscope to be in an orthogonal state, and shooting a target area by adopting orthogonal polarized light to obtain a polarized light picture;
(4) and (4) classification: and distinguishing oxide skin and corrosion products according to different colors of the pictures.
Further, the hot rolled steel in the step (1) is cut by flame cutting or mechanical cutting. And (2) cutting the hot rolled steel in the step (1) into samples with the length of less than 100mm, the width of less than 100mm and the thickness of less than 30 mm. The magnification of the step (2) is 100 times or 200 times. The microscope is a metallographic microscope.
The method of the present invention uses a reflection type polarization microscope because the polarization microscope is very practical for identifying whether a certain substance is mono-refractive (isotropic) or birefringent (anisotropic), and a steel substrate cannot transmit light, so that the reflection type polarization microscope is used instead of the transmission type polarization microscope. The scale produced by the hot rolled steel at high temperature is generally amorphous, isotropic and extinction under cross-polarization microscope, while the outer layer of corrosion products is generally crystalline FeOOH and bright yellow or red under cross-polarization. Although the formation of red scale at high temperatures is visually indistinguishable from corrosion products, it is distinguishable under a polarizing microscope. And the sample is observed by adopting parallel light, so that a target area can be conveniently and quickly found. The oxide scale can see the best visual field effect under the magnification of 100-200 times, so the magnification is generally selected from 100-200 times.
Has the advantages that: the method can quickly distinguish the type of red substances on the surface of the hot rolled steel, find out the reason of the problem of the surface quality in time, is valuable for improving the surface quality of the hot rolled steel, reduces the waste judgment rate of the produced product and brings direct economic benefit; the method is convenient to operate, short in testing time and approximately 3-20 minutes for completing the test of one sample.
Drawings
FIG. 1 is a surface polarization picture of X65 hot rolled steel;
FIG. 2 is a cross-sectional polarization picture of AH36 hot rolled steel.
Detailed Description
Example 1
The X65 pipeline steel plate produced by the hot rolling controlled cooling process has the thickness of 16mm and the color of the steel plate is red. The method for distinguishing the types of red substances by using the ZEISS Axio Imager M2M metallographic microscope with a polarizer and an analyzer comprises the following steps:
(1) and (5) preparing a sample. The red-surface X65 steel is mechanically cut into 30X 16mm samples, and the original surface state of the samples is kept undamaged.
(2) The sample was observed with parallel light. Stopping the polarizer and the analyzer, extracting the polarizer, switching to a bright field imaging mode, observing the surface of the sample by adopting parallel light of a microscope, adjusting the imaging mode of the microscope to be colorful, adjusting the magnification to be 100 times according to needs, and finding a target area to be observed;
(3) the sample was observed using polarized light. Pushing a polarizer and an analyzer into the polarizer to the bottom, switching to a polarized light imaging mode, adjusting the polarizer and the analyzer of the microscope to be in an orthogonal state, and photographing a picture of a target area by adopting orthogonal polarized light, wherein the picture is shown in figure 1;
(4) judging the type of the red substance. Analyzing the color of the surface substance above the steel substrate of the polarized light picture, and if the dark color is shown in the polarized light picture as oxide skin, the red or yellow color is shown in the polarized light picture as corrosion products.
As can be seen from fig. 1, the red substance is composed of both oxide scale and corrosion products, and the red part (relatively bright color) in the figure is the corrosion product, and the dark region is the high-temperature red oxide scale.
Example 2
AH36 ship plate steel produced by a hot rolling process, the thickness of the steel plate is 16mm, and the steel plate is placed in a warehouse for 60 days. The method for distinguishing the types of red substances by using the ZEISS Axio Imager M2M metallographic microscope with a polarizer and an analyzer comprises the following steps:
(1) and (5) preparing a sample. The surface of the red X65 steel was sealed with epoxy resin to maintain the original surface state of the sample without being damaged, and the sample was cut into 30X 16mm by a machine.
(2) The sample was observed with parallel light. Stopping the polarizer and the analyzer, extracting the polarizer, switching to a bright field imaging mode, observing the surface of the sample by adopting parallel light of a microscope, adjusting the imaging mode of the microscope to be colorful, adjusting the magnification to be 200 times according to needs, and finding a target area to be observed;
(3) the sample was observed using polarized light. Pushing a polarizer and an analyzer into the polarizer to the bottom by using the polarizer and the analyzer, switching to a polarized light imaging mode, adjusting the polarizer and the analyzer of the microscope to be in an orthogonal state, and shooting a picture of a target area by adopting orthogonal polarized light, wherein a blue area at the upper part of the picture is epoxy resin, an oxide scale (relatively dark color) and a corrosion product (relatively bright color) are arranged in the middle of the picture, and a black area at the lower part of the picture is a steel substrate;
(4) judging the type of the red substance. Analyzing the color of the surface substance above the steel substrate of the polarized light picture, and if the dark color is shown in the polarized light picture as oxide skin, the red or yellow color is shown in the polarized light picture as corrosion products.
As can be seen from fig. 2, corrosion products appear on the surface of the scale and the steel substrate.
Claims (5)
1. A method of distinguishing red scale from red corrosion products of hot rolled steel, characterized by: the method comprises the following steps:
(1) preparing a sample: cutting hot rolled steel with red surface into single samples, and keeping the surfaces of the samples free of damage;
(2) searching a target area by adopting parallel light: observing a sample by using a microscope with a polarizer and an analyzer, extracting the polarizer during observation, stopping using the polarizer and the analyzer, switching the microscope to a bright field imaging mode, observing the surface or the cross section of the sample by adopting parallel light, adjusting the imaging mode of the microscope to be colored, and adjusting the magnification factor according to needs to find a target area;
(3) observing the target area by adopting polarized light: pushing a polarizer to the bottom of a microscope, starting the polarizer and an analyzer, switching the microscope to a polarized light imaging mode, adjusting the polarizer and the analyzer of the microscope to be in an orthogonal state, and shooting a target area by adopting orthogonal polarized light to obtain a polarized light picture;
(4) and (4) classification: the oxide skin and the corrosion products are distinguished according to different colors of the pictures,
the scale produced by the hot rolled steel at high temperature is amorphous and isotropic, and is in an extinction state under an orthogonal polarization microscope, while the outer layer substance of the corrosion product is crystalline FeOOH and is in a yellow or red bright state under an orthogonal polarization state.
2. The method of differentiating red scale from red corrosion products of hot rolled steel according to claim 1, characterized in that: and (2) cutting the hot rolled steel in the step (1) by adopting flame cutting or mechanical cutting.
3. The method of differentiating red scale from red corrosion products of hot rolled steel according to claim 1, characterized in that: and (2) cutting the hot rolled steel in the step (1) into samples with the length of less than 100mm, the width of less than 100mm and the thickness of less than 30 mm.
4. The method of differentiating red scale from red corrosion products of hot rolled steel according to claim 1, characterized in that: the magnification of the step (2) is 100 times or 200 times.
5. The method of differentiating red scale from red corrosion products of hot rolled steel according to claim 1, characterized in that: the microscope is a metallographic microscope.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005342770A (en) * | 2004-06-04 | 2005-12-15 | Sumitomo Metal Ind Ltd | Method for manufacturing hot-rolled steel sheet |
| CN101012528A (en) * | 2007-01-25 | 2007-08-08 | 鞍钢股份有限公司 | Surface iron scale control method for middle sheet billet continuous casting and rolling steel plate |
| CN103769424A (en) * | 2014-01-08 | 2014-05-07 | 南京钢铁股份有限公司 | Method for controlling red oxide scale on surface of steckel mill steel plate |
| CN106053471A (en) * | 2016-08-04 | 2016-10-26 | 南京钢铁股份有限公司 | Method for showing austenite crystal boundary of micro-alloyed steel in vacuum hot-corrosion condition |
| JP2017200701A (en) * | 2016-05-06 | 2017-11-09 | 株式会社神戸製鋼所 | Manufacturing method of steel material |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103406368B (en) * | 2013-08-16 | 2015-08-05 | 武汉钢铁(集团)公司 | Optimize the milling method of hot rolled sheet metal surface quality |
| CN107790506A (en) * | 2016-08-29 | 2018-03-13 | 王刚 | A kind of Surfaces of Hot Rolled Strip processing method |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005342770A (en) * | 2004-06-04 | 2005-12-15 | Sumitomo Metal Ind Ltd | Method for manufacturing hot-rolled steel sheet |
| CN101012528A (en) * | 2007-01-25 | 2007-08-08 | 鞍钢股份有限公司 | Surface iron scale control method for middle sheet billet continuous casting and rolling steel plate |
| CN103769424A (en) * | 2014-01-08 | 2014-05-07 | 南京钢铁股份有限公司 | Method for controlling red oxide scale on surface of steckel mill steel plate |
| JP2017200701A (en) * | 2016-05-06 | 2017-11-09 | 株式会社神戸製鋼所 | Manufacturing method of steel material |
| CN106053471A (en) * | 2016-08-04 | 2016-10-26 | 南京钢铁股份有限公司 | Method for showing austenite crystal boundary of micro-alloyed steel in vacuum hot-corrosion condition |
Non-Patent Citations (2)
| Title |
|---|
| 热轧Q235B钢板表面红色氧化铁皮检测分析;薛宪营;《新疆钢铁》;20100215;5-7页 * |
| 连铸坯表面氧化铁皮生成特性及其微观结构的研究;豆乃远;《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》;20170315;B023-227 * |
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