Semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors

Abstract

The magnesium alloy corrosion inhibitor semi-quantitative high-throughput evaluation method disclosed by the embodiment of the application comprises the following steps: forming small holes with open cavities containing corrosion inhibitors in an array on the surface of a magnesium alloy; injecting different corrosion inhibitors into the small holes in the array; allowing the corrosion inhibitors to react with the magnesium alloy under a set condition; taking a vertical photograph under side light irradiation conditions after the reaction ends, to obtain an image containing the corrosion areas in the small holes; identifying the corrosion areas in the obtained image, to obtain image information of each corrosion area; and evaluating the corrosion effect according to the image information. The evaluation method can simultaneously measure corrosion inhibitors of a large scale, avoids large-scale experimental trial and error, and improves efficiency; parallel measurement of the corrosion inhibitors at different positions on the same magnesium alloy surface can avoid system errors caused by different magnesium alloy samples; and vertical photographing under side light irradiation conditions can simultaneously measure the corrosion rate and the local corrosion degree of the magnesium alloy.

Description

Technical Field

[0001] This invention belongs to the field of metal corrosion protection technology, specifically relating to a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors. Background Technology

[0002] Magnesium and magnesium alloys possess unique advantages in lightweight structural materials and biodegradable medical metal materials. However, the potential difference between the second phase and impurities in magnesium alloys and the magnesium matrix exacerbates localized corrosion, leading to a decrease in corrosion resistance. This problem significantly limits the widespread application of magnesium and magnesium alloys. Corrosion inhibitors are an effective means of corrosion prevention; corrosion inhibitors react with magnesium... 2+ Inorganic substances that form insoluble complexes or react to generate dense corrosion products can effectively reduce the corrosion rate of magnesium alloys, or adsorb onto the surface of the magnesium matrix to isolate the matrix from the corrosive medium, or selectively adsorb onto certain second-phase surfaces to weaken the tendency of magnesium alloys to undergo galvanic corrosion, thereby slowing down the corrosion process of the metal.

[0003] Many corrosion inhibitors for magnesium alloys have been reported, but most studies focus on the effect of the inhibitors on the corrosion rate of magnesium alloys, and fail to fully evaluate the inhibitors in light of the actual service requirements of magnesium alloys. The screening of corrosion inhibitors mainly relies on large-scale experimental trial and error, which is inefficient. Traditional experimental methods such as corrosion weight loss, hydrogen evolution, and electrochemical testing are mainly used, which are resource-intensive, have low testing efficiency, and have a small screening range.

[0004] For magnesium alloys, whether used as lightweight structural materials or biodegradable medical metals, they need to maintain sufficient mechanical strength to withstand corresponding loads during service. However, during long-term service in corrosive environments, the mechanical load-bearing capacity of magnesium alloys decreases as corrosion occurs. Studies have found that changes in the mechanical properties of magnesium alloys are not directly related to the corrosion rate, but rather to the mechanical integrity of magnesium alloys and the degree of localized corrosion. The potential difference between the second phase, impurities, and the magnesium matrix in magnesium alloys leads to severe localized corrosion. Under stress, microcracks formed around the corrosion pits cause localized stress concentration, becoming the source of crack propagation, resulting in a significant decrease in the mechanical properties of magnesium alloys and premature failure during service. Therefore, relying solely on the corrosion rate to evaluate the effectiveness of magnesium alloy corrosion inhibitors is inaccurate; the mechanical integrity of magnesium alloys under the action of corrosion inhibitors should be considered as an important indicator for screening and evaluating corrosion inhibitors. However, currently, there is no method to assess the localized corrosion behavior of magnesium alloys under the action of corrosion inhibitors, so as to achieve a comprehensive evaluation of magnesium alloy corrosion inhibitors. Summary of the Invention

[0005] In view of this, some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, including:

[0006] An array of small holes is formed on the surface of the magnesium alloy, and the small holes have open cavities to accommodate corrosion inhibitors;

[0007] Different corrosion inhibitors were injected into the array of small holes;

[0008] The corrosion inhibitor injected into the small hole reacts with the magnesium alloy under set conditions;

[0009] After the corrosion reaction was completed, the magnesium alloy surface was photographed vertically under side lighting conditions to obtain an image containing the corrosion area in the array of pinholes.

[0010] The corroded areas in the obtained images are identified to obtain image information for each corroded area in the array of pinholes;

[0011] The corrosion effect is evaluated based on the image information of the corroded area.

[0012] Furthermore, some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, in which image information includes the maximum brightness, minimum brightness, average brightness, brightness standard deviation, and area percentage of corrosion regions at different brightness levels.

[0013] Some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors. The RGB value ratio of corrosion products in the corrosion area is in the range of 1 to 1.3:1 to 1.2:1. The average brightness and brightness standard deviation are used to evaluate the inhibitor's effect on the corrosion rate and local corrosion degree of magnesium alloys.

[0014] In some embodiments of the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, if the RGB value ratio of corrosion products in the corrosion area is not within the range of 1-1.3:1-1.2:1, then corrosion inhibitors that can inhibit local corrosion of magnesium alloys are first screened according to the standard deviation of brightness. Then, the height difference between the corrosion interface and the uncorroded interface is observed using a laser confocal microscope to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate.

[0015] Some embodiments of the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors also include calculating the corrosion inhibition capacity and corrosion factor using image information, with the calculation formula as follows:

[0016]

[0017] Where IP represents corrosion inhibition capability, PF represents corrosion factor, and L represents corrosion resistance. a For average brightness, L M For maximum brightness, L m This is the minimum brightness.

[0018] Some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, wherein the corrosion reaction is carried out on a testing device, which includes a magnesium alloy and a transparent polymer plate fixedly connected to the surface of the magnesium alloy. The transparent polymer plate has an array of through holes; the surface of the magnesium alloy and the through holes form an open cavity for accommodating the corrosion inhibitor.

[0019] Some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, wherein the transparent polymer sheet is an acrylic sheet.

[0020] Some embodiments disclose a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, which uses ImageJ to identify the black-and-white contrast of an image to obtain image information.

[0021] The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors disclosed in this invention can simultaneously measure corrosion inhibitors on a large scale, avoiding large-scale experimental trial and error and significantly improving efficiency. It can initially select corrosion inhibitors that can effectively slow down the corrosion rate of magnesium alloys or significantly inhibit localized corrosion behavior, enriching and improving the magnesium alloy corrosion inhibitor database. Parallel measurements of corrosion inhibitors at different locations on the same magnesium alloy surface can avoid measurement system errors caused by differences in magnesium alloy samples. Vertical photography under side lighting conditions can simultaneously measure the corrosion rate and localized corrosion degree of magnesium alloys. Adding the assessment of the corrosion inhibitor's ability to inhibit localized corrosion during the screening and evaluation of magnesium alloy corrosion inhibitors will help to more comprehensively evaluate the effect of corrosion inhibitors. Attached Figure Description

[0022] Figure 1 Flowchart of a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors disclosed in some embodiments;

[0023] Figure 2 Image of experimental samples for semi-quantitative high-throughput evaluation of magnesium alloy corrosion inhibitors disclosed in Example 1;

[0024] Figure 3 Image of experimental samples for semi-quantitative high-throughput evaluation of magnesium alloy corrosion inhibitors disclosed in Example 2;

[0025] Figure 4 Morphology of the semi-quantitative high-throughput evaluation product of the magnesium alloy corrosion inhibitor disclosed in Example 2;

[0026] Figure 5 Image of experimental samples for semi-quantitative high-throughput evaluation of magnesium alloy corrosion inhibitors disclosed in Example 3. Detailed Implementation

[0027] The term "embodiment" used herein, as an example, is not necessarily to be construed as superior to or better than other embodiments. Performance testing in these embodiments of the invention, unless otherwise specified, employs conventional testing methods in the art. It should be understood that the terminology used in these embodiments is merely for describing particular implementations and is not intended to limit the scope of the disclosure of these embodiments.

[0028] Unless otherwise stated, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the embodiments of this invention pertain; other experimental methods and technical means not specifically noted in the embodiments of this invention refer to experimental methods and technical means commonly used by one of ordinary skill in the art.

[0029] The terms “basic” and “approximately” used in this document are to describe small fluctuations. For example, they can mean less than or equal to ±5%, such as less than or equal to ±2%, such as less than or equal to ±1%, such as less than or equal to ±0.5%, such as less than or equal to ±0.2%, such as less than or equal to ±0.1%, such as less than or equal to ±0.05%. Numerical data presented or expressed in range format in this document are used for convenience and brevity only, and should therefore be flexibly interpreted to include not only the explicitly listed values ​​that define the range, but also all independent values ​​or subranges contained within that range. For example, a numerical range of “1–5%” should be interpreted to include not only the explicitly listed values ​​from 1% to 5%, but also the independent values ​​and subranges within the indicated range. Thus, this numerical range includes independent values ​​such as 2%, 3.5%, and 4%, and subranges such as 1%–3%, 2%–4%, and 3%–5%, etc. This principle also applies to ranges that list only one value. Furthermore, this interpretation applies regardless of the width of the range or the characteristics described.

[0030] In this document, including in the claims, conjunctions such as "comprising," "including," "with," "having," "containing," "involving," and "accommodating" are understood to be open-ended, meaning "including but not limited to." Only the conjunctions "consisting of" and "composed of" are closed conjunctions.

[0031] To better illustrate the content of this invention, numerous specific details are provided in the following detailed embodiments. Those skilled in the art should understand that the invention can be practiced even without certain specific details. In the embodiments, some methods, means, instruments, and devices well-known to those skilled in the art are not described in detail, in order to highlight the main points of the invention.

[0032] Without conflict, the technical features disclosed in the embodiments of the present invention can be combined arbitrarily, and the resulting technical solution belongs to the content disclosed in the embodiments of the present invention.

[0033] In some embodiments, the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors includes:

[0034] An array of small holes is formed on the surface of a magnesium alloy. Each small hole has an open cavity for accommodating a corrosion inhibitor. Typically, the corrosion reaction between the magnesium alloy surface and the corrosion inhibitor can be performed on a testing device. The testing device includes a magnesium alloy and a transparent polymer sheet fixedly connected to the surface of the magnesium alloy. The transparent polymer sheet has an array of through holes. The magnesium alloy surface and the through holes form an open cavity for accommodating the corrosion inhibitor. In some embodiments, the transparent polymer sheet is an acrylic sheet.

[0035] Different corrosion inhibitors are injected into the array of small holes; typically, different corrosion inhibitors can be corrosive solutions of different types, concentrations, and compositions that can react with magnesium alloys to cause corrosion.

[0036] The corrosion inhibitor injected into the pinhole reacts with the magnesium alloy under set conditions; typically, the set conditions can be set to simulate the environmental conditions of the magnesium alloy under actual use conditions, such as a certain temperature, humidity, and ambient atmosphere.

[0037] After the corrosion reaction is completed, the magnesium alloy surface is photographed vertically under side lighting conditions to obtain images containing the corrosion areas in the array of pinholes. Usually, after the corrosion reaction is carried out under set environmental conditions for a set time, the expected corrosion effect can be obtained to meet the needs of subsequent photographic analysis.

[0038] Typically, corrosion products deposited on the surface of magnesium alloys appear white under the refraction and diffuse reflection of light. The higher the corrosion rate of the magnesium alloy and the thicker the corrosion products, the more obvious the white color of the corrosion products appears under side lighting. Under the same lighting conditions, uncorroded areas appear black due to the lack of light reflection. This effectively avoids misjudging the corrosion inhibition effect due to the formation of a dark precipitate protective layer by some corrosion inhibitors reacting with the magnesium alloy. Since corrosion products accumulate around the corrosion sites when localized corrosion occurs in magnesium alloys, photographs taken vertically under side lighting can directly reflect the influence of corrosion inhibitors on the localized corrosion behavior of magnesium alloys.

[0039] The eroded areas in the obtained image are identified to obtain image information for each eroded area in the array of pinholes. Generally, image processing methods are used to process the image. For example, ImageJ can be used to identify the black and white contrast of the image to obtain image information. Typically, the image information includes the maximum brightness, minimum brightness, average brightness, brightness standard deviation, and area percentage of the eroded area at different brightness levels.

[0040] The corrosion inhibition capacity and corrosion factor can be further calculated using image information. The calculation formula is as follows:

[0041]

[0042] Where IP represents corrosion inhibition capability, PF represents corrosion factor, and L represents corrosion resistance. a For average brightness, L M Lm represents the maximum brightness, and Lm represents the minimum brightness. Generally, the larger the IP value, the faster the corrosion rate of the alloy in the solution; the larger the PF value, the more severe the local corrosion of the alloy.

[0043] The corrosion effect is evaluated based on the image information of the corroded area. Generally, the evaluation method is determined based on the RGB value ratio characteristics of the corrosion products in the corroded area. If the RGB value ratio is within the range of 1–1.3:1–1.2:1, the average brightness and brightness standard deviation are used to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate and local corrosion degree of the magnesium alloy. If the RGB value ratio of the corrosion products is not within the range of 1–1.3:1–1.2:1, the inhibitors that can inhibit local corrosion of the magnesium alloy are first screened according to the brightness standard deviation, and then the height difference between the corroded interface and the uncorroded interface is observed using a laser confocal microscope to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate. The following examples further illustrate the technical details.

[0044] Example 1

[0045] In Example 1, the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors includes:

[0046] (1) Preparation of micropore parallel array test device: ZE21B magnesium alloy sample and acrylic sheet are bonded together and connected and fixed with silicone sealing plate. The array of through holes on the acrylic sheet and the surface of magnesium alloy sample form an open cavity to accommodate corrosion inhibitor; wherein, the through holes form a 3×4 array.

[0047] (2) Prepare 0.05wt.% NaCl, 0.5wt.% NaCl and 5wt.% NaCl solutions as corrosion inhibitors, and pure water as a control; in the through holes of the 3×4 array, every three holes are grouped together and the same corrosion inhibitor is injected;

[0048] (3) Inject a certain amount of the prepared slow-release agent into each through hole, keep it in a constant humidity chamber for 24 hours, and after soaking, remove the corrosion inhibitor and dry the sample.

[0049] (4) Take a vertical photograph of the etched sample under side lighting conditions;

[0050] Figure 2 In the image, (a) shows the sample in the testing device after the corrosion reaction is complete; (b) shows the sample as captured by the image acquisition device. Figure 2As shown in (b), the RGB values ​​of 0.5 wt.% NaCl are 97:92:81, and the RGB value ratio is in the range of 1 to 1.3:1 to 1.2:1. The average brightness and brightness standard deviation are used to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate and local corrosion of magnesium alloy. Figure 2 The analysis results of the corrosion area in (b) are shown in Table 1. It can be seen that with the increase of NaCl concentration, the average brightness, IP, standard deviation and PF all show an upward trend, indicating that the corrosion rate and local corrosion tendency of magnesium alloy increase with the increase of NaCl concentration. In addition, the corrosion behavior of ZE21B magnesium alloy in NaCl solution is characterized by large-area uniform corrosion and obvious local corrosion. When the NaCl concentration increases, the area of ​​local corrosion also expands.

[0051] Table 1 Comparison of IP, PF, standard deviation, and average brightness of NaCl solutions of different concentrations

[0052]

[0053] In Example 1, the average brightness and standard deviation were used to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate and localized corrosion of magnesium alloy. Average brightness reflects the overall brightness within the corroded area; a higher brightness value means a more pronounced white color in the corroded area, indicating a faster corrosion rate of the magnesium alloy. The standard deviation reflects the uniformity of brightness within the corroded area; a larger standard deviation indicates more severe localized corrosion. Compared to pure water and NaCl solution, the average brightness and standard deviation were lower, indicating that the solution had an inhibitory effect on the corrosion rate and localized corrosion of the magnesium alloy. The closer the average brightness and standard deviation were to pure water, the better the inhibitor's effect.

[0054] Example 2

[0055] In Example 2, the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors includes:

[0056] (1) Preparation of micropore parallel array test device: ZE21B magnesium alloy sample and acrylic plate are bonded together and connected and fixed with silicone sealing plate. The array of through holes on the acrylic plate and the surface of magnesium alloy sample form an open cavity to accommodate corrosion inhibitor; wherein, the through holes form a 3×3 array.

[0057] (2) Schiff base and 3,4-2-hydroxybenzaldehyde with a concentration of 50 mmol / L were prepared in a 0.5 wt.% NaCl solution as corrosion inhibitors, and a 0.5 wt.% NaCl solution was used as a control. In the through holes of the 3×3 array, every three holes were grouped together and the same corrosion inhibitor was injected.

[0058] (3) Inject a certain amount of the prepared corrosion inhibitor into each well, keep it in a constant humidity chamber for 24 hours, and after soaking, remove the corrosion inhibitor and dry the sample.

[0059] (4) Take a vertical photograph of the etched sample under side lighting conditions;

[0060] Figure 3 In the image, (a) shows the sample in the testing device after the corrosion reaction is complete; (b) shows the sample as captured by the image acquisition device. Figure 3 As shown in (b), the RGB ratio of 3,4-2-hydroxybenzaldehyde is 192:172:128, and the RGB value ratio is not within the range of 1-1.3:1-1.2:1. First, ImageJ was used to analyze the standard deviation and power factor (PF) of the corrosion circle in the image, as shown in Table 2. Compared with NaCl solution, the standard deviation and PF of Schiff base decreased significantly, indicating that Schiff base can significantly inhibit local corrosion of magnesium alloy. Furthermore, the IP value of Schiff base is lower than that of NaCl solution, indicating that Schiff base can effectively slow down the corrosion rate of magnesium alloy. Then, laser confocal microscopy was used to verify the height difference between the corroded and uncorroded areas under the action of Schiff base to evaluate the effect of Schiff base on the corrosion rate of magnesium alloy. Figure 4 As shown, (a), (b), and (c) are the surface morphologies of the alloy after immersion in NaCl solution, Schiff base, and 3,4-2-hydroxybenzaldehyde for 24 hours to remove corrosion products; Figure 4 In (a), the sample surface after immersion in NaCl solution showed obvious localized corrosion, with a corrosion height difference of 57.126 μm and a pit depth of 85.462 μm. In contrast, no obvious localized corrosion was observed on the sample surface after adding Schiff base, with a corrosion height difference of only 24.596 μm and a pit depth of only 37.005 μm, which was significantly lower than that after NaCl solution. This indicates that Schiff base can effectively slow down the corrosion rate of magnesium alloy and inhibit localized corrosion. In addition, the corrosion of the sample immersed in 3,4-2-hydroxybenzaldehyde was more severe, with a corrosion height difference of 71.126 μm and a pit depth of 162.096 μm, which was significantly increased compared to NaCl solution. This indicates that 3,4-2-hydroxybenzaldehyde accelerated the corrosion rate and localized corrosion tendency of magnesium alloy.

[0061] Table 2 Comparison of IP, PF, and standard deviation of different corrosion inhibitor solutions

[0062]

[0063] Example 3

[0064] In Example 3, the semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors includes:

[0065] (1) Preparation of micropore parallel array test device: MB15 magnesium alloy sample and acrylic sheet are bonded together and connected and fixed with silicone sealing plate. The array of through holes on the acrylic sheet and the surface of magnesium alloy sample form an open cavity to accommodate corrosion inhibitor; wherein, the through holes form a 4×4 array.

[0066] (2) Prepare 0.05wt.% NaCl, 0.5wt.% NaCl and 5wt.% NaCl solutions as corrosion inhibitors, and use pure water as a control; in the through holes of the 4×4 array, every four holes are grouped together and the same corrosion inhibitor is injected;

[0067] (3) Inject a certain amount of the prepared corrosion inhibitor into each well, keep it in a constant humidity chamber for 24 hours, and after soaking, remove the corrosion inhibitor and dry the sample.

[0068] (4) Take a vertical photograph of the etched sample under side lighting conditions;

[0069] Figure 5 In the image, (a) shows the sample in the testing device after the corrosion reaction is complete; (b) shows the sample as captured by the image acquisition device. Figure 5 (b) shows that the RGB values ​​of the corrosion circle are 153:152:146, and the RGB value ratio is in the range of 1 to 1.3:1 to 1.2:1. The average brightness and brightness standard deviation are used to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate and local corrosion of magnesium alloy. Figure 5 The analysis results of the corrosion area in (b) are shown in Table 3. It can be seen that after immersion in 0.05 wt% NaCl solution for 24 hours, the IP, PF, standard deviation, and average brightness of MB15 alloy did not change significantly compared with pure water, indicating that its corrosion behavior was similar. After immersion in 0.5 wt% NaCl solution for 24 hours, the standard deviation and PF of the corrosion area were slightly higher than those of pure water and 0.05 wt% NaCl, but the average brightness increased, indicating that the corrosion rate of the alloy was significantly increased, and the tendency for local corrosion was slightly enhanced. After immersion in 5 wt% NaCl solution for 24 hours, the IP, PF, standard deviation, and average brightness of the corrosion area all increased significantly, indicating that the corrosion rate of the alloy was significantly accelerated and severe local corrosion occurred. Compared with the corrosion behavior of ZE21B magnesium alloy, the corrosion performance of MB15 alloy in 0.05 wt% NaCl and 0.5 wt% NaCl solutions was relatively uniform, and no obvious local corrosion was observed. However, in 5 wt% NaCl solution, the surface of MB15 alloy showed significant uneven corrosion.

[0070] Table 3 Comparison of IP, PF, standard deviation, and average brightness of NaCl solutions with different concentrations

[0071]

[0072] The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors disclosed in this invention can simultaneously measure corrosion inhibitors on a large scale, avoiding large-scale experimental trial and error and significantly improving efficiency. It can initially select corrosion inhibitors that can effectively slow down the corrosion rate of magnesium alloys or significantly inhibit localized corrosion behavior, enriching and improving the magnesium alloy corrosion inhibitor database. Parallel measurements of corrosion inhibitors at different locations on the same magnesium alloy surface can avoid measurement system errors caused by differences in magnesium alloy samples. Vertical photography under side lighting conditions can simultaneously measure the corrosion rate and localized corrosion degree of magnesium alloys. Adding the assessment of the corrosion inhibitor's ability to inhibit localized corrosion during the screening and evaluation of magnesium alloy corrosion inhibitors will help to more comprehensively evaluate the effect of corrosion inhibitors.

[0073] The technical solutions and technical details disclosed in the embodiments of this invention are merely illustrative of the inventive concept of this invention and do not constitute a limitation on the technical solutions of the embodiments of this invention. Any conventional changes, substitutions, or combinations made to the technical details disclosed in the embodiments of this invention have the same inventive concept as this invention and are within the protection scope of the claims of this invention.

Claims

1. A semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, characterized in that, The methods include: An array of small holes is formed on the surface of a magnesium alloy, the small holes having open cavities to accommodate corrosion inhibitors; Different corrosion inhibitors were injected into the array of small holes; The corrosion inhibitor injected into the small hole reacts with the magnesium alloy under set conditions; After the corrosion reaction was completed, the magnesium alloy surface was photographed vertically under side lighting conditions to obtain an image containing the corrosion area in the array of pinholes. The eroded areas in the obtained image are identified to obtain image information for each eroded area in the array of pinholes; the image information includes the maximum brightness, minimum brightness, average brightness, brightness standard deviation, and area percentage of the eroded area at different brightness levels; The corrosion effect is evaluated based on the image information of the corroded area; corrosion For products with an RGB value ratio within the range of 1~1.3:1~1.2:1, the inhibitory effect of the corrosion inhibitor on the corrosion rate and localized corrosion degree of magnesium alloy is evaluated using the average brightness and brightness standard deviation. For corrosion products with an RGB value ratio outside the range of 1~1.3:1~1.2:1, the inhibitors that can inhibit localized corrosion of magnesium alloy are first screened based on the brightness standard deviation. Then, the height difference between the corroded interface and the uncorroded interface is observed using a laser confocal microscope to evaluate the inhibitory effect of the corrosion inhibitor on the corrosion rate. The corrosion inhibition capacity and corrosion factor are calculated using image information. The calculation formula is as follows: ； ； Where IP represents corrosion inhibition capability, PF represents corrosion factor, and L represents corrosion resistance. a For average brightness, L M For maximum brightness, L m This is the minimum brightness.

2. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors according to claim 1, characterized in that, The corrosion reaction is carried out on a testing device, which includes a magnesium alloy and a transparent polymer plate fixedly connected to the surface of the magnesium alloy. The transparent polymer plate has an array of through holes. The magnesium alloy surface and the through holes form an open cavity to accommodate the corrosion inhibitor.

3. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors according to claim 2, characterized in that, The transparent polymer sheet is an acrylic sheet.

4. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors according to claim 1, characterized in that, ImageJ is used to identify the black-and-white contrast of an image in order to obtain image information.

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