Device and method for monitoring thin liquid film stress corrosion in situ in real time

Abstract

The invention discloses an in-situ real-time monitoring thin liquid film stress corrosion device and method, the device mainly comprises a stress loading device, a thin liquid film environment simulation device, an electrochemical corrosion device and an in-situ characterization device, a to-be-monitored sample is installed on the stress loading device; the thin liquid film environment simulation device and the electrochemical corrosion device are matched to simulate the thin liquid film stress corrosion process of the sample, and the in-situ characterization device is used for monitoring the thin liquid film stress corrosion process of the sample in real time. The thin liquid film formed by the method is stable, the corrosion condition and corrosion product composition of the material surface can be monitored in situ in real time, and the result is accurate.

Description

Technical Field

[0001] This invention belongs to the field of atmospheric stress corrosion technology, specifically relating to an in-situ real-time monitoring device and method for thin liquid film stress corrosion. Background Technology

[0002] Changes in relative humidity and temperature in the atmosphere can create a thin liquid film on the material surface. At a certain thickness, this film can form a galvanic cell effect, leading to electrochemical corrosion. Thin-film electrochemical corrosion involves more oxygen or corrosive gases, differing significantly from common aqueous solution electrochemical corrosion. Thin-film stress corrosion is one of the main causes of metallic material failure in atmospheric environments, posing a serious threat to the structural integrity and safe operation of critical equipment and infrastructure. While metal corrosion in the natural atmosphere is relatively slow, actual environmental corrosion testing is extremely costly. Current research on atmospheric stress corrosion behavior of metallic materials primarily focuses on accelerated testing to simulate actual service conditions and ultimately guide the prediction of atmospheric stress corrosion life and effective protection against it.

[0003] The study of stress corrosion of metals in atmospheric environments has attracted considerable attention from scholars, leading to the development of a series of atmospheric stress corrosion testing devices and methods. For example, Chinese patent CN115541483A discloses a "Test Method for the Interaction of Marine Atmospheric Environment-Elastic Tensile Stress on Metallic Materials," which involves pre-applying elastic tensile stress to the material and then exposing it to a real marine atmosphere. The electrochemical and mechanical properties of the exposed specimens are then tested, allowing for the evaluation of the material's damage behavior in the marine atmosphere. However, this method separates the actual atmospheric environment from subsequent performance testing, introducing other influencing factors and making it impossible to obtain timely and accurate information about the material's damage patterns in the marine atmosphere. Another example is Chinese patent CN107490608B, which discloses a "Situ Measurement Device for Mechanical-Electrochemical Interaction in a Thin-Film Environment." This is a wet-air method simulating stress corrosion in a liquid film environment. This device combines mechanical and electrochemical devices to achieve in-situ measurement of the mechanical-electrochemical interaction, observing and precisely controlling the liquid film thickness using a telephoto microscope. Although this device solves the problem of asynchronous mechanical and electrochemical testing in environments with thin liquid films of varying thicknesses, in actual testing, the liquid film formed by the condensation of moisture on the material surface is uneven and easily becomes dispersed droplets, leading to uneven electrochemical corrosion. Furthermore, since the material is loaded vertically, the droplets formed on the material surface are inevitably affected by gravity, and the droplets may slide downwards, making it difficult to form a stable thin liquid film. In addition, current thin liquid film electrochemical corrosion tests rely on post-test analysis of the corrosion morphology and corrosion products to infer the corrosion process and its patterns. However, inferring the entire corrosion process from the final products of thin liquid film corrosion is inherently uncertain.

[0004] Therefore, it is necessary to design a stress corrosion testing device for thin liquid film stability, and to realize in-situ real-time monitoring of the corrosion status and corrosion product composition of the material surface, which is extremely important for obtaining accurate stress corrosion law of thin liquid film. Summary of the Invention

[0005] The main objective of this invention is to provide a stress corrosion testing device that provides a stable thin liquid film and enables in-situ real-time monitoring of corrosion on the sample surface, thereby overcoming the shortcomings of the prior art.

[0006] To achieve the aforementioned objective, the technical solution adopted by this invention includes: an in-situ real-time monitoring device for thin liquid film stress corrosion, comprising:

[0007] A stress loading device includes a sample mounting fixture, on which the sample to be monitored is horizontally mounted;

[0008] A thin-film environment simulation device includes an electrolytic cell, a corrosion chamber, an atomizer, and a first heating device. The electrolytic cell contains a first electrolyte solution. A sample mounting fixture with a sample installed is placed on the electrolytic cell, and the sample is immersed in the first electrolyte solution, forming a thin liquid film between the liquid surface of the first electrolyte solution and the upper surface of the sample. The entire electrolytic cell is located within the corrosion chamber. The atomizer and first heating device includes a sealed cup, an atomizer, and a first heating device. The sealed cup contains a second electrolyte solution simulating a real environment. The atomizer is placed inside the sealed cup. The first heating device is located outside the sealed cup and is used to heat the second electrolyte solution inside the sealed cup. The sealed cup is connected to the corrosion chamber and is used to input the second electrolyte solution gas, atomized by the atomizer, into the corrosion chamber.

[0009] An electrochemical corrosion apparatus includes a reference electrode, a platinum electrode, and an electrochemical workstation. One end of the reference electrode and the platinum electrode are immersed in the first electrolytic solution, and the other end, together with the sample serving as the working electrode, is connected to the electrochemical workstation.

[0010] An in-situ characterization device, located above the sample, is used to monitor the stress corrosion process of the thin liquid film on the sample in real time.

[0011] In a preferred embodiment, the stress loading device further includes bolts, by which the specimen is horizontally fixed to the specimen mounting fixture.

[0012] In a preferred embodiment, the thin liquid film environment simulation device further includes a liquid film thickness measuring component for measuring the thickness of the thin liquid film formed on the sample, and / or the liquid film thickness measuring component includes a micrometer, a multimeter, and a platinum needle. The micrometer is located outside the corrosion chamber, and its lower end is connected to the upper end of the platinum needle. The lower end of the platinum needle extends into the corrosion chamber and is located above the sample. The two ends of the multimeter are respectively connected to the platinum needle and the sample.

[0013] In a preferred embodiment, the atomizing and first heating device further includes a temperature and humidity sensor, which is fixed to the sample mounting fixture.

[0014] In a preferred embodiment, the in-situ characterization device includes a laser Raman spectrometer, which is equipped with at least a Raman spectrometer for determining corrosion products generated during the stress corrosion process of a thin liquid film, as well as an optical microscope and a CCD camera for real-time acquisition of images of the sample surface.

[0015] In a preferred embodiment, the sealing cup and the corrosion chamber are connected by an air intake assembly, which includes an air intake duct and an air intake valve. The two ends of the air intake duct extend into the sealing cup and the corrosion chamber, respectively, and the air intake valve is disposed on the air intake duct.

[0016] In a preferred embodiment, the stress corrosion apparatus further includes an exhaust assembly connected to the corrosion chamber. The exhaust assembly includes an exhaust duct and an exhaust valve. The exhaust duct is connected to the corrosion chamber, and the exhaust valve is disposed on the exhaust duct.

[0017] In a preferred embodiment, the corrosion chamber further contains a corrosion solution and a second heating device for heating the corrosion solution.

[0018] In a preferred embodiment, the first electrolyte solution and the second electrolyte solution are identical.

[0019] On the other hand, the present invention also discloses another technical solution: a method for in-situ real-time monitoring of thin liquid film stress corrosion, comprising the following steps:

[0020] S1, The specimen is horizontally mounted on the specimen mounting fixture, and a specific deformation is applied to the specimen;

[0021] S2, Place the sample mounting fixture with the sample installed on the electrolytic cell, immerse the sample on it in the first electrolytic solution in the electrolytic cell, and at the same time put the entire electrolytic cell into the corrosion chamber containing pure water.

[0022] S3, immerse one end of the reference electrode and platinum electrode in the first electrolyte solution, and connect the other end together with the sample, which serves as the working electrode, to the electrochemical workstation;

[0023] S4, the atomizer is placed in a sealed cup containing the second electrolyte solution, and the first heating device located outside the sealed cup heats the second electrolyte solution. At the same time, the second electrolyte solution is atomized by the atomizer and input into the corrosion chamber, and the temperature and humidity in the corrosion chamber are adjusted.

[0024] S5, the in-situ characterization device is extended into the corrosion chamber and positioned above the sample to monitor the stress corrosion process of the thin liquid film on the sample in real time.

[0025] Compared with the prior art, the beneficial effects of the present invention are at least as follows:

[0026] 1. This invention selects to introduce stress in the horizontal direction to achieve in-situ real-time monitoring of thin liquid film stress corrosion. The test sample is placed horizontally, and the liquid film is not affected by gravity. In-situ testing is performed on the sample surface to observe the entire corrosion process of the sample and the changes in corrosion morphology and corrosion products on the material surface in real time. The results are accurate, solving the problem of introducing other interference factors by separately detecting the corrosion performance, corrosion morphology and corrosion products of the material's thin liquid film, and avoiding the problem of inaccurate corrosion law caused by inferring the entire corrosion process from the corrosion morphology and corrosion products of the final product.

[0027] 2. The liquid film thickness of the present invention is precisely controllable, the liquid film is stable and uniform as a whole, and the height difference between the electrolyte solution surface and the upper surface of the sample can be directly adjusted to form a liquid film of a specific thickness and stable uniformity. At the same time, controlling the temperature and humidity in the test environment can prevent the liquid film from evaporating and ensure long-term stability of the electrolyte concentration.

[0028] 3. This invention can simulate the liquid film properties of various real environments; the electrolyte solution in the sealed cup and electrolytic cell can be adjusted to obtain liquid films with different physicochemical properties, such as temperature, humidity, electrolyte concentration, pH value, saturated oxygen content, etc. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the structure of an in-situ real-time monitoring device for thin liquid film stress corrosion provided by the present invention;

[0031] Figure 2 This is a three-dimensional structural schematic diagram of the sample mounting fixture of the present invention;

[0032] Figure 3This is a schematic flowchart of an in-situ real-time monitoring method for thin liquid film stress corrosion provided by the present invention;

[0033] Figure label:

[0034] 1. Atomizer, 2. Sealed cup, 3. Corrosion chamber, 4. Electrolytic cell, 5. Inlet duct, 6. Inlet valve, 7. Exhaust duct, 8. Exhaust valve, 9. Temperature and humidity sensor, 10 / 11. Second heating device, 12. First heating device, 13. Micrometer, 14. Multimeter, 15. Platinum needle, 16. Sample mounting fixture, 161. Mounting part, 162. Fixing part, 163. Fixing hole, 17. Bolt, 18. Reference electrode, 19. Sample, 20. Platinum electrode, 21. In-situ characterization device, 211. CCD camera, 212. Raman spectrometer, 213. Optical microscope, 22. Electrochemical workstation. Detailed Implementation

[0035] The invention will be more fully understood through the following detailed description, which should be read in conjunction with the accompanying drawings. Detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the specific functional details disclosed herein should not be construed as limiting, but rather as the basis for the claims and as intended to teach those skilled in the art to employ the representative basis of the invention in different ways in any suitable detailed embodiment.

[0036] like Figure 1 As shown in the embodiment of the present invention, an in-situ real-time monitoring device for thin liquid film stress corrosion mainly includes a stress loading device, a thin liquid film environment simulation device, an electrochemical corrosion device, and an in-situ characterization device. The sample 19 to be monitored is installed on the stress loading device. The thin liquid film environment simulation device and the electrochemical corrosion device work together to simulate the stress corrosion process of the thin liquid film of the sample. The in-situ characterization device 21 is used to monitor the stress corrosion process of the thin liquid film of the sample 19 in real time.

[0037] In this embodiment, the stress loading device specifically includes a sample mounting clamp 16 and bolts 17. The sample 19 to be monitored is horizontally fixed to the sample mounting clamp 16 by the bolts 17. Unlike existing samples where the sample 19 is loaded vertically, this invention preferably designs the sample 19 to be loaded horizontally. This avoids the problem that droplets formed on the surface of the sample 19 due to moisture are affected by gravity, and the droplets may slide downwards, making it difficult to form a stable thin liquid film. Specifically, combined with Figure 2As shown, the sample mounting fixture 16 of the present invention includes a mounting part 161 and two fixing parts 162 extending downward from the left and right sides of the bottom of the mounting part 161. Each fixing part 162 has a horizontally penetrating fixing hole 163 at its bottom end. The two fixing holes 163 are positioned opposite each other in the horizontal direction and are respectively used for fixing the left and right ends of the sample with bolts 17, thereby fixing the sample 19 horizontally on the sample mounting fixture 16. A specific deformation can be applied to the sample 19 to be tested by adjusting the bolts 17.

[0038] In this embodiment, the thin liquid film environment simulation device specifically includes an electrolytic cell 4, an corrosion chamber 3, an atomizing and first heating device, and a liquid film thickness measuring component. The electrolytic cell 4 is located entirely within the corrosion chamber 3, which contains a first electrolytic solution. During testing, the sample mounting fixture 16 containing the sample 19 is mounted on the electrolytic cell 4 via its mounting part 161. The sample 19, which is horizontally fixed on the fixing part 162, is immersed in the first electrolytic solution. A thin liquid film is formed between the liquid surface of the first electrolytic solution and the upper surface of the sample. By adjusting the liquid level of the first electrolytic solution, a thin liquid film of a certain thickness can be formed on the upper surface of the sample 19.

[0039] The corrosion chamber 3 contains a corrosive solution. In this embodiment, the corrosive solution is pure water, used to heat the first electrolytic solution in the electrolytic cell 4 (i.e., water bath heating). The corrosion chamber 3 is also equipped with second heating devices 10 and 11 for heating the corrosive solution. Furthermore, in this embodiment, the top cover of the corrosion chamber 3 has holes to facilitate observation by the in-situ characterization device.

[0040] Preferably, the sample mounting clamp 16 and bolt 17 immersed in the first electrolyte solution are protected with insulating varnish. Similarly, the sample 19 is only reserved in a test area of ​​a certain size on the upper surface, and the rest of the position is protected with insulating varnish.

[0041] The atomizing and first heating device specifically includes a sealed cup 2, an atomizer 1, and a first heating device 12. The sealed cup 2 contains a second electrolyte solution identical to that in the electrolytic cell. The atomizer 1 is placed inside the sealed cup 2, and the first heating device 12 is located outside the sealed cup 2, specifically at the bottom of the sealed cup 2, for heating the second electrolyte solution inside the sealed cup 2. The sealed cup 2 is connected to the corrosion chamber 3, for introducing the atomized second electrolyte solution gas into the corrosion chamber 3. The atomizer 1 and the first heating device 12 can generate moisture with stable temperature and humidity, ensuring a constant temperature during the stress corrosion process of the material, while controlling the relative humidity reduces the evaporation of the electrolyte solution, thus making the thin liquid film thickness precisely controllable and uniformly stable.

[0042] In this embodiment, the sealed cup 2 and the corrosion chamber 3 are specifically connected by an air intake assembly, which includes an air intake duct 5 and an air intake valve 6. The two ends of the air intake duct 5 extend into the sealed cup 2 and the corrosion chamber 3, respectively, and the air intake valve 6 is mounted on the air intake duct 5. Additionally, the corrosion chamber 3 is connected to an exhaust assembly, which includes an exhaust duct 7 and an exhaust valve 8. The exhaust duct 7 is connected to the corrosion chamber 3, and the exhaust valve 8 is mounted on the exhaust duct 7. During testing, by opening the atomizer 1 and the first heating devices 10 and 11, and controlling the size of the air intake valve 6 and the exhaust valve 8, gases with corresponding temperature and humidity are generated to control the evaporation of the solution in the electrolytic cell 4, thereby stabilizing the physicochemical properties of the liquid film during the corrosion process. Furthermore, the atomizer and the first heating device also include a temperature and humidity sensor 9, which is fixed to the sample mounting fixture 16. This sensor is used to monitor the temperature and humidity in the simulated environment in real time and works in conjunction with the atomizer 1 and the first heating device 12 to control the temperature and humidity in the simulated environment.

[0043] A liquid film thickness measuring component is used to measure the thickness of the thin liquid film formed on the sample 19. In this embodiment, the liquid film thickness measuring component specifically includes a micrometer 13, a multimeter 14, and a platinum needle 15. The micrometer 13 is located outside the corrosion chamber 3, and its lower end is connected to the upper end of the platinum needle 15. The lower end of the platinum needle 15 extends into the corrosion chamber 3 and is located above the sample 19. The two ends of the multimeter 14 are connected to the platinum needle 15 and the sample 19, respectively. During testing, the actual liquid film thickness is measured using the micrometer 13, the multimeter 14, and the platinum needle 15. The liquid level in the electrolytic cell 4 is controlled using a dropper (not shown) to accurately achieve liquid films of different thicknesses. At the same time, the temperature and humidity are maintained for slow evaporation through the atomizer 1, the inlet valve 6, the exhaust valve 8, the first heating device 12, the second heating devices 10 and 11, and the temperature and humidity sensor 9, so that the liquid film thickness remains stable over a long period of time.

[0044] Preferably, the first electrolyte solution in the electrolytic cell 4 and the second electrolyte solution in the sealed cup 2 can be the same or different. By adding different electrolyte solutions to the sealed cup 2 and the electrolytic cell 4, thin liquid film environments of different corrosive media can be simulated.

[0045] In this embodiment, the electrochemical corrosion device specifically includes a reference electrode 18, a platinum electrode 20, and an electrochemical workstation 22. One end of both the reference electrode 18 and the platinum electrode 20 is immersed in the first electrolytic solution, while the other end, together with the sample 19 serving as the working electrode, is connected to the electrochemical workstation 22. In practice, the reference electrode 18 can be a saturated calomel electrode.

[0046] In this embodiment, the in-situ characterization device 21 passes through the cover plate of the corrosion chamber 3 and its bottom end is located above the sample 19. It is used to monitor the stress corrosion process of the thin liquid film of the sample in real time. It includes a laser Raman spectrometer, which is equipped with at least a Raman spectrometer 212 for determining the corrosion products generated during the stress corrosion process of the thin liquid film, an optical microscope 213, and a CCD camera 211 for real-time acquisition of images of the sample surface. Throughout the entire test process, the morphology and corrosion products of the sample 19 surface can be observed in real time through the Raman spectrometer 212 and the CCD camera 211 in the in-situ characterization device 21, obtaining dynamic, one-to-one mechanical-electrochemical-corrosion morphology and product test information. The horizontally loaded sample 19, with the help of the in-situ characterization device 21, can solve the problem of introducing other interference factors by separately detecting the thin liquid film corrosion performance, corrosion morphology, and corrosion products of the sample 19, and avoid the problem of inaccurate corrosion law caused by inferring the entire corrosion process from the final corrosion morphology and corrosion products. In addition, in-situ real-time monitoring of the corrosion morphology of the material surface under the thin liquid film and the corrosion mechanism of the corrosion products on the entire corrosion process of the material can be studied in depth, which has broad application prospects for guiding the protection of materials against thin liquid film corrosion.

[0047] like Figure 3 As shown, this invention also discloses another technical solution: a method for in-situ real-time monitoring of thin liquid film stress corrosion, comprising the following steps:

[0048] S1, mount the specimen 19 horizontally on the specimen mounting fixture 16, and rotate the bolt 17 to apply a specific deformation.

[0049] S2, the sample mounting fixture 16 with the sample 19 installed is placed on the electrolytic cell 4, and the sample 19 on it is immersed in the first electrolytic solution in the electrolytic cell 4. At the same time, the entire electrolytic cell 4 is placed into the corrosion chamber 3 containing pure water.

[0050] S3, immerse one end of the reference electrode 18 and the platinum electrode 20 into the first electrolytic solution, and connect the other end together with the sample 19, which serves as the working electrode, to the electrochemical workstation 22.

[0051] S4, place the atomizer 1 in the sealed cup 2 containing the second electrolyte solution, and the first heating device 12 located outside the sealed cup 2 heats the second electrolyte solution. At the same time, the second electrolyte solution is atomized by the atomizer 1 and input into the corrosion chamber 3, and the temperature and humidity in the corrosion chamber 3 are adjusted.

[0052] S5, the in-situ characterization device 21 is inserted into the corrosion chamber 3 and positioned above the sample 19 to monitor the stress corrosion process of the thin liquid film of the sample in real time.

[0053] It should be noted that the above steps are not limited in order. In a specific embodiment, the sample 19 to be monitored is horizontally fixed to the sample mounting fixture 16 by bolts 17. The sample mounting fixture 16 with sample 19 installed is placed on the electrolytic cell 4, and the temperature and humidity sensor 9 is fixed on the sample mounting fixture 16. The reference electrode 18 and platinum electrode 20 are placed in the solution in the electrolytic cell 4 and connected to the electrochemical workstation 22 together with sample 19. The electrolytic cell 4 with the electrodes installed is placed in the corrosion chamber 3 with the second heating device. The micrometer 13 and platinum needle 15 are installed on the outside of the corrosion chamber 3, and the platinum needle 15 is passed through the corrosion chamber cover and close to the liquid surface in the electrolytic cell 4. At the same time, the two ends of the multimeter 14 are connected to the platinum needle 15 and sample 19 by means of wires. The lens of the in-situ characterization device 21 passes through the gap in the center of the corrosion chamber 3 cover and the sample mounting fixture 16. All components in the electrolytic cell 4 except for the platinum needle 15, reference electrode 18, platinum electrode 20 and the gauge length of sample 19 are insulated with insulating varnish. The gas atomizer 1 is placed in a sealed cup 2 containing an electrolyte solution simulating a real environment. The base is the first heating device 12. The air inlet pipe 5 and the air inlet valve 6 are installed between the sealed cup 2 and the corrosion chamber 3. At the same time, the exhaust pipe 7 and the exhaust valve 8 are installed at the other end of the corrosion chamber 3.

[0054] During testing, a scale is drawn on the test surface of the working electrode, and the actual degree of deformation is measured with the help of the in-situ characterization device 21. The thickness of the liquid film is determined and controlled by recording the change in current of the multimeter 14 caused by the micrometer 13 and platinum needle 15 on the upper surface of the working electrode. The atomizer 1 and the first heating device 12 are turned on, and the size of the air inlet valve 6 and the air outlet valve 8 are controlled to generate gas with corresponding temperature and humidity to ensure that the solution in the electrolytic cell 4 does not evaporate and that the solution concentration and liquid film thickness remain stable.

[0055] Furthermore, the testing process involves observing the surface corrosion of the sample 19 in real time using the in-situ characterization device 21, and determining the corrosion products based on the Raman spectrum, thereby obtaining accurate stress-thin liquid film corrosion data and determining the variation law of the entire corrosion process.

[0056] The present invention provides an in-situ real-time monitoring device and method for thin-film stress corrosion, which has the following advantages: 1. The present invention selects horizontal stress to achieve in-situ real-time monitoring of thin-film stress corrosion. The test sample is placed horizontally, and the liquid film is not affected by gravity. Furthermore, in-situ testing is performed on the sample surface, allowing real-time observation of the entire corrosion process and changes in the corrosion morphology and corrosion products on the material surface. The results are accurate, solving the problem of introducing other interfering factors by separately detecting the corrosion performance, corrosion morphology, and corrosion products of the thin-film corrosion, and avoiding the problem of inaccurate corrosion patterns caused by inferring the entire corrosion process from the final corrosion morphology and corrosion products. 2. The liquid film thickness of the present invention is precisely controllable, and the liquid film is stable and uniform overall. The height difference between the electrolyte solution level and the upper surface of the sample can be directly adjusted to form a liquid film of a specific thickness and stable uniformity. Simultaneously, controlling the temperature and humidity in the test environment ensures that the liquid film does not volatilize and the electrolyte concentration remains stable over a long period. 3. The present invention can simulate the liquid film properties of various real environments. Different physicochemical properties of the liquid film can be obtained by adjusting the electrolyte solution in the sealed cup and electrolytic cell, such as temperature, humidity, electrolyte concentration, pH value, and saturated oxygen content.

[0057] All aspects, embodiments, features, and examples of this invention are to be regarded as illustrative in all respects and are not intended to limit the invention, the scope of which is defined only by the claims. Other embodiments, modifications, and uses will become apparent to those skilled in the art without departing from the spirit and scope of the invention as claimed.

[0058] The use of headings and sections in this invention is not intended to limit the invention; each section can be applied to any aspect, embodiment or feature of the invention.

Claims

1. An in-situ real-time monitoring device for thin liquid film stress corrosion, characterized in that: The device includes: A stress loading device includes a sample mounting fixture, on which the sample to be monitored is horizontally mounted; A thin-film environment simulation device includes an electrolytic cell, a corrosion chamber, an atomizer, and a first heating device. The electrolytic cell contains a first electrolyte solution. A sample mounting fixture with a sample installed is placed on the electrolytic cell, and the sample is immersed in the first electrolyte solution, forming a thin liquid film between the liquid surface of the first electrolyte solution and the upper surface of the sample. The entire electrolytic cell is located within the corrosion chamber. The atomizer and first heating device includes a sealed cup, an atomizer, and a first heating device. The sealed cup contains a second electrolyte solution simulating a real environment. The atomizer is placed inside the sealed cup. The first heating device is located outside the sealed cup and is used to heat the second electrolyte solution inside the sealed cup. The sealed cup is connected to the corrosion chamber and is used to input the second electrolyte solution gas, atomized by the atomizer, into the corrosion chamber. An electrochemical corrosion apparatus includes a reference electrode, a platinum electrode, and an electrochemical workstation. One end of the reference electrode and the platinum electrode are immersed in the first electrolytic solution, and the other end, together with the sample serving as the working electrode, is connected to the electrochemical workstation. An in-situ characterization device, located above the sample, is used to monitor the stress corrosion process of the thin liquid film on the sample in real time.

2. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The stress loading device also includes bolts, and the specimen is horizontally fixed to the specimen mounting fixture by the bolts.

3. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The thin liquid film environment simulation device further includes a liquid film thickness measuring component for measuring the thickness of the thin liquid film formed on the sample, and / or the liquid film thickness measuring component includes a micrometer, a multimeter and a platinum needle. The micrometer is located outside the corrosion chamber and its lower end is connected to the upper end of the platinum needle. The lower end of the platinum needle extends into the corrosion chamber and is located above the sample. The two ends of the multimeter are connected to the platinum needle and the sample, respectively.

4. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The atomizing and first heating device also includes a temperature and humidity sensor, which is fixed on the sample mounting fixture.

5. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The in-situ characterization device includes a laser Raman spectrometer, which is equipped with at least a Raman spectrometer for determining the corrosion products generated during the stress corrosion process of a thin liquid film, as well as an optical microscope and a CCD camera for real-time acquisition of images of the sample surface.

6. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The sealing cup and the corrosion chamber are connected by an air intake assembly, which includes an air intake duct and an air intake valve. The two ends of the air intake duct extend into the sealing cup and the corrosion chamber, respectively, and the air intake valve is disposed on the air intake duct.

7. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The stress corrosion apparatus also includes an exhaust assembly connected to the corrosion chamber. The exhaust assembly includes an exhaust duct and an exhaust valve. The exhaust duct is connected to the corrosion chamber, and the exhaust valve is disposed on the exhaust duct.

8. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The corrosion chamber also contains a corrosion solution and a second heating device for heating the corrosion solution.

9. The in-situ real-time monitoring device for thin liquid film stress corrosion according to claim 1, characterized in that: The first electrolyte solution and the second electrolyte solution are exactly the same.

10. A method for in-situ real-time monitoring of thin liquid film stress corrosion, characterized in that: The method includes: S1, The specimen is horizontally mounted on the specimen mounting fixture, and a specific deformation is applied to the specimen; S2, Place the sample mounting fixture with the sample installed on the electrolytic cell, immerse the sample on it in the first electrolytic solution in the electrolytic cell, and at the same time put the entire electrolytic cell into the corrosion chamber containing pure water. S3, immerse one end of the reference electrode and platinum electrode in the first electrolyte solution, and connect the other end together with the sample, which serves as the working electrode, to the electrochemical workstation; S4, the atomizer is placed in a sealed cup containing the second electrolyte solution, and the first heating device located outside the sealed cup heats the second electrolyte solution. At the same time, the second electrolyte solution is atomized by the atomizer and input into the corrosion chamber, and the temperature and humidity in the corrosion chamber are adjusted. S5, the in-situ characterization device is extended into the corrosion chamber and positioned above the sample to monitor the stress corrosion process of the thin liquid film on the sample in real time.

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