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

Abstract

The semi-quantitative high-throughput evaluation method of the magnesium alloy corrosion inhibitor disclosed by the embodiment of the invention comprises the following steps: forming small holes which are arranged in an array and are provided with open type accommodating cavities for accommodating the corrosion inhibitor on the surface of magnesium alloy; different corrosion inhibitors are injected into the small holes arranged in the array; the corrosion inhibitor and the magnesium alloy are subjected to corrosion reaction under set conditions; after the reaction is finished, carrying out vertical photographing on the surface of the magnesium alloy under the condition of side light irradiation to obtain an image containing a corrosion area in the small hole; identifying 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 be used for measuring scale-magnitude corrosion inhibitors at the same time, large-scale experiment trial and error are avoided, and the efficiency is improved; the corrosion inhibitor is measured in parallel at different positions on the same magnesium alloy surface, so that system errors caused by different magnesium alloy samples can be avoided; the corrosion rate and the local corrosion degree of the magnesium alloy can be measured at the same time by adopting vertical photographing under the condition of side light irradiation.

Description

Technical Field

[0001] The invention belongs to the technical field of metal corrosion protection, and in particular relates to a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors. Background Art

[0002] Magnesium and magnesium alloys have unique advantages in the fields of lightweight structural materials and biodegradable medical metal materials. However, the potential difference between the second phase, impurities and the magnesium matrix in magnesium alloys will aggravate the local corrosion of magnesium alloys, resulting in a decrease in its corrosion resistance. This problem greatly limits the widespread application of magnesium and magnesium alloys. Corrosion inhibitors are an effective anti-corrosion method. 2+ Inorganic substances that form insoluble complexes or react to form dense corrosion products can effectively reduce the corrosion rate of magnesium alloys, or be adsorbed on the surface of the magnesium matrix to isolate the matrix from the corrosive medium, and selectively adsorb on certain second phase surfaces to weaken the galvanic corrosion tendency of magnesium alloys, thereby slowing down the corrosion process of the metal.

[0003] Many magnesium alloy corrosion inhibitors have been reported so far, but most studies mainly focus on the effect of corrosion inhibitors on the corrosion rate of magnesium alloys, and fail to fully evaluate magnesium alloy corrosion inhibitors in combination with the actual service needs of magnesium alloys; the screening of corrosion inhibitors mainly relies on large-scale trial and error experiments, which is inefficient; traditional experimental methods such as corrosion weight loss, hydrogen evolution, and electrochemical testing are mainly used, which have high resource consumption, low test efficiency, and a small screening range.

[0004] For magnesium alloys, whether as structural lightweight materials or degradable medical metal materials, they need to maintain sufficient mechanical strength during service to bear the corresponding loads. However, during long-term service in a corrosive environment, as corrosion occurs, the mechanical bearing capacity of magnesium alloys will also decrease. Studies have found that there is no direct correspondence between the change in the mechanical properties of magnesium alloys and the speed of corrosion rate, while the mechanical integrity of magnesium alloys is directly related to the degree of local corrosion. The potential difference between the second phase, impurities and the magnesium matrix in magnesium alloys causes severe local corrosion of magnesium alloys. Under stress conditions, the microcracks formed around the corrosion pits lead to local stress concentration, which becomes the source of crack development, causing the mechanical properties of magnesium alloys to significantly decrease and fail prematurely during service. Therefore, it is inaccurate to evaluate the effect of magnesium alloy corrosion inhibitors only by the speed of corrosion rate, and the mechanical integrity of magnesium alloys under the action of corrosion inhibitors should be considered as an important indicator for the screening and evaluation of corrosion inhibitors. However, there is currently no method to evaluate the local corrosion behavior of magnesium alloys under the action of corrosion inhibitors to achieve a comprehensive and integrated evaluation of magnesium alloy corrosion inhibitors. Summary of the invention

[0005] In view of this, the technical solution disclosed in some embodiments is a semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, comprising:

[0006] An array of small holes is formed on the surface of the magnesium alloy, wherein the small holes have an open cavity for accommodating the corrosion inhibitor;

[0007] Inject different corrosion inhibitors into the small holes arranged in an array;

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

[0009] After the corrosion reaction is finished, the surface of the magnesium alloy is photographed vertically under the condition of side light illumination to obtain an image containing the corrosion area in the array holes;

[0010] Identify the corrosion area in the acquired image and obtain image information of each corrosion area in the array holes;

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

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

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

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

[0015] The semi-quantitative high-throughput evaluation method of magnesium alloy corrosion inhibitor disclosed in some embodiments also includes calculating the corrosion inhibition ability and corrosion factor using image information, and the calculation formula is:

[0016]

[0017] Among them, IP is the corrosion inhibition capacity, PF is the corrosion factor, L a is the average brightness, L M is the maximum brightness, L m is the minimum brightness.

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

[0019] In some embodiments of the semi-quantitative high-throughput evaluation method of magnesium alloy corrosion inhibitors, 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 of magnesium alloy corrosion inhibitors disclosed in the embodiment of the present invention can simultaneously measure corrosion inhibitors of large scale, avoid large-scale experimental trial and error, significantly improve efficiency, and preliminarily select corrosion inhibitors that can effectively slow down the corrosion rate of magnesium alloys or can significantly inhibit the local corrosion behavior of alloys, enriching and improving the database of magnesium alloy corrosion inhibitors; parallel measurement of corrosion inhibitors at different positions on the same magnesium alloy surface can avoid measurement system errors caused by different magnesium alloy samples; vertical photography under side light irradiation conditions can simultaneously measure the corrosion rate and local corrosion degree of magnesium alloys. Adding an evaluation of the ability of the corrosion inhibitor to inhibit local corrosion when screening and evaluating magnesium alloy corrosion inhibitors will help to more comprehensively evaluate the effect of the corrosion inhibitor. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0023] Figure 2 Semi-quantitative high-throughput evaluation experimental sample diagram of magnesium alloy corrosion inhibitor disclosed in Example 1;

[0024] Figure 3 Semi-quantitative high-throughput evaluation experimental sample diagram of magnesium alloy corrosion inhibitor disclosed in Example 2;

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

[0026] Figure 5 A sample diagram of the semi-quantitative high-throughput evaluation experiment of the magnesium alloy corrosion inhibitor disclosed in Example 3. DETAILED DESCRIPTION

[0027] The word "embodiment" used herein as an "exemplary" does not necessarily mean that any embodiment described is superior or better than other embodiments. Performance index tests in the embodiments of the present invention are performed using conventional test methods in the art unless otherwise specified. It should be understood that the terms described in the embodiments of the present invention are only used to describe specific implementation methods and are not intended to limit the contents disclosed in the embodiments of the present invention.

[0028] Unless otherwise specified, the technical and scientific terms used herein have the same meanings as commonly understood by ordinary technicians in the technical field to which the embodiments of the present invention belong; other experimental methods and technical means not specifically specified in the embodiments of the present invention refer to experimental methods and technical means commonly used by ordinary technicians in the field.

[0029] The terms "substantially" and "approximately" used herein are used to describe small fluctuations. For example, they can refer to 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%. The numerical data represented or presented in the range format herein are used only for convenience and brevity, and should therefore be flexibly interpreted as including not only the values ​​clearly listed as the limits of the range, but also all independent values ​​or sub-ranges contained in the range. For example, the numerical range of "1-5%" should be interpreted as including not only the clearly listed values ​​of 1% to 5%, but also the independent values ​​and sub-ranges within the range shown. Therefore, independent values ​​such as 2%, 3.5% and 4% and sub-ranges such as 1%-3%, 2%-4% and 3%-5% are included in this numerical range. This principle also applies to the range of only one numerical value. In addition, such an interpretation applies regardless of the width of the range or the characteristics described.

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

[0031] In order to better illustrate the present invention, numerous specific details are provided in the specific examples below. It should be understood by those skilled in the art that the present invention can be implemented without certain specific details. In the embodiments, some methods, means, instruments, equipment, etc. well known to those skilled in the art are not described in detail in order to highlight the gist of the present invention.

[0032] Under the premise of no conflict, the technical features disclosed in the embodiments of the present invention may be arbitrarily combined, and the resulting technical solutions belong to the contents disclosed in the embodiments of the present invention.

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

[0034] Small holes arranged in an array are formed on the surface of the magnesium alloy, and the small holes have an open cavity for accommodating the corrosion inhibitor; generally, the corrosion reaction between the surface of the magnesium alloy and the corrosion inhibitor can be carried out on a test device, and the test device includes a magnesium alloy and a transparent polymer plate fixedly connected to the surface of the magnesium alloy, and the transparent polymer plate is provided with through holes arranged in an array; the surface of the magnesium alloy and the through holes form an open cavity for accommodating the corrosion inhibitor; in some embodiments, the transparent polymer plate is an acrylic plate;

[0035] Inject different corrosion inhibitors into the small holes arranged in the array; usually, different corrosion inhibitors can be corrosive solutions of different types, concentrations and compositions, which can react with the magnesium alloy to produce corrosion;

[0036] The corrosion inhibitor injected into the small hole reacts with the magnesium alloy under set conditions; usually, 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, ambient atmosphere, etc.;

[0037] After the corrosion reaction is completed, the magnesium alloy surface is photographed vertically under the condition of side light illumination to obtain an image of the corrosion area in the array holes; usually, after the corrosion reaction is carried out under the set environmental conditions for a set time, the expected corrosion effect can be obtained, so as to meet the needs of subsequent photography analysis;

[0038] Generally, the corrosion products accumulated on the surface of magnesium alloy appear white under the refraction and diffuse reflection of light. The higher the corrosion rate of magnesium alloy, the thicker the corrosion products, and the more obvious the whiteness of the corrosion products under side light. Under the same lighting conditions, the uncorroded area appears black due to the lack of light reflection, and it can effectively avoid the misjudgment of the corrosion inhibition effect due to the reaction of some corrosion inhibitors with magnesium alloys to form a dark precipitation protective layer. When magnesium alloys are locally corroded, corrosion products will accumulate around the corrosion sites. Therefore, the photos taken vertically under side light can directly reflect the effect of corrosion inhibitors on the local corrosion behavior of magnesium alloys.

[0039] Identify the corrosion area in the obtained image and obtain the image information of each corrosion area in the array holes; generally, the image is processed by using an image processing method, for example, the black and white contrast of the image can be identified by using ImageJ to obtain the image information; usually, the image information includes the maximum brightness, minimum brightness, average brightness, brightness standard deviation, and area proportion of the corrosion area at different brightness levels;

[0040] The image information can be used to further calculate the corrosion inhibition capacity and corrosion factor. The calculation formula is:

[0041]

[0042] Among them, IP is the corrosion inhibition capacity, PF is the corrosion factor, L a is the average brightness, L M is the maximum brightness, and Lm is the minimum brightness. Generally, the larger the IP value, the faster the corrosion rate of the alloy in the solution, and the larger the PF value, the more serious the local corrosion of the alloy.

[0043] The corrosion effect is evaluated based on the image information of the corrosion area. Generally, the corrosion effect evaluation method is determined based on the RGB numerical ratio characteristics of the corrosion product in the corrosion area; if the RGB numerical ratio is within 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 rate and local corrosion degree of the magnesium alloy; if the RGB numerical ratio of the corrosion product is not within the range of 1 to 1.3:1 to 1.2:1, the corrosion inhibitor that can inhibit the local corrosion of the magnesium alloy is first screened according to the brightness standard deviation, and 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 rate; the technical details are further illustrated in conjunction with the embodiments below.

[0044] Example 1

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

[0046] (1) Preparation of a micropore parallel array test device: a ZE21B magnesium alloy sample and an acrylic plate are laminated together and connected and fixed with a silicone sealing plate, and an open cavity for accommodating the corrosion inhibitor is formed between the arrayed through holes on the acrylic plate and the surface of the magnesium alloy sample; wherein the through holes form a 3×4 array;

[0047] (2) 0.05wt.% NaCl, 0.5wt.% NaCl and 5wt.% NaCl solutions were prepared as corrosion inhibitors, and pure water was used as a control; in the through-holes of the 3×4 array, every three holes were used as a group and the same corrosion inhibitor was injected;

[0048] (3) Inject a certain amount of slow-release agent into each through-hole and keep it in a constant humidity chamber for 24 hours. After the immersion is completed, the corrosion inhibitor is sucked out and the sample is dried;

[0049] (4) Take a vertical photo of the corroded sample under side light illumination;

[0050] Figure 2 In the figure, (a) is the sample in the test device after the corrosion reaction is completed; (b) is the sample photographed by the image acquisition device; Figure 2As shown in (b), the RGB of 0.5wt.% NaCl is 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 on the corrosion rate and local corrosion of magnesium alloys; 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 and IP as well as the 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 with different concentrations

[0052]

[0053] In Example 1, the average brightness and standard deviation are used to evaluate the inhibitory effect of the corrosion rate and local corrosion degree of the magnesium alloy. The average brightness reflects the overall brightness in the corrosion area. A higher brightness value means that the white color of the corrosion area is more obvious, indicating that the corrosion rate of the magnesium alloy is accelerated; while the brightness standard deviation reflects the uniformity of the brightness in the corrosion area. The larger the standard deviation, the more serious the local corrosion phenomenon. Compared with pure water and NaCl solution, the average brightness and standard deviation are smaller than those of NaCl solution, indicating that the solution has an inhibitory effect on the corrosion rate and local corrosion of the magnesium alloy. The closer the average brightness and standard deviation are to pure water, the better the corrosion inhibitor effect.

[0054] Example 2

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

[0056] (1) Preparation of a micropore parallel array test device: a ZE21B magnesium alloy sample and an acrylic plate are laminated together and connected and fixed with a silicone sealing plate, and an open cavity for accommodating the corrosion inhibitor is formed between the arrayed through holes on the acrylic plate and the surface of the magnesium alloy sample; 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 respectively 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 a 3×3 array, every three holes were used as a group and the same corrosion inhibitor was injected;

[0058] (3) Inject a certain amount of corrosion inhibitor into each well and keep it in a constant humidity chamber for 24 hours. After the immersion is completed, the corrosion inhibitor is sucked out and the sample is dried;

[0059] (4) Take a vertical photo of the corroded sample under side light illumination;

[0060] Figure 3 In the figure, (a) is the sample in the test device after the corrosion reaction is completed; (b) is the sample photographed by the image acquisition device; Figure 3 As shown in (b), the RGB of 3,4-2-hydroxybenzaldehyde is 192:172:128, and the RGB value ratio is not in the range of 1-1.3:1-1.2:1; ImageJ is first used to analyze the standard deviation and PF of the corrosion circle in the image. As shown in Table 2, compared with the NaCl solution, the standard deviation and PF of the Schiff base are significantly reduced, indicating that the Schiff base can significantly inhibit the local corrosion of the magnesium alloy, and the IP value of the Schiff base is lower than that of the NaCl solution, indicating that the Schiff base can effectively slow down the corrosion rate of the magnesium alloy; then a laser confocal microscope is used to verify the height difference between the corroded area and the uncorroded area under the action of the Schiff base to evaluate the effect of the Schiff base on the corrosion rate of the magnesium alloy, as shown in Table 2. Figure 4 As shown in (a), (b), and (c) are the surface morphologies of the alloy after the corrosion products are removed after being immersed in NaCl solution, Schiff base, and 3,4-2-hydroxybenzaldehyde for 24 hours; Figure 4 In (a), obvious local corrosion occurred on the surface of the sample after immersion in NaCl solution, and its corrosion height difference and pitting pit depth were 57.126μm and 85.462μm, respectively. In contrast, no obvious local corrosion was observed on the surface of the sample after adding Schiff base, and its corrosion height difference and pitting pit depth were only 24.596μm and 37.005μm, which were significantly lower than those in NaCl solution. This shows that Schiff base can effectively slow down the corrosion rate of magnesium alloy and inhibit local corrosion. In addition, the corrosion of the sample immersed in 3,4-2-hydroxybenzaldehyde was more serious, and its corrosion height difference and pitting pit depth were 71.126μm and 162.096μm, respectively. Compared with NaCl solution, the pitting pit depth increased significantly, indicating that 3,4-2-hydroxybenzaldehyde accelerated the corrosion rate and local 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 of magnesium alloy corrosion inhibitor includes:

[0065] (1) Preparation of a micropore parallel array test device: a MB15 magnesium alloy sample and an acrylic plate are laminated together and connected and fixed with a silicone sealing plate, and an open cavity for accommodating the corrosion inhibitor is formed between the arrayed through holes on the acrylic plate and the surface of the magnesium alloy sample; wherein the through holes form a 4×4 array;

[0066] (2) 0.05wt.% NaCl, 0.5wt.% NaCl and 5wt.% NaCl solutions were prepared as corrosion inhibitors, and pure water was used as a control; in the through-holes of the 4×4 array, every four holes were used as a group and the same corrosion inhibitor was injected;

[0067] (3) Inject a certain amount of corrosion inhibitor into each well and keep it in a constant humidity chamber for 24 hours. After the immersion is completed, the corrosion inhibitor is sucked out and the sample is dried;

[0068] (4) Take a vertical photo of the corroded sample under side light illumination;

[0069] Figure 5 In the figure, (a) is the sample in the test device after the corrosion reaction is completed; (b) is the sample photographed by the image acquisition device; Figure 5 As shown in (b), the RGB of the corrosion circle is 153:152:146, and the RGB value ratio is in the range of 1-1.3:1-1.2:1. The average brightness and brightness standard deviation are used to evaluate the inhibitory effect 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 0.05wt% NaCl solution for 24 hours, the IP, PF, standard deviation and average brightness of the MB15 alloy did not change significantly compared with pure water, indicating that their corrosion behaviors were similar; after immersion in 0.5wt% NaCl solution for 24 hours, the standard deviation and PF of the corrosion area were slightly higher than those of pure water and 0.05wt% NaCl, but the average brightness increased, indicating that the corrosion rate of the alloy was significantly improved, and the local corrosion tendency was slightly enhanced; after immersion in 5wt% NaCl solution for 24 hours, the IP, PF, standard deviation and average brightness of the corrosion area 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 0.05wt% NaCl and 0.5wt% NaCl solutions was relatively uniform, and no obvious local corrosion occurred; however, in 5wt% 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 of magnesium alloy corrosion inhibitors disclosed in the embodiment of the present invention can simultaneously measure corrosion inhibitors of large scale, avoid large-scale experimental trial and error, significantly improve efficiency, and preliminarily select corrosion inhibitors that can effectively slow down the corrosion rate of magnesium alloys or can significantly inhibit the local corrosion behavior of alloys, enriching and improving the database of magnesium alloy corrosion inhibitors; parallel measurement of corrosion inhibitors at different positions on the same magnesium alloy surface can avoid measurement system errors caused by different magnesium alloy samples; vertical photography under side light irradiation conditions can simultaneously measure the corrosion rate and local corrosion degree of magnesium alloys. Adding an evaluation of the ability of the corrosion inhibitor to inhibit local corrosion when screening and evaluating magnesium alloy corrosion inhibitors will help to more comprehensively evaluate the effect of the corrosion inhibitor.

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

Claims

1. A semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitors, characterized in that: Methods include: Forming small holes arranged in an array on the surface of the magnesium alloy, wherein the small holes have an open cavity for accommodating a corrosion inhibitor; Inject different corrosion inhibitors into the small holes arranged in an array; The corrosion inhibitor injected into the small hole reacts with the magnesium alloy under set conditions; After the corrosion reaction is finished, the surface of the magnesium alloy is photographed vertically under the condition of side light illumination to obtain an image containing the corrosion area in the array holes; Identify the corrosion area in the acquired image and obtain image information of each corrosion area in the array holes; The corrosion effect is evaluated based on the image information of the corrosion area.

2. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 1, characterized in that: The image information includes the maximum brightness, minimum brightness, average brightness, brightness standard deviation, and area ratio of the corrosion area at different brightness levels.

3. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 2, characterized in that: The RGB value ratio of the corrosion products was in the range of 1-1.3:1-1.2:1, and the average brightness and brightness standard deviation were used to evaluate the inhibitory effect on the corrosion rate and local corrosion degree of magnesium alloy.

4. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 2, characterized in that: The RGB value ratio of the corrosion product is not in the range of 1-1.3:1-1.2:

1. Firstly, the corrosion inhibitor that can inhibit the local corrosion of magnesium alloy is screened according to the brightness standard deviation. 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.

5. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 2, characterized in that: It also includes the calculation of corrosion inhibition capacity and corrosion factor using image information, and the calculation formula is: Among them, IP is the corrosion inhibition capacity, PF is the corrosion factor, L a is the average brightness, L M is the maximum brightness, L m is the minimum brightness.

6. The semi-quantitative high-throughput evaluation method of magnesium alloy corrosion inhibitor according to claim 1, characterized in that: The corrosion reaction is carried out on a test device, which includes a magnesium alloy and a transparent polymer plate fixedly connected to the surface of the magnesium alloy, wherein the transparent polymer plate is provided with through holes arranged in an array; the magnesium alloy surface and the through holes form an open cavity for accommodating a corrosion inhibitor.

7. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 6, characterized in that: The transparent polymer sheet is an acrylic sheet.

8. The semi-quantitative high-throughput evaluation method for magnesium alloy corrosion inhibitor according to claim 1, characterized in that: ImageJ was used to identify the black and white contrast of the image to obtain image information.

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