CN115201099A - Method for detecting density of corrosion active inclusions in low-alloy marine steel - Google Patents
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Abstract
The invention provides a method for detecting density of corrosion active inclusions in low-alloy marine steel, and relates to the technical field of corrosion resistance evaluation of marine steel. The etching solution adopts acidic or nearly neutral artificial seawater, can well reduce the corrosion behavior of the inclusions in the marine environment, induces the corrosion active inclusions of the steel matrix to generate corrosion pits, and does not react with the inactive inclusions, thereby distinguishing the corrosion active inclusions from the inactive inclusions. Particularly, the formation of stable etching pits can be promoted under the acidic environment, and the etching pits are more regular and obviously convenient for counting statistics. The inclusions in the sample are not completely dissolved or fall off after being soaked in the artificial seawater, and part of the inclusions still remain in the corrosion pit, so that the corrosion active inclusions can be further analyzed. The detection method provided by the invention is simple and easy to operate, has low requirements on detection equipment, has an intuitive test result, and can simply and conveniently distinguish corrosion active inclusions/non-active inclusions and calculate the density of the corrosion active inclusions/non-active inclusions.
Description
Technical Field
The invention relates to the technical field of corrosion resistance evaluation of marine steel, in particular to a method for detecting density of corrosion active inclusions in low-alloy marine steel.
Background
The ocean contains abundant resources, and the development of ocean resources is also more and more emphasized in the countries in recent years. The development of marine resources cannot be realized, and a large amount of marine equipment mostly adopts low alloy steel as a main body material due to the limitation of cost, so the corrosion resistance of the marine steel directly influences the service life of the marine equipment. The inclusions are direct influence factors causing pitting initiation of the marine steel, and meanwhile, researches find that not all the inclusions can induce the pitting initiation, the inclusions have difference in corrosion activity, and only the inclusions with corrosion activity can induce corrosion of a steel matrix. Therefore, the corrosion resistance of the steel is evaluated, the density of the corrosion active inclusions is more accurate than that of the inclusions, and the density of the corrosion active inclusions is an important index for evaluating the quality of the steel.
Chinese patent CN113030143A discloses a method for detecting corrosion activity of inclusions in low alloy steel, which comprises the following steps: placing the polished sample in a full-automatic inclusion analyzer and a field emission scanning electron microscope in sequence to measure the type number and the radius of the inclusions of the sample to be measured; and selecting one inclusion from each type of inclusions and recording the radius of each type of inclusion in turn. Then, the residual stress sigma at the interface of the i-type inclusion and the steel matrix is obtained by combining the measurement results and the physical property parameters of different types of inclusions Ri . If the residual stress σ Ri Greater than the compressive yield strength sigma of low alloy steel s The i-th type inclusions are corrosion-active inclusions, otherwise they are non-corrosion-active inclusions. Although this method can distinguish corrosion active/inactive inclusions, the operation is cumbersome and the requirement for equipment is high.
For another example, chinese patent CN109187322a discloses a corrosion resistance evaluation method of low alloy steel for polar region marine environment, which specifically comprises the following detection steps: (1) grinding and polishing the low alloy steel; (2) placing the polished sample in prepared corrosive liquid for corrosion treatment; (3) and observing under a metallographic microscope, and counting the number of the inclusion pitting sources. Although the corrosion liquid of the method accelerates the corrosion process, the corrosion in the marine environment cannot be well reduced, and the activity of the inclusions cannot be accurately evaluated. Further, the corrosive liquid dissolves or drops inclusions after the sample treatment, and further analysis of corrosion-inducing inclusions is impossible.
Disclosure of Invention
The invention aims to provide a method for detecting the density of corrosion active inclusions in low-alloy marine steel, which is visual, effective, simple and feasible, has low requirements on detection equipment, and can truly reduce the corrosion behavior of inclusions in the marine steel in the marine environment.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides a method for detecting density of corrosion active inclusions in low-alloy marine steel, which comprises the following steps:
soaking a sample to be tested of the low-alloy marine steel into artificial seawater for corrosion to obtain a sample containing pitting characteristics; the artificial seawater per liter solution contains NaCl 15-25 g and Na 2 SO 4 3～5g、NaHCO 3 0.2～0.5g、KCl 0.5～1.0g、MgCl 2 ·6H 2 O 10～15g、CaCl 2 1-2 g of KBr and 0.1-0.2 g of KBr, wherein the pH value of the artificial seawater is 3.5-8.2;
placing the pitting corrosion sample under a metallographic microscope, counting the total number of corrosion pits in the field area, and calculating the density of the corrosion active inclusions according to formula 1: ρ = a/S formula 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
Preferably, the soaking time is 15-25 min.
Preferably, the total number of pits within the statistical field of view area includes: shooting n metallographs, and counting the total number of pits in the n metallographs; there is no overlapping area between the n metallographs.
Preferably, before the sample to be tested of the low alloy marine steel is soaked in the artificial seawater, the method further comprises the steps of sequentially grinding, polishing and cleaning the sample to be tested.
Preferably, the polishing comprises sequentially polishing with 400-mesh, 800-mesh, 1500-mesh, 2500-mesh and 5000-mesh silicon carbide sandpaper step by step.
Preferably, the pH value of the artificial seawater is 4-6.5.
The invention provides a method for detecting density of corrosion active inclusions in low-alloy marine steel, which comprises the following steps: soaking a sample to be tested of the low-alloy marine steel into artificial seawater for corrosion to obtain a sample containing pitting characteristics; the artificial seawater per liter solution contains NaCl 15-25 g and Na 2 SO 4 3～5g、NaHCO 3 0.2～0.5g、KCl 0.5～1.0g、MgCl 2 ·6H 2 O 10～15g、CaCl 2 1-2 g of KBr and 0.1-0.2 g of KBr, wherein the pH value of the artificial seawater is 3.5-8.2; placing the pitting corrosion sample under a metallographic microscope, counting the total number of corrosion pits in the field area, and calculating the density of the corrosion active inclusions according to formula 1: ρ = a/S formula 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
The etching solution adopts acidic or near-neutral artificial seawater, can well reduce the corrosion behavior of the inclusions in the marine environment, induces the corrosion active inclusions of the steel matrix to generate corrosion pits, and does not react with the inactive inclusions, thereby distinguishing the corrosion active inclusions from the inactive inclusions. The formation of stable etching pits can be promoted under the acidic environment, and the etching pits are more regular and more obvious, so that counting statistics is facilitated.
The inclusions in the sample are not completely dissolved or fall off after being subjected to artificial seawater corrosion treatment, and part of the inclusions still remain in the corrosion pit, so that the corrosion active inclusions can be further analyzed.
The detection method provided by the invention is simple and easy to operate, has low requirements on detection equipment, has an intuitive test result, and can simply and conveniently distinguish corrosion active inclusions/non-active inclusions and calculate the density of the corrosion active inclusions/non-active inclusions.
Drawings
FIG. 1 is a schematic diagram of marine steel plate sampling;
FIG. 2 is a metallographic microscope photograph showing statistics of density of corrosion-active inclusions in a marine steel sheet S420 according to example 1;
FIG. 3 is another metallographic microscope photograph showing statistics of densities of corrosion-active inclusions in a marine steel sheet S420 according to example 1;
FIG. 4 is a metallographic microscope image of statistics of density of corrosion active inclusions in the marine steel plate FH550 according to example 2;
FIG. 5 is another metallographic microscope photograph showing statistics of density of corrosion-active inclusions in the marine steel plate FH550 according to example 2;
FIG. 6 is a metallographic microscope photograph showing statistics of density of corrosion active inclusions in a marine steel sheet S420 according to example 3;
FIG. 7 is another metallographic microscope photograph showing statistics of density of corrosion-active inclusions in a marine steel sheet S420 according to example 3;
FIG. 8 is a bar graph showing the results of the tests of inclusion density, corrosion-active inclusion density and corrosion rate of the marine steel sheets of examples 1 and 2;
FIG. 9 is a metallographic microscope photograph showing statistics of density of corrosion-active inclusions in a marine steel sheet S420 according to comparative example 1.
Detailed Description
The invention provides a method for detecting density of corrosion active inclusions in low-alloy marine steel, which comprises the following steps:
soaking a sample to be tested of the low-alloy marine steel into artificial seawater for corrosion to obtain a sample with pitting corrosion characteristics; the artificial seawater per liter solution contains NaCl 15-25 g and Na 2 SO 4 3～5g、NaHCO 3 0.2～0.5g、KCl 0.5～1.0g、MgCl 2 ·6H 2 O 10～15g、CaCl 2 1-2 g of KBr and 0.1-0.2 g of KBr, wherein the pH value of the artificial seawater is 3.5-8.2;
placing the pitting corrosion sample under a metallographic microscope, counting the total number of corrosion pits in the field area, and calculating the density of the corrosion active inclusions according to formula 1: ρ = a/S formula 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
The invention preferably refers to GB/T10561-2005A microscopic examination method for a standard grade chart for measuring the content of non-metallic inclusions in steel intercepts a sample to be measured on low-alloy marine steel to be measured, and if the detection target is a specific area of the marine steel, the intercepting position and the size of the sample can be defined by user. In the present invention, the detection area is preferably larger than 100mm 2 。
The invention has no special requirements on the chemical composition of the low-alloy marine steel, and the low-alloy marine steel with the composition well known in the field is suitable for the low-alloy marine steel. In the embodiment of the present invention, specifically, S420 or FH550.
Before a sample to be tested of the low-alloy marine steel is soaked in artificial seawater, the method preferably further comprises the steps of sequentially grinding, polishing and cleaning the sample to be tested.
In the present invention, the polishing preferably comprises polishing stepwise sequentially with 400 mesh, 800 mesh, 1500 mesh, 2500 mesh and 5000 mesh silicon carbide sandpaper. Every time the sand paper is changed, the invention preferably rotates the sample to be tested by 90 degrees to form a vertical direction with the old grinding scar, and the sample is ground in the direction until the old grinding scar disappears and the new grinding scar is uniform. The invention utilizes the grinding to lead the surface of the sample to be smooth and flat, thus being convenient for the next step of polishing. The present invention does not require special polishing, and can be accomplished by any polishing process known in the art. The invention utilizes polishing to make the corrosion pit more obvious and is convenient for counting. In the present invention, the washing preferably includes washing with acetone, deionized water, and alcohol in this order. The invention removes impurities, grease and other dirt attached to the surface of the sample in the polishing process by cleaning, and reduces the interference of the impurities, grease and other dirt on the experiment.
After cleaning, the cleaned sample is preferably dried by blowing, and then is soaked in artificial seawater for corrosion.
In the invention, each liter of solution of the artificial seawater contains 15-25 g of NaCl and Na 2 SO 4 3～5g、NaHCO 3 0.2～0.5g、KCl 0.5～1.0g、MgCl 2 ·6H 2 O 10～15g、CaCl 2 1-2 g of KBr and 0.1-0.2 g of KBr, preferably, the artificial seawater contains 20-25 g of NaCl and Na in each liter of solution 2 SO 4 3.5～4.5g、NaHCO 3 0.2～0.3g、KCl 0.6～0.8g、MgCl 2 ·6H 2 O 11～13g、CaCl 2 1.1-1.5 g, KBr 0.1-0.2 g; more preferably 24.53g of NaCl and Na 2 SO 4 4.09g、NaHCO 3 0.20g、KCl 0.7g、MgCl 2 ·6H 2 O 11.1g、CaCl 2 1.16g, KBr 0.1g; the pH of the artificial seawater is preferably 3.5 to 8.2, more preferably 4 to 6.5, and even more preferably 4. The invention preferably adopts hydrochloric acid to adjust the pH value of the artificial seawater to a target range. The invention has no special requirements on the preparation process of the artificial seawater, and the artificial seawater is prepared by directly dissolving all components into water and then regulating the pH value by using hydrochloric acid.
The invention has no special requirement on the consumption of the artificial seawater, and can completely immerse the sample to be tested. In the present invention, the soaking time is preferably 15 to 25min, and more preferably 18 to 22min. According to the method, the artificial seawater with a specific composition is adopted to soak the sample to be tested, so that the corrosion behavior of the inclusion in the marine environment can be well reduced, the steel matrix is induced to be corroded to generate corrosion pits, and the inactive inclusion does not react, so that the corrosive active inclusion and the inactive inclusion are distinguished. In addition, the acid environment can promote the formation of stable etching pits, and the etching pits are more regular and obviously convenient for counting statistics. The inclusions in the sample are not completely dissolved or fall off after being subjected to artificial seawater corrosion treatment, and part of the inclusions still remain in the corrosion pit, so that the corrosion active inclusions can be further analyzed.
After soaking, the invention preferably takes out the sample, cleans the sample by alcohol and dries the sample by air cooling to obtain the sample containing the pitting characteristic.
After a sample containing the pitting characteristics is obtained, the sample containing the pitting characteristics is placed under a metallographic microscope, the total number of pits in a field area is counted, and the density of corrosion active inclusions is calculated according to the formula 1: ρ = a/S formula 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
In the present invention, the magnification of the metallographic microscope is preferably based on the fact that the corrosion pits can be distinguished, which is not particularly required by the present invention. In the present invention, the total number of pits in the statistical field of view area preferably includes: and (4) shooting n metallographic pictures, and counting the total number of the etching pits in the n metallographic pictures.
When taking metallographs, the present invention preferably ensures that the boundaries between different pictures overlap and there is no overlapping area, thereby facilitating statistics on the number of corrosion pits. In the invention, when the number of the etching pits is counted, the etching pits with the center positioned on the boundary are only counted on the left boundary and the upper boundary, or only counted on the right boundary and the lower boundary, so as to avoid repeated counting.
In the present invention, the number of etching pits in the 1 st metallograph is represented as a 1 The corresponding field area is denoted as S 1 (ii) a The number of pits in the 2 nd metallograph is denoted as a 2 The corresponding field area is marked as S 2 (ii) a And analogizing in turn, the number of the etching pits in the nth metallographic picture is recorded as a n The corresponding field area is marked as S n (ii) a The total number of pits in the field area
Area of field of view
The density of corrosion active inclusions is calculated according to formula 1: ρ = a/S formula 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
The detection method provided by the invention is simple and easy to operate, has low requirements on detection equipment, has an intuitive test result, and can simply and conveniently distinguish corrosion active inclusions/non-active inclusions and calculate the density of the corrosion active inclusions/non-active inclusions.
The method for detecting the density of corrosion-active inclusions in low-alloy marine steel according to the present invention will be described in detail with reference to examples, but the scope of the present invention is not to be construed as being limited thereto.
Example 1
A method for detecting density of corrosion active inclusions in low-alloy marine steel comprises the following steps:
step one, cutting a sample with the size of 10mm multiplied by 5mm by a sampling method of a low-alloy marine steel plate S420 to be tested according to GB/T10561-2005 microscopic inspection method for determination standard grade chart of content of non-metallic inclusions in steel, wherein the sampling schematic diagram is shown in attached figure 1.
And step two, gradually polishing the sample to be tested by using 400-mesh, 800-mesh, 1500-mesh, 2500-mesh and 5000-mesh silicon carbide abrasive paper, rotating the sample by 90 degrees to form a vertical direction with the old grinding mark each time the abrasive paper is replaced, polishing in the direction until the old grinding mark disappears and the new grinding mark is uniform, then sequentially cleaning the polished sample by using acetone, deionized water and alcohol, and drying the sample to be tested.
Step three, preparing artificial seawater with pH =4, wherein each liter of solution contains 24.53g of NaCl and Na 2 SO 4 4.09g、NaHCO 3 0.2g、KCl 0.7g、MgCl 2 ·6H 2 O 11.1g、CaCl 2 1.16g and 0.1g of KBr, and the pH value of the artificial seawater is adjusted to 4 by hydrochloric acid after preparation.
And step four, placing the sample to be tested of S420 in artificial seawater with pH =4, soaking for 20min, taking out, cleaning with alcohol, and drying with cold air.
And fifthly, placing the soaked S420 sample under a metallographic microscope for observation, continuously shooting 80 photos under a field of view of 100 times, and counting the number of inclusion-induced pits in each photo, wherein the two metallographic photos are shown in figures 2 and 3, so that the total number of the inclusion pits is obtained
100 times field area S of the metallographic microscope 100 ＝0.9454mm 2 And finally, calculating the density rho of the corrosion active inclusion:
ρ = 157/(80 × 0.9454) mm 2 =2 pieces/mm 2
Finally obtaining the corrosion active inclusion density of 2/mm in S420 steel 2 。
Example 2
A statistical method for density of corrosion active inclusions in low-alloy marine steel comprises the following steps:
step one, cutting a sample with the size of 10mm multiplied by 5mm in the central area of a low-alloy marine steel plate FH550 to be measured along the rolling direction.
And step two, gradually polishing the sample to be tested by using 400-mesh, 800-mesh, 1500-mesh, 2500-mesh and 5000-mesh silicon carbide abrasive paper, rotating the sample by 90 degrees to form a vertical direction with the old grinding marks every time the silicon carbide abrasive paper is replaced, polishing in the direction until the old grinding marks disappear and new grinding marks are uniform and consistent, and finally polishing. And cleaning the polished sample by using acetone, deionized water and alcohol in sequence, and drying to be tested.
Step three, preparing artificial seawater with pH =4, wherein each liter of solution contains 24.53g of NaCl and Na 2 SO 4 4.09g、NaHCO 3 0.2g、KCl 0.7g、MgCl 2 ·6H 2 O 11.1g、CaCl 2 1.16g and 0.1g of KBr, and the pH value of the artificial seawater is adjusted to 4 by hydrochloric acid after preparation.
And step four, placing the sample to be tested FH550 in artificial seawater with pH =4, soaking for 20min, taking out, cleaning with alcohol, and drying with cold air.
And fifthly, placing the soaked FH550 sample under a metallographic microscope for observation, continuously shooting 20 photos under a field of view of 50 times, and counting the number of inclusion pits in each photo, wherein the two metallographic photos are shown in figures 4 and 5, so that the total number of the inclusion pits is sigma a i =756 and 50 times of field area S of metallographic microscope 50 ＝3.782mm 2 And finally, calculating the density rho of the corrosion active inclusion:
ρ = 756/(20 × 3.782) mm 2 =10 pieces/mm 2
The density of the corrosive active inclusion in FH550 is 10/mm 2 。
Example 3
A method for detecting density of corrosion active inclusions in low-alloy marine steel comprises the following steps:
step one, cutting a sample with the size of 10mm multiplied by 5mm by a sampling method of a low-alloy marine steel plate S420 to be tested according to GB/T10561-2005 microscopic inspection method for determination standard grade chart of content of non-metallic inclusions in steel, wherein the sampling schematic diagram is shown in attached figure 1.
And step two, gradually polishing the sample to be tested by using 400-mesh, 800-mesh, 1500-mesh, 2500-mesh and 5000-mesh silicon carbide abrasive paper, rotating the sample by 90 degrees to form a vertical direction with the old grinding mark each time the abrasive paper is replaced, polishing in the direction until the old grinding mark disappears and the new grinding mark is uniform, then sequentially cleaning the polished sample by using acetone, deionized water and alcohol, and drying the sample to be tested.
Step three, preparing artificial seawater with pH =8.2, wherein each liter of solution contains 24.53g of NaCl and Na 2 SO 4 4.09g、NaHCO 3 0.2g、KCl 0.7g、MgCl 2 ·6H 2 O 11.1g、CaCl 2 1.16g and 0.1g of KBr, and the pH value of the artificial seawater is adjusted to 8.2 by NaOH after preparation.
And step four, placing the sample to be tested S420 in artificial seawater with pH =8.2 for soaking for 20min, taking out, cleaning with alcohol, and drying with cold air.
And fifthly, placing the soaked S420 sample under a metallographic microscope for observation, continuously shooting 80 pictures under a field of view of 100 times, and counting the number of inclusion-induced pits in each picture to obtain the total number of the inclusion pits
100 times field area S of metallographic microscope 100 ＝0.9454mm 2 And finally, calculating the density rho of the corrosion active inclusion:
ρ = 295/(80 × 0.9454) mm 2 =4 pieces/mm 2
Finally obtaining the corrosion active inclusion density of 4/mm in S420 steel 2 . However, the characteristic morphology of the corrosion active inclusion pits in the environment is not obvious as shown in fig. 6 and 7, and identification errors easily occur in the statistical process. Therefore, the pH of the artificial seawater used for statistics of the density of corrosion-active inclusions in S420 steel is preferably 4.0, as compared with that of example 1.
And (3) verifying the accuracy:
as shown in FIG. 8, the inclusion (including active and inactive) density of 13 inclusions/mm in S420 of example 1 was measured by an inclusion analyzer (ZISS, EVO18+ X-MAX 80) 2 >2 pieces/mm 2 Example 2 inclusion in FHS550 (bag)Active and inactive) density of 29 pieces/mm 2 >10 pieces/mm 2 . The density sequence of the active inclusions of the two steels is consistent with the density sequence of the inclusions, which shows that the calculation of the density of the active inclusions accords with the rule. And the artificial seawater immersion experiment for 7 days proves that the initial corrosion rate of S420 is 0.47mm/a, the initial corrosion rate of FH550 is 1.21mm/a, which is far greater than S420, and as the density of corrosion active inclusions is positively correlated with the corrosion activity of steel, namely the greater the density of active inclusions, the greater the corrosion rate of steel, the sizes of the corrosion rates of S420 and FH550 are consistent with the statistical result of the density of corrosion active inclusions.
Comparative example 1
The only difference from example 1 is that the pH of the artificial seawater is adjusted to 10 with NaOH.
The soaked S420 sample is placed under a metallographic microscope for observation, and a metallographic photograph is shown in FIG. 9, so that the field of view is disordered, the characteristic pits cannot be distinguished, and statistics cannot be carried out.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.
Claims (6)
1. A method for detecting density of corrosion active inclusions in low-alloy marine steel is characterized by comprising the following steps:
soaking a sample to be tested of the low-alloy marine steel into artificial seawater for corrosion to obtain a sample containing pitting characteristics; the artificial seawater per liter solution contains NaCl 15-25 g and Na 2 SO 4 3～5g、NaHCO 3 0.2～0.5g、KCl 0.5～1.0g、MgCl 2 ·6H 2 O 10～15g、CaCl 2 1-2 g of KBr and 0.1-0.2 g of KBr, wherein the pH value of the artificial seawater is 3.5-8.2;
placing the pitting corrosion sample under a metallographic microscope, counting the total number of corrosion pits in the field area, and calculating the density of the corrosion active inclusions according to formula 1: ρ = a/S equation 1; in the formula 1, ρ is the density of the corrosion-active inclusions, a is the total number of corrosion pits in the field area, and S is the field area.
2. The detection method according to claim 1, wherein the soaking time is 15 to 25min.
3. The inspection method of claim 1, wherein said counting the total number of pits within the field of view area comprises: shooting n metallographs, and counting the total number of pits in the n metallographs; there is no overlapping area between the n metallographs.
4. The detection method according to claim 1, wherein before the sample of the low alloy marine steel is soaked in the artificial seawater, the method further comprises sequentially grinding, polishing and cleaning the sample.
5. The detection method according to claim 4, wherein the grinding comprises grinding sequentially with 400 mesh, 800 mesh, 1500 mesh, 2500 mesh and 5000 mesh silicon carbide sandpaper.
6. The method according to claim 1, wherein the artificial seawater has a pH of 4 to 6.5.
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Citations (3)
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|---|---|---|---|---|
| US20090126492A1 (en) * | 2005-05-10 | 2009-05-21 | Kaiko Sato | Method for evaluating reliability of steel and high-relaibility steel obtained by the same |
| CN113030143A (en) * | 2021-02-26 | 2021-06-25 | 武汉科技大学 | Method for detecting corrosion activity of inclusions in low alloy steel |
| CN113390775A (en) * | 2020-03-14 | 2021-09-14 | 上海梅山钢铁股份有限公司 | Method for detecting macroscopic corrosion resistance of coating of cold-rolled electroplated tin steel plate |
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| US20090126492A1 (en) * | 2005-05-10 | 2009-05-21 | Kaiko Sato | Method for evaluating reliability of steel and high-relaibility steel obtained by the same |
| CN113390775A (en) * | 2020-03-14 | 2021-09-14 | 上海梅山钢铁股份有限公司 | Method for detecting macroscopic corrosion resistance of coating of cold-rolled electroplated tin steel plate |
| CN113030143A (en) * | 2021-02-26 | 2021-06-25 | 武汉科技大学 | Method for detecting corrosion activity of inclusions in low alloy steel |
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| CHAO LIU 等: "New insights into the mechanism of localised corrosion induced by TiN-containing inclusions in high strength low alloy steel", JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY, vol. 124, 25 March 2022 (2022-03-25), pages 141 - 148 * |
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