Acoustic emission test platform for multiple corrosion of metal in complex ammonia environment and use method of acoustic emission test platform

Abstract

The invention provides an acoustic emission test platform for multiple corrosion of metal in a complex ammonia environment and a use method of the acoustic emission test platform. The acoustic emission test platform comprises a corrosion medium configuration system, a reaction system, an electrochemical test system and an acoustic emission test system. The corrosive medium configuration system is used for accurately controlling the input of liquid ammonia, impurity gas and solution through a valve and a flow meter; the reaction system adopts constant-temperature water bath heating and magnetic stirring and is integrated with a temperature-pressure integrated sensor; the electrochemical testing system realizes corrosion promotion and monitoring through a three-electrode structure; the acoustic emission testing system captures corrosion signals in real time through a magnetic force fixing sensor. The sample bracket supports a multi-sample parallel contrast test, and can simulate a horizontal or vertical corrosion scene of a bottom plate and a wall surface of the storage tank. The method can realize conjoint analysis of multiple corrosion mechanisms, provides data support for corrosion rate modeling and life prediction, and is suitable for detection of complex corrosion environments such as ammonia, hydrogen and carbon dioxide.

Description

Technical Field

[0001] The present invention relates to the technical field of corrosion performance testing devices, in particular to an acoustic emission testing platform for metal multiple corrosion in a complex ammonia environment and a method for using the platform. Background Art

[0002] Liquid ammonia is a colorless liquid with a strong pungent odor. It is produced by pressurizing or cooling gaseous ammonia and has a boiling point of -33.5°C. As an important chemical raw material, liquid ammonia is widely used in fertilizer production, refrigerants, pharmaceuticals, and pesticides. In the defense industry, it is a component of rocket propellant. Its high nitrogen content (82.3%) makes it a highly effective direct fertilizer, significantly increasing agricultural yields. Liquid ammonia is highly corrosive, volatile, and toxic, requiring strict storage in pressure-resistant cylinders or tank trucks. Corrosion problems during storage and transportation of liquid ammonia primarily manifest as corrosion of the tank floor and welds, particularly on carbon steel or low-alloy steel. Corrosion of the bottom of liquid ammonia tanks primarily involves electrochemical corrosion and stress corrosion. Electrochemical corrosion primarily occurs when electrolytes such as chlorides and sulfides in the water deposited on the tank floor react with the metal, leading to localized thinning or perforation. Stress corrosion occurs when impurities such as oxygen and carbon dioxide mixed with residual welding stresses in the liquid ammonia react to induce crack propagation, particularly in the weld area. Corrosion can cause the bottom plate to thin or perforate, leading to liquid ammonia leaks, environmental pollution, personal poisoning, and even fires or explosions. Localized corrosion or stress corrosion cracking can spread, weakening the tank's pressure-bearing capacity and causing structural failure. Traditional corrosion detection methods, such as ultrasonic testing and electrochemical testing, suffer from technical bottlenecks such as insufficient sensitivity, inability to monitor dynamic processes in real time, and difficulty distinguishing corrosion mechanisms. Summary of the Invention

[0003] In view of this, the purpose of the present invention is to provide a metal multi-corrosion acoustic emission testing platform in a complex ammonia environment and its use method, to achieve joint analysis of multiple corrosion mechanisms, provide data support for corrosion rate modeling and life prediction, and is suitable for detection in complex corrosion environments such as ammonia, hydrogen and carbon dioxide.

[0004] To achieve the above objectives, the present invention adopts the following technical solutions: an acoustic emission testing platform for metal multi-corrosion in a complex ammonia environment, comprising: a corrosive medium configuration system, a reaction system, an electrochemical testing system, and an acoustic emission testing system; The corrosive medium configuration system includes a liquid ammonia storage device 18, an impurity gas storage device, an impurity ion solution storage tank 2, a compressor 14, a first peristaltic pump 13, a gas flow meter 15, and a liquid flow meter 12; and is used to detect the input flow of liquid ammonia, impurity gas, and impurity ion solution; the impurity gas includes oxygen, carbon dioxide, and nitrogen; The reaction system includes a reactor 7, a constant temperature water bath device 6, a permanent magnet DC motor 26, an electric stirrer 28, a clamp 33, a second peristaltic pump 21, an exhaust gas recovery bottle 20 and a temperature and pressure integrated sensor. The outer wall of the reactor 7 is provided with an acoustic emission sensor 8; The electrochemical testing system includes a working electrode 23, a reference electrode 22, an auxiliary electrode 24 and an electrochemical workstation 25. The working electrode 23, the reference electrode 22 and the auxiliary electrode 24 are connected to the outside through the bottom of the reactor 7; The acoustic emission test system includes an acoustic emission sensor 8, a preamplifier 9, an acquisition card 10, and a data display and processing device 11. The acoustic emission sensor 8 is connected to the preamplifier 9, the preamplifier 9 is connected to the acquisition card 10, the acquisition card 10 is connected to the data display and processing device 11, and the data display and processing device 11 is also connected to the electrochemical workstation 25.

[0005] In a preferred embodiment, the reactor 7 is provided with a reactor liquid inlet 29 and a reactor gas inlet 30; the liquid ammonia storage device 18 and the impurity gas storage device are connected to the gas flow meter 15 through the compressor 14, and the gas flow meter 15 is connected to the reactor gas inlet 30; the impurity ion solution storage tank 2 is connected to the liquid flow meter 12 through the first peristaltic pump 13, and the liquid flow meter 12 is connected to the reactor liquid inlet 29; the waste gas recovery bottle 20 is connected to the reactor 7.

[0006] In a preferred embodiment, the impurity gas storage device includes an oxygen storage device 191 , a carbon dioxide storage device 192 , and a nitrogen storage device 193 .

[0007] In a preferred embodiment, a jacket 37 is provided on the outside of the reactor 7, and the inside of the jacket 37 is connected to a constant temperature water bath device 6 via a second peristaltic pump 21. The constant temperature water bath device 6 outputs hot water to the inside of the jacket 37 to control the internal temperature of the reactor 7.

[0008] In a preferred embodiment, a clamp 33 is provided inside the reactor 7, and a working electrode external terminal 34, an auxiliary electrode external terminal 35 and a reference electrode external terminal 32 are provided outside the reactor 7, which are respectively connected to the working electrode 23, the auxiliary electrode 24 and the reference electrode 22; the working electrode 23 is placed on the clamp 33 and then connected to the working electrode external terminal 34.

[0009] In a preferred embodiment, the electrochemical workstation 25 and the working electrode external terminal 34, the auxiliary electrode external terminal 35 and the reference electrode external terminal 32 are connected by wires; the electrochemical workstation 25 reads the potential of the working electrode 23 relative to the reference electrode 22 during the corrosion process, and observes the changes in potential and current on the data display and processing device 11.

[0010] In a preferred embodiment, after the acoustic emission sensor 8 collects the acoustic emission signal, it is amplified and filtered by the preamplifier 9 and then enters the acquisition card 10 to convert it into data. The acquisition card 10 observes the signal changes in real time through the data display and processing device 11, and processes and analyzes the signal data after the acquisition is completed.

[0011] In a preferred embodiment, the reactor 7 is provided with a reactor cover 38, and the rotating shaft of the electric stirrer 28 passes through the reactor cover 38 and extends into the interior of the reactor 7. The top of the electric stirrer 28 is connected to a permanent magnet DC motor 26, and the electric stirrer 28 is used to uniformly mix the corrosive medium in the reactor 7; the interior of the reactor 7 is symmetrically provided with a first temperature-pressure integrated sensor 31 and a second temperature-pressure integrated sensor 36 for simultaneously detecting temperature and pressure.

[0012] In a preferred embodiment, the clamp 33 includes a first sample fixing end 39 and a second sample fixing end 41, and a slot 40 is formed between the first sample fixing end 39 and the second sample fixing end 41, and the slot 40 is used to place the metal sample; the second sample fixing end 41 is connected to a rotating handle 42; by rotating the handle 42, the second sample fixing end 41 is moved to fix the metal sample in the slot 40 between the first sample fixing end 39 and the second sample fixing end 41; the clamp 33 is also connected to a support column 43, and the bottom of the support column 43 is connected to the external terminal 34 of the working electrode.

[0013] The present invention also provides a method for using an acoustic emission test platform for metal multiple corrosion in a complex ammonia environment, which uses the above-mentioned acoustic emission test platform for metal multiple corrosion in a complex ammonia environment; first, open the lid 38 of the reactor 7, install the metal sample on the fixture 33, connect the electrochemical workstation 25 and the working electrode external terminal 34, the auxiliary electrode external terminal 35 and the reference electrode external terminal 32 with wires; close the lid 38 to seal the reactor 7, and adjust the liquid ammonia storage tank outlet valve 16, the impurity ion solution storage tank outlet valve 1, the reactor gas outlet valve 23, and the auxiliary electrode external terminal 34 according to the experimental requirements. The body inlet valve 3 and the reactor liquid inlet valve 4 are opened or closed, and the first peristaltic pump 13 and the compressor 14 are opened or closed to control the liquid ammonia, impurity gas, and impurity ions to enter the reactor 7. During the introduction, the electric stirrer 28 is turned on to mix the corrosive solution evenly; at the same time, the constant temperature water bath device 6 is operated to make the corrosive environment medium reach the required temperature; the acoustic emission sensor 8 is coated with a coupling agent and fixed around the outer wall of the reactor 7; the acoustic emission sensor 8 collects the acoustic emission signal, and the electrochemical workstation 25 senses the potential and current changes, and finally displays and processes them through the data display and processing device 11.

[0014] Compared with existing technologies, this invention offers the following advantages: By simulating a corrosive environment in the laboratory and analyzing acoustic emission signal characteristics, it reveals the acoustic emission patterns underlying corrosion initiation and propagation, providing a theoretical basis for on-site equipment corrosion monitoring. It also provides data support for evaluating the severity of corrosion-active defects, aiding in decision-making regarding maintenance opportunities. Furthermore, it can verify the sensitivity and reliability of acoustic emission equipment, confirming the sensor's ability to capture weak corrosion signals, and guiding on-site sensor selection and placement. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the overall structure of a preferred embodiment of the present invention; Figure 2 This is a schematic diagram of the connection between the reactor and other structures in a preferred embodiment of the present invention; Figure 3 A schematic structural diagram of a clamp according to a preferred embodiment of the present invention; Figure 4 This is a schematic diagram of the use state of the clamp according to the preferred embodiment of the present invention; Figure 5 A schematic diagram of the metal sample according to a preferred embodiment of the present invention; Figure 6 This is a distribution diagram of the acoustic emission sensors along the outer wall of the reactor in a preferred embodiment of the present invention; The accompanying drawings are marked as follows: impurity ion solution storage tank outlet valve 1, impurity ion solution storage tank 2, reactor gas inlet valve 3, reactor liquid inlet valve 4, reactor exhaust gas outlet valve 5, constant temperature water bath device 6, reactor 7, acoustic emission sensor 8, preamplifier 9, acquisition card 10, data display and processing device 11, liquid flow meter 12, first peristaltic pump 13, compressor 14, gas flow meter 15, liquid ammonia storage tank outlet valve 16, oxygen storage tank outlet valve 171, carbon dioxide storage tank outlet valve 172, nitrogen storage tank outlet valve 173, liquid ammonia storage device 18, oxygen storage device 191, carbon dioxide storage device 192, nitrogen storage device 193 , waste gas recovery bottle 20, second peristaltic pump 21, reference electrode 22, working electrode 23, auxiliary electrode 24, electrochemical workstation 25, permanent magnet DC motor 26, reactor waste gas outlet 27, electric stirrer 28, reactor liquid inlet 29, reactor gas inlet 30, first temperature and pressure integrated sensor 31, reference electrode external terminal 32, clamp 33, working electrode external terminal 34, auxiliary electrode external terminal 35, second temperature and pressure integrated sensor 36, jacket 37, reactor cover 38, first sample fixing end 39, slot 40, second sample fixing end 41, rotating handle 42, support column 43, fixing screw 44, weld area 45. DETAILED DESCRIPTION

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0018] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0019] A kind of acoustic emission test platform for metal corrosion in complex ammonia environment, Figure 1-6 , including: corrosive medium configuration system, reaction system, electrochemical test system and acoustic emission test system; The corrosive medium configuration system includes a liquid ammonia storage device 18, an impurity gas storage device, an impurity ion solution storage tank 2, a compressor 14, a first peristaltic pump 13, a liquid flow meter 12 and a gas flow meter 15; the impurity gases include oxygen, carbon dioxide and nitrogen; the impurity gas storage device includes an oxygen storage device 191, a carbon dioxide storage device 192 and a nitrogen storage device 193.

[0020] The reaction system includes a reactor 7, a constant temperature water bath device 6, a permanent magnet DC motor 26, an electric stirrer 28, a fixture 33, a second peristaltic pump 21 and a temperature and pressure integrated sensor. The outer wall of the reactor 7 is provided with an acoustic emission sensor 8; The electrochemical test system includes a working electrode 23, a reference electrode 22, an auxiliary electrode 24 and an electrochemical workstation 25. The working electrode 23, the reference electrode 22 and the auxiliary electrode 24 are connected to the outside through a conductive device at the bottom of the reactor 7. The electrochemical workstation adopts a CHI604E model. The acoustic emission test system includes an acoustic emission sensor 8, a preamplifier 9, an acquisition card 10, and a data display and processing device 11. The acoustic emission sensor 8 is connected to the preamplifier 9, the preamplifier 9 is connected to the acquisition card 10, the acquisition card 10 is connected to the data display and processing device 11, and the data display and processing device 11 is also connected to the electrochemical workstation 25.

[0021] refer to Figure 1 and Figure 2After the reactor 7 is sealed, the liquid ammonia storage tank outlet valve 16 and the compressor 14 are opened to output ammonia gas. At the same time, the impurity gas storage tank outlet valves, which include the oxygen storage tank outlet valve 171, the carbon dioxide storage tank outlet valve 172, and the nitrogen storage tank outlet valve 173, are closed. The reactor gas inlet valve 3 is opened to allow ammonia gas to enter the reactor 7. After the ammonia gas is output, the liquid ammonia storage tank outlet valve 16 is closed. If it is necessary to add impurity gas to the reactor 7, taking oxygen as an example, the oxygen storage tank outlet valve 171 should be opened, and the carbon dioxide storage tank outlet valve 172 and the nitrogen storage tank outlet valve 173 should be closed at the same time to input oxygen into the reactor. The gas flow rate is displayed by the gas flow meter 15. Then, the oxygen storage tank outlet valve 171 should be closed, and so on. If impurity ions need to be added to the reactor, the impurity ion solution storage tank outlet valve 1 and the first peristaltic pump 13 should be opened to output the impurity ion solution. The impurity ion solution is prepared and stored in the impurity ion solution storage tank 2. The flow rate of the impurity ion solution is displayed by the liquid flow meter 12. The impurity solution is introduced by opening the reactor liquid inlet valve 4. After the reaction is completed, the waste gas should be discharged by closing the reactor gas inlet valve 3 and the reactor liquid inlet valve 4, and opening the reactor waste gas outlet valve 5. The waste gas enters the waste gas recovery bottle 20. The reactor 7 is provided with a jacket 37 on the outside. The interior of the jacket 37 is connected to the second peristaltic pump 21 and is connected to a constant temperature water bath 6. The constant temperature water bath 6 outputs hot water to the interior of the jacket 37 to control the internal temperature of the reactor 7.

[0022] The reactor 7 is provided with a fixture 33 inside, and the outside of the reactor 7 is provided with a working electrode external terminal 34, an auxiliary electrode external terminal 35, and a reference electrode external terminal 32, which are detachably connected to the working electrode 23, the auxiliary electrode 24, and the reference electrode 22, respectively. The working electrode 23 is placed on the fixture 33 and then connected to the working electrode external terminal 34. After the working electrode external terminal 34, the auxiliary electrode external terminal 35, and the reference electrode external terminal 32 are connected to the working electrode 23, the auxiliary electrode 24, and the reference electrode 22, respectively, the entire test platform can support electrochemically promoted corrosion or simple immersion corrosion testing.

[0023] Wires connect the electrochemical workstation 25 to the working electrode's external terminal 34, the auxiliary electrode's external terminal 35, and the reference electrode's external terminal 32. The working electrode 23 and the auxiliary electrode 24 form the anode and cathode, accelerating the corrosion of the working electrode 23. The electrochemical workstation 25 reads the potential of the working electrode 23 relative to the reference electrode 22 during the corrosion process, and the changes in potential and current are observed on the data display and processing device 11. Electrochemical testing and acoustic emission testing are performed simultaneously. After the corrosion experiment, the electrochemical and acoustic emission data are comprehensively processed and analyzed.

[0024] After the acoustic emission sensor 8 collects the acoustic emission signal, it is amplified and filtered by the preamplifier 9 and then enters the acquisition card 10 to convert it into data. The acquisition card 10 observes the signal changes in real time through the data display and processing device 11, and processes and analyzes the signal data after the acquisition is completed.

[0025] The reactor 7 is provided with a reactor cover 38. The rotating shaft of the electric stirrer 28 passes through the reactor cover 38 and extends deep into the interior of the reactor 7. The top of the electric stirrer 28 is connected to a permanent magnet DC motor 26. The permanent magnet DC motor 26 has the characteristics of low-speed force amplification and low noise, which is particularly suitable for acoustic emission detection tests. The electric stirrer 28 is used to evenly mix the corrosive medium in the reactor 7. The interior of the reactor 7 is symmetrically provided with a first integrated temperature and pressure sensor 31 and a second integrated temperature and pressure sensor 36 for simultaneous temperature and pressure detection. The first integrated temperature and pressure sensor 31 and the second integrated temperature and pressure sensor 36 integrate temperature and pressure detection functions. The temperature and pressure data are derived from the same location and are used to establish a corrosion rate model in combination with acoustic emission parameters. The reactor wall of the reactor 7 is made of a magnetic, heat-resistant and pressure-resistant magnetic metal material. The interior of the reactor wall is coated with a layer of liquid ammonia corrosion-resistant material. The exterior surface of the reactor wall is smooth, which facilitates the acoustic emission sensor 8 to be firmly fixed around the outer wall of the reactor, improving coupling and reducing sound wave attenuation.

[0026] refer to Figure 3 The fixture 33 includes a first sample fixing end 39 and a second sample fixing end 41, and a slot 40 is formed between the first sample fixing end 39 and the second sample fixing end 41, and the slot 40 is used to place the metal sample; the second sample fixing end 41 is connected to a rotating handle 42; by rotating the handle 42, the second sample fixing end 41 is moved to fix the metal sample in the slot 40 between the first sample fixing end 39 and the second sample fixing end 41; the fixture 33 is also connected to a support column 43, and the bottom of the support column 43 is connected to the external terminal 34 of the working electrode. Specifically, the bottom of the support column is mounted on the bottom of the kettle with a fixing screw 44, and the support column is connected to the external terminal 34 of the working electrode. The fixture 33 is a copper-plated titanium alloy structure that supports the simultaneous installation of multiple metal samples, including metal sheets, stress corrosion samples and welding samples, and the samples can be placed horizontally or vertically to simulate different corrosion scenarios such as the tank bottom plate and the tank container wall. Figure 5 For several metal specimens, including rectangular metal sheets, U-shaped metal sheets and U-shaped metal sheets in the weld area 45. Among them, the rectangular metal sheets are mounted horizontally or vertically on the fixture, such as Figure 4 shown.

[0027] A method for using an acoustic emission test platform for metal multiple corrosion in a complex ammonia environment, using the aforementioned acoustic emission test platform for metal multiple corrosion in a complex ammonia environment; first, opening the lid 38 of the reactor 7, installing a metal sample on the fixture 33, connecting the electrochemical workstation 25 and the working electrode external terminal 34, the auxiliary electrode external terminal 35, and the reference electrode external terminal 32 with wires; closing the lid 38 to seal the reactor 7, and adjusting the liquid ammonia storage tank outlet valve 16, the impurity gas storage tank outlet valve, the impurity ion solution storage tank outlet valve 1, and the reactor gas inlet valve according to experimental requirements. 3 and the reactor liquid inlet valve 4, open or close the first peristaltic pump 13 and the compressor 14 to control the entry of liquid ammonia, impurity gas, and impurity ions into the reactor 7. During the introduction, the electric stirrer 28 is turned on to mix the corrosive solution evenly. At the same time, the constant temperature water bath device 6 is operated to make the corrosive environment medium reach the required temperature. After the acoustic emission sensor 8 is coated with a coupling agent, it is fixed around the outer wall of the reactor 7 by a magnetic device. The acoustic emission sensor 8 collects the acoustic emission signal, and the electrochemical workstation 25 senses the potential and current changes, and finally displays and processes them through the data display and processing device 11.

[0028] The above is only an implementation case of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred implementation case as above, it is not used to limit the present invention. Any technician familiar with this profession can make certain changes or modifications to the structure and technical content disclosed above without departing from the scope of the technical solution of the present invention to become an equivalent implementation case with equivalent changes.

[0029] For example, the present invention is not limited to the corrosion environment being an ammonia environment, and is also applicable to corrosion experiments in environments such as hydrogen and carbon dioxide.

[0030] However, any simple modifications, equivalent changes and modifications made to the above implementation cases based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

[0031] The same meaning as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0032] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application; as used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form, and it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

Claims

1. A metal multi-corrosion acoustic emission testing platform in a complex ammonia environment, characterized by: include: Corrosive medium configuration system, reaction system, electrochemical test system and acoustic emission test system; The corrosive medium configuration system includes a liquid ammonia storage device (18), an impurity gas storage device, an impurity ion solution storage tank (2), a compressor (14), a first peristaltic pump (13), a gas flow meter (15), and a liquid flow meter (12); and is used to detect the input flow of liquid ammonia, impurity gas, and impurity ion solution; the impurity gas includes oxygen, carbon dioxide, and nitrogen; The reaction system comprises a reaction kettle (7), a constant temperature water bath device (6), a permanent magnet DC motor (26), an electric stirrer (28), a clamp (33), a second peristaltic pump (21), an exhaust gas recovery bottle (20) and a temperature-pressure integrated sensor, wherein an acoustic emission sensor (8) is provided on the outer wall of the reaction kettle (7); The electrochemical testing system includes a working electrode (23), a reference electrode (22), an auxiliary electrode (24), and an electrochemical workstation (25), wherein the working electrode (23), the reference electrode (22), and the auxiliary electrode (24) are connected to the outside through the bottom of the reactor (7); The acoustic emission test system comprises an acoustic emission sensor (8), a preamplifier (9), an acquisition card (10), and a data display and processing device (11), wherein the acoustic emission sensor (8) is connected to the preamplifier (9), the preamplifier (9) is connected to the acquisition card (10), the acquisition card (10) is connected to the data display and processing device (11), and the data display and processing device (11) is further connected to an electrochemical workstation (25).

2. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The reactor (7) is provided with a reactor liquid inlet (29) and a reactor gas inlet (30); the liquid ammonia storage device (18) and the impurity gas storage device are connected to the gas flow meter (15) through the compressor (14), and the gas flow meter (15) is connected to the reactor gas inlet (30); the impurity ion solution storage tank (2) is connected to the liquid flow meter (12) through the first peristaltic pump (13), and the liquid flow meter (12) is connected to the reactor liquid inlet (29); the waste gas recovery bottle (20) is connected to the reactor (7).

3. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The impurity gas storage device includes an oxygen storage device (191), a carbon dioxide storage device (192) and a nitrogen storage device (193).

4. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The outside of the reactor (7) is provided with a jacket (37), and the inside of the jacket (37) is connected to a constant temperature water bath device (6) through a second peristaltic pump (21). The constant temperature water bath device (6) outputs hot water to the inside of the jacket (37) to control the internal temperature of the reactor (7).

5. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The reactor (7) is provided with a fixture (33) inside, and the reactor (7) is provided with a working electrode external terminal (34), an auxiliary electrode external terminal (35) and a reference electrode external terminal (32) outside, which are connected to the working electrode (23), the auxiliary electrode (24) and the reference electrode (22) respectively; the working electrode (23) is placed on the fixture (33) and then connected to the working electrode external terminal (34).

6. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 5 is characterized in that: The electrochemical workstation (25) and the working electrode external terminal (34), the auxiliary electrode external terminal (35) and the reference electrode external terminal (32) are connected by wires; the electrochemical workstation (25) reads the potential of the working electrode (23) relative to the reference electrode (22) during the corrosion process, and observes the changes in potential and current on the data display and processing device (11).

7. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: After the acoustic emission sensor (8) collects the acoustic emission signal, it is amplified and filtered by the preamplifier (9) and then enters the acquisition card (10) to be converted into data. The acquisition card (10) observes the signal changes in real time through the data display and processing device (11), and processes and analyzes the signal data after the acquisition is completed.

8. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The reactor (7) is provided with a reactor cover (38), and the rotating shaft of the electric stirrer (28) passes through the reactor cover (38) and penetrates into the interior of the reactor (7). The top of the electric stirrer (28) is connected to a permanent magnet DC motor (26). The electric stirrer (28) is used to uniformly mix the corrosive medium in the reactor (7); a first temperature-pressure integrated sensor (31) and a second temperature-pressure integrated sensor (36) are symmetrically provided inside the reactor (7) for simultaneously detecting temperature and pressure.

9. The acoustic emission testing platform for metal corrosion in a complex ammonia environment according to claim 1 is characterized in that: The clamp (33) includes a first sample fixing end (39) and a second sample fixing end (41), wherein a slot (40) is formed between the first sample fixing end (39) and the second sample fixing end (41), and the slot (40) is used to place the metal sample; the second sample fixing end (41) is connected to a rotating handle (42); by rotating the handle (42), the second sample fixing end (41) is moved to fix the metal sample in the slot (40) between the first sample fixing end (39) and the second sample fixing end (41); the clamp (33) is also connected to a support column (43), and the bottom of the support column (43) is connected to an external terminal (34) of the working electrode.

10. A method for using an acoustic emission testing platform for metal corrosion in a complex ammonia environment, characterized in that A metal multi-corrosion acoustic emission test platform in a complex ammonia environment as described in any one of claims 1 to 9 is used; first, the lid (38) of the reactor (7) is opened, a metal sample is mounted on a fixture (33), and an electrochemical workstation (25) is connected to the working electrode external terminal (34), the auxiliary electrode external terminal (35) and the reference electrode external terminal (32) with a wire; the lid (38) is closed to seal the reactor (7), and the outlet valve (16) of the liquid ammonia storage tank, the outlet valve of the impurity gas storage tank, the outlet valve (1) of the impurity ion solution storage tank, the gas inlet valve (3) of the reactor are adjusted according to the experimental requirements. ) and the reactor liquid inlet valve (4), open or close the first peristaltic pump (13) and the compressor (14) to control the liquid ammonia, impurity gas, and impurity ions to enter the reactor (7); during the introduction, open the electric stirrer (28) to mix the corrosion solution evenly; at the same time, operate the constant temperature water bath device (6) to make the corrosion environment medium reach the required temperature; after coating the acoustic emission sensor (8) with coupling agent, fix it around the outer wall of the reactor (7); the acoustic emission sensor (8) collects the acoustic emission signal, and the electrochemical workstation (25) senses the potential and current changes, and finally displays and processes them through the data display and processing device (11).

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