In-situ monitoring device and method for corrosion and aging state of coating

Abstract

The invention belongs to the technical field of coating corrosion and aging monitoring, and particularly relates to an in-situ monitoring device and method for the corrosion and aging state of a coating material in a marine environment, and a main body structure comprises an online measurement and transmission module, and a power supply module, a computer terminal, a coating corrosion and aging monitoring probe and an environment monitoring probe which are respectively connected with the online measurement and transmission module, each coating corrosion and aging monitoring probe is provided with an environment monitoring probe, can be directly attached to the surface of a to-be-detected coating material or a coating structure to carry out online in-situ monitoring of coating impedance, directly reflects the aging state of the to-be-detected coating material or the coating structure, and can be repeatedly used; according to the coating corrosion and aging state in-situ monitoring method, the aging degree of a to-be-detected coating is judged in real time according to impedance data monitored by the coating corrosion and aging state in-situ monitoring device, and the relation between the aging states of various coating systems under different environmental conditions and coating impedance is determined. And the relevance between the impedance of different types of coatings and the external environment and the aging state is established.

Description

Technical field:

[0001] The present invention belongs to the technical field of coating corrosion and aging monitoring, and specifically relates to an in-situ monitoring device and method for the corrosion and aging state of a coating material in a marine environment, which is used for in-situ, long-term, continuous measurement of the electrochemical properties of the coating material and remote data acquisition. Background technology:

[0002] The protection treatment of key equipment and infrastructure such as ships, offshore wind power, port bridges, etc. mainly adopts the method of physically isolating the metal substrate and the corrosive medium with anti-corrosion coating. Once the anti-corrosion coating fails, it will not only affect the appearance of the equipment / facility, but also affect the function and performance. Especially the marine atmospheric environment: various environmental stresses such as humidity, heat, ultraviolet rays, salt spray, pollutants, etc. have a great impact on the environmental adaptability of the anti-corrosion coating. The aging and corrosion problems of the anti-corrosion coating are more prominent, causing serious environmental pollution and safety accidents, causing immeasurable economic losses. Therefore, it is necessary to monitor the protective status of the anti-corrosion coating on marine equipment / facilities, and timely and accurately grasp the real-time change information of the anti-corrosion coating in the actual service environment, which is conducive to timely maintenance and treatment of the anti-corrosion coating and avoid accidents caused by corrosion failure.

[0003] The essence of marine environmental corrosion is the electrochemical corrosion process after water, salt, etc. in the atmosphere / seawater form a thin liquid film layer / large volume electrolyte on its surface, which conforms to the general law of electrochemistry. Based on this, the in-situ monitoring technology of electrochemical corrosion came into being. Among them, the electrochemical impedance test method is widely used for corrosion monitoring of metal or coating structures of equipment / facilities due to its fast measurement speed and small interference to the structure. The corrosion aging state of the coating is evaluated by the size of the low-frequency impedance value. For example, Chinese Patent 202211446054.1 discloses an in-situ online monitoring device for the aging state of an organic coating, including an electrode pair, a multi-channel impedance test unit, and a remote control unit connected to the multi-channel impedance test unit. The electrode pair is used to be embedded in the base metal of the coated metal part to be tested. The material of the electrode pair is the same as that of the base metal. One end of the electrode pair contacts the coating of the coated metal part to be tested, and the other end is connected to the multi-channel impedance test unit. The multi-channel impedance test unit collects the coating impedance data of the coated metal part to be tested and analyzes it to obtain the calculation result. The remote control unit evaluates the aging state of the coating of the coated metal part to be tested in the field according to the calculation result;

[0004] The monitoring method includes the following steps:

[0005] S1. Laboratory accelerated environmental test:

[0006] ⑴ Determine the environmental accelerated aging factors and environmental parameters of the on-site service environment of the coated metal parts to be tested;

[0007] (2) Use the same metal, coating and coating process as the coated metal parts to be tested to make a test plate with a coating on the surface of the metal plate;

[0008] ⑶ According to the environmental accelerated aging factor and environmental parameters, set the laboratory accelerated environmental test parameters according to 10 to 100 times the field environmental equivalent;

[0009] (4) Use an in-situ online monitoring device for the aging state of an organic coating to conduct laboratory accelerated environmental tests on the test panels. During the test, collect the coating impedance data of the test panels, analyze the change law of the impedance modulus of the coating from the initial state to the aging failure state, select the corresponding impedance equivalent circuit model, and establish a coating aging state grading evaluation standard in combination with the appearance change to determine the impedance modulus threshold when the coating fails;

[0010] S2. Use the in-situ online monitoring device for the aging status of organic coatings to conduct in-situ real-time monitoring of the coating service status of the coated metal parts to be tested:

[0011] (1) Setting the impedance equivalent circuit model and impedance modulus threshold determined in step S1 in the remote control unit;

[0012] (2) The multi-channel impedance test unit collects the coating impedance data of the coated metal parts to be tested and analyzes it in combination with the impedance equivalent circuit model to obtain the calculation result of the impedance modulus value;

[0013] ⑶ The remote control unit compares the calculated result with the set impedance modulus threshold to evaluate the aging status of the coating on the field service of the coated metal parts to be tested, and uploads the evaluation result to the client. If the evaluation result is close to the impedance modulus threshold or lower than the impedance modulus threshold, it will be warned or alarmed. The 0.1Hz impedance is used as the basis, and the impedance ≥10 9 Ω·cm 2 Excellent, 10 8 -10 9 Ω·cm 2 For good, 10 7 -10 8 Ω·cm 2 For general, 10 6 -10 7 Ω·cm 2 Poor, less than 10 6 Ω·cm 2Failure. Chinese patent 202010093889.8 discloses a device for in-situ monitoring of underwater anti-corrosion coatings of marine structures, comprising: a flange, a lower flange cabin sealed with the flange through a first connector, and a welding pad sealed with the lower flange cabin through a second connector. A reference electrode, a counter electrode, a first working electrode and a second working electrode are arranged on the upper surface of the flange, and the reference electrode, the counter electrode, the first working electrode and the second working electrode are arranged so that the upper surface is in the same plane as the upper surface of the flange; the reference electrode signal line passes through the lower flange cabin and enters the internal wiring of the marine structure to connect to the reference electrode end of the electrochemical workstation, the counter electrode signal line passes through the lower flange cabin and enters the internal wiring of the marine structure to connect to the counter electrode end of the electrochemical workstation, the first working electrode and the second working electrode are connected to a relay arranged in the lower flange cabin, and the relay is connected to the working electrode end of the electrochemical workstation through the internal wiring of the marine structure; when in use, the upper surfaces of the reference electrode, the counter electrode, the first working electrode and the second working electrode are in contact with the seawater environment;

[0014] The steps of the monitoring method include:

[0015] Circuit connection, the first working electrode and the second working electrode of the device are connected to the relay, the monitoring reference electrode is connected to the reference electrode end of the electrochemical workstation through a wire, the counter electrode is connected to the counter electrode end of the electrochemical workstation through a wire, and the common end of the relay is connected to the working electrode end of the electrochemical workstation through a wire;

[0016] Read the curve of coating impedance changing with frequency, and use the impedance-frequency scanning function of the electrochemical workstation to measure the curve of coating impedance changing with frequency for the first working electrode and the second working electrode;

[0017] Evaluation of coating damage rate: Read the low-frequency impedance modulus value of the working electrode coating at 0.1 Hz to calculate the coating damage rate.

[0018] The in-situ monitoring device for coating aging state in the prior art adopts the method of prefabricating working electrodes of the same material as the structure to be detected and coating the same coating, which has great limitations: on the one hand, if it is directly applied to the structure, it is necessary to pre-embed the electrode on the structure before painting, which is complicated to operate and difficult to maintain and replace in the later stage; on the other hand, if an external method is adopted, it is necessary to brush a layer of the same coating as the structure to be detected on the probe of the monitoring device, and it is difficult to ensure consistency in the two brushing processes, and the monitoring results cannot directly reflect the aging state of the structure. In addition, the use of low-frequency impedance to evaluate the aging state or degree of the coating makes the evaluation quantitative index too single, and the pertinence and applicability are unclear. The evaluation results deviate greatly from the actual aging state of the coating, because the coating impedance is closely related to factors such as the external environment (such as whether it is in the marine atmosphere or seawater environment, and the temperature and humidity of the atmospheric environment) and the type of coating. Therefore, a device and method for in-situ monitoring of the corrosion aging state of the coating is developed and designed to study the corrosion behavior and law of the coating in the marine atmosphere and seawater environment, and provide technical support for the early warning and maintenance of marine environmental corrosion of coated structures. Summary of the invention:

[0019] The purpose of the present invention is to overcome the shortcomings of the prior art, develop and design an in-situ monitoring device and method for the corrosion and aging state of a coating, judge the degree of coating aging in real time, and determine the relationship between the aging state and coating impedance of various coating systems under different environmental conditions.

[0020] In order to achieve the above-mentioned purpose, the main structure of the in-situ monitoring device for the coating corrosion and aging status involved in the present invention includes an online measurement and transmission module and a power supply module, a computer terminal, a coating corrosion and aging monitoring probe and an environmental monitoring probe respectively connected thereto, wherein the coating corrosion and aging monitoring probe is arranged on the coating to be tested, and the environmental monitoring probe is arranged near the coating corrosion and aging monitoring probe, and the two correspond one to one.

[0021] The main structure of the online measurement and transmission module of the present invention comprises a single-chip microcontroller and a timing clock, a communication interface circuit, a wireless transmission unit, a memory and a signal generator respectively connected thereto, wherein the communication interface circuit is connected to a computer terminal, the memory and the signal generator are mutually connected, the signal generator is connected to a coating corrosion aging monitoring probe through a conditioning and power amplifier circuit, and the coating corrosion aging monitoring probe is connected to the single-chip microcontroller through a filtering / compensation circuit and an A / D data collector to form a loop;

[0022] The power supply module includes a solar panel and a battery connected thereto;

[0023] The main structure of the coating corrosion and aging monitoring probe includes an outer shell and an inner core arranged inside the outer shell, wherein: an inert metal layer is arranged on the top of the outer shell, an ion conductive layer is arranged on the bottom, an electrolyte solution is arranged between the two, an insulating layer is arranged on the surface of the outer shell except the ion conductive layer, and a reference electrode is arranged in the electrolyte solution; an electrolyte solution is arranged inside the inner core, an ion conductive head is arranged on the bottom, an insulating layer is arranged on the surface of the inner core except the ion conductive head, an inert metal layer is arranged in the electrolyte solution, and an elastic telescopic part is arranged between the insulating layer and the ion conductive head; the inert metal layer and the reference electrode are respectively connected to conductive leads, and the conductive leads pass through the insulating layer.

[0024] The wireless transmission unit of the present invention is based on GSM mobile communication technology and adopts SMS or GPRS mode for encrypted remote data communication. It does not need to lay cables along the line, has greater openness and flexibility in equipment addition, upgrading and expansion, can greatly reduce construction costs, reduce measurement costs, and will not cause data loss even if the data is read at long intervals (4 measurements per day can store data for half a year).

[0025] The signal generator can output 4 excitation signals concurrently, supporting the synchronous measurement of 4 sets of coating corrosion and aging monitoring probes;

[0026] The ion conductive layer and the ion conductive head are both solid hydrophilic ion conductors;

[0027] The insulating layer is a transparent hydrophobic insulating layer;

[0028] The reference electrode is a solid reference electrode.

[0029] The coating corrosion aging state in-situ monitoring device of the present invention can remotely transmit and realize unattended atmospheric corrosion monitoring data acquisition in remote areas, thereby reducing the cost and difficulty of data acquisition. There is no need to separately prepare a working electrode made of the same material as the coating to be tested. The device is easy to use and can be applied to metal materials in different environments. It has wide applicability, does not consume materials, and can be reused.

[0030] When not in use, the root of the ion conductive head is retracted into the inner core to prevent leakage of the electrolyte solution, and the head of the ion conductive head exceeds the bottom surface of the outer shell;

[0031] When in use, the coating corrosion aging monitoring probe is directly fixed and attached to the surface of the coating to be tested, the ion conductive layer is closely attached to the surface of the coating to be tested, and the ion conductive head simultaneously contacts the surface of the coating to be tested and retracts into the inner core by a certain distance, ensuring that all ion conductive heads are in close contact with the coating to be tested;

[0032] During measurement, in a humid marine atmosphere, the micropores and other defects of the coating to be tested absorb moisture and electrolytes (this process is further aggravated as the coating ages), so that the inert metal layer in the outer shell, the reference electrode and the inert metal layer in the inner core in contact with it form a three-electrode system. A polarization potential is applied to scan in the positive or negative direction at a set speed to obtain a polarization curve. The slope of the curve is the DC impedance of the coating to be tested. The size of the DC impedance value represents the degree of aging of the coating to be tested (the larger the DC impedance value, the better the corrosion resistance of the coating to be tested). In this process, after the signal generator receives the instruction of the single-chip microcontroller, it simultaneously outputs 4 electrical signals, which are applied to several coating corrosion aging monitoring probes through conditioning and power amplifier circuits. The polarization potential and polarization generated by the coating to be tested The current and other data are sent to the A / D data acquisition device through the filtering / compensation circuit. The single-chip microcontroller processes several sets of polarization potential and polarization current data collected synchronously, stores them in the memory after analysis (directly calculates and converts them into DC impedance values), and transmits them back to the computer terminal through the wireless transmission unit. At the same time, the single-chip microcontroller outputs instructions to control the environmental monitoring probe to measure continuously in real time, and collects and stores the temperature, humidity, pressure and other measurement data of the environment in which the coating corrosion and aging monitoring probe bound to it is located. The single-chip microcontroller then associates the DC impedance of the coating to be tested with its surrounding environmental parameters to comprehensively evaluate the aging status of the coating. Among them, when the wireless transmission unit is turned on for a long time to collect data at the computer terminal, it can also read long-term data from the memory for transmission.

[0033] Compared with the prior art, the present invention is suitable for marine atmosphere or seawater environment, and can accurately judge the aging state of the coating to be tested based on DC impedance and external environment monitoring: the coating corrosion aging state in-situ monitoring device has a simple structure, each coating corrosion aging monitoring probe is equipped with an environmental monitoring probe, the two are close to each other in space, and the data are correlated with each other. The monitoring probe is easy to install and use, and has wide applicability. It can be directly attached to the surface of the coating material to be tested or the coated structure to perform online in-situ monitoring of the coating impedance, directly reflect the aging state of the coating material to be tested or the coated structure and can be reused. There is no need to prepare the coating corrosion aging monitoring probe with the same material as the coating to be tested, so the corrosion behavior and law of the coating in the marine atmosphere and seawater environment can be studied, and technical support can be provided for the early warning and maintenance of marine environmental corrosion of coated structures; the coating corrosion aging state in-situ monitoring method judges the aging degree of the coating to be tested in real time through the impedance data monitored by the coating corrosion aging state in-situ monitoring device, determines the relationship between the aging state and coating impedance of various coating systems under different environmental conditions, and establishes the correlation between the impedance of different types of coatings and the external environment and aging state. Description of the drawings:

[0034] Figure 1 It is a schematic diagram of the main structural principle of the present invention.

[0035] Figure 2 It is a structural schematic diagram of the online measurement and transmission module involved in the present invention.

[0036] Figure 3 It is a schematic transverse cross-sectional view of the housing involved in the present invention.

[0037] Figure 4 It is a longitudinal cross-sectional schematic diagram of the housing involved in the present invention.

[0038] Figure 5 It is a schematic longitudinal cross-sectional view of the inner core involved in the present invention. Specific implementation method:

[0039] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0040] Embodiment 1:

[0041] The main structure of the coating corrosion aging state in-situ monitoring device involved in this embodiment is as follows: Figure 1 As shown, it includes an online measurement and transmission module 1, a power supply module 2, a computer terminal 3, a coating to be tested 4, a coating corrosion and aging monitoring probe 5 and an environmental monitoring probe 6; the online measurement and transmission module 1 is respectively connected to the power supply module 2 and the computer terminal 3, as well as a plurality of coating corrosion and aging monitoring probes 5 arranged on the coating to be tested 4 and environmental monitoring probes 6 corresponding one to one with the coating corrosion and aging monitoring probes 5.

[0042] The main structure of the online measurement and transmission module 1 involved in this embodiment is as follows Figure 2 As shown, it includes a single-chip microcontroller 11, a timing clock 12, a communication interface circuit 13, a wireless transmission unit 14, a memory 15, a signal generator 16, a conditioning and power amplifier circuit 17, a filtering / compensation circuit 18 and an A / D data collector 19; the single-chip microcontroller 11 is connected to the environmental monitoring probe 6, the timing clock 12, the communication interface circuit 13, the wireless transmission unit 14, the memory 15 and the signal generator 16 respectively, the signal generator 16 is connected to the coating corrosion aging monitoring probe 5 through the conditioning and power amplifier circuit 17, and the coating corrosion aging monitoring probe 5 is connected to the single-chip microcontroller 11 through the filtering / compensation circuit 18 and the A / D data collector 19 to form a loop; wherein, the computer terminal 3 is connected to the single-chip microcontroller 11 through the communication interface circuit 13, and the set program and parameters are stored in the single-chip microcontroller 11. After the communication is disconnected, the single-chip microcontroller 11 is awakened by the timing clock 12 according to the set program and parameters to work; the memory 15 and the signal generator 16 are connected to each other.

[0043] The power supply module 2 involved in this embodiment includes a solar panel and a battery connected thereto. The battery stores the electric energy generated by the solar panel and directly provides electric energy for the online measurement and transmission module 1 .

[0044] The computer terminal 3 involved in this embodiment has the function of programming the online measurement and transmission module 1, including parameter setting, time correction, and remote data reception.

[0045] The coating corrosion aging monitoring probe 5 involved in this embodiment is closely attached to the surface of the coating 4 to be tested, and the matching environmental monitoring probe 6 corresponding to it is installed near it to perform in-situ electrochemical measurement on the coating 4 to be tested and monitor the environmental parameters around it;

[0046] The main structure of the coating corrosion aging monitoring probe 5 is as follows Figure 3-5 As shown, it includes an outer shell 50 and an inner core 51; the inner core 51 of the ring-shaped outer shell 50 is arranged inside the inner core 51 of the mesh structure, and the two are fixedly connected but not connected, wherein:

[0047] The top of the housing 50 is provided with an inert metal layer 52 of an annular structure, the bottom is provided with an ion conductive layer 53 of an annular structure, and an electrolyte solution 54 is provided between the two;

[0048] The outer shell 50 is provided with an insulating layer 55 on the surface except the ion conductive layer 53, and a reference electrode 56 is provided in the electrolyte solution 54;

[0049] The inert metal layer 52 and the reference electrode 56 are respectively connected to a conductive lead 57, and the conductive lead 57 passes through the insulating layer 55;

[0050] An electrolyte solution 54 is disposed inside the inner core 51, an inert metal layer 52 having a grid structure is disposed in the electrolyte solution 54, and an ion conductive head 58 is disposed at the bottom of the intersection of the grid structure;

[0051] The inner core 51 is provided with an insulating layer 55 except for the surface of the ion conductive head 58;

[0052] The inert metal layer 52 is connected to a conductive lead 57, and the conductive lead 57 passes through the insulating layer 55;

[0053] An elastic member 59 is provided between the insulating layer 55 and the ion conducting head 58 .

[0054] The coating corrosion aging monitoring probe 5 involved in this embodiment is in the shape of a circular ring with a (long) rectangular cross section, with an inner diameter greater than 10 mm and a height less than 6 mm, so as to obtain a sufficient area of ​​the test surface of the coating 4 to be tested;

[0055] The material of the inert metal layer 52 is Pt;

[0056] The ion conducting layer 53 and the ion conducting head 58 are both conductive ceramics;

[0057] The insulating layer 55 is a highly light-transmitting super-hydrophobic plastic or glass to reduce the absorption of ultraviolet light and the influence of long-term monitoring on the state of the coating 4 to be tested;

[0058] The reference electrode 57 is a filamentary Ag / AgCl solid-state reference electrode to establish a stable three-electrode test system.

[0059] The coating corrosion aging state in-situ monitoring device involved in this embodiment tests the epoxy coating (according to the type of resin of the film-forming material, the coating is divided into alkyd coating, acrylic coating, epoxy coating, etc.), and the specific process is as follows:

[0060] (1) Prepare a steel-based epoxy coating sample as the coating to be tested 4, carry out salt spray + UV accelerated aging tests of different cycles, take out the coating to be tested 4 regularly under normal temperature reference conditions (25°C, 90% RH), use an electrochemical workstation to test the low-frequency impedance (0.1 Hz), draw an impedance evolution curve over time, and determine the corresponding accelerated aging time based on the impedance division points of different coating states disclosed in Chinese Patent 202211446054.1, and obtain the impedance division points (10 9 Ω·cm 2 , 10 8 Ω·cm 2 , 10 7 Ω·cm 2 , 10 6 Ω·cm 2 ) corresponding to the coating to be tested 4;

[0061] (2) measuring the DC impedance of the coating 4 under 60% RH, 70% RH, 80% RH, 90% RH and seawater conditions at temperatures of 10°C, 20°C, 30°C and 40°C, respectively, and establishing a relationship between environment-impedance-aging state as a basis for evaluation;

[0062] (3) The coating corrosion and aging monitoring probe 5 is fixedly attached to the surface of the coating 4 to be tested, and the environmental monitoring probe 6 is installed to obtain the temperature, humidity and pressure parameters near the coating corrosion and aging monitoring probe 5, wherein the pressure value is used to determine whether the ambient air or seawater environment;

[0063] (4) Input the coating type and test parameters through the computer terminal 3, control the DC impedance and surrounding environment parameters of the coating 4 to be tested at the test coating corrosion aging monitoring probe 5, and the single-chip microcontroller 11 automatically selects the aging state criterion of the coating system under the temperature, humidity and seawater environment conditions that is closest to the temperature, humidity and pressure information, and gives the accurate aging state of the coating 4 to be tested in combination with the DC impedance measurement value;

[0064] Among them, when the substrate of the coating to be tested 4 is steel, a strong magnetic material is added between the insulating layer 55 and the inert metal layer 52. When used, the coating corrosion aging monitoring probe 5 is tightly attached to the surface of the coating to be tested 4 through magnetic force for corrosion monitoring, and the installation is very convenient. When the substrate of the coating to be tested 4 is other materials, the coating corrosion aging monitoring probe 5 is tightly fixed to the surface of the coating to be tested 4 by means of bow clamps, bundling, etc.

Claims

1. An in-situ monitoring device for coating corrosion and aging, characterized in that: The main structure includes an online measurement and transmission module and a power supply module, a computer terminal, a coating corrosion and aging monitoring probe and an environmental monitoring probe respectively connected thereto, wherein the coating corrosion and aging monitoring probe is arranged on the coating to be tested, and the environmental monitoring probe is arranged near the coating corrosion and aging monitoring probe.

2. The coating corrosion aging state in-situ monitoring device according to claim 1 is characterized in that: The main structure of the line measurement and transmission module includes a single-chip microcontroller and a timing clock, a communication interface circuit, a wireless transmission unit, a memory and a signal generator connected thereto respectively.

3. The coating corrosion aging state in-situ monitoring device according to claim 2 is characterized in that: The power supply module includes a solar panel and a storage battery connected thereto.

4. The coating corrosion aging state in-situ monitoring device according to claim 3 is characterized in that: The main structure of the coating corrosion aging monitoring probe includes an outer shell and an inner core arranged inside the outer shell.

5. An in-situ monitoring device for coating corrosion and aging according to any one of claims 2 to 4, characterized in that: The communication interface circuit is connected to the computer terminal, the memory and the signal generator are connected to each other, the signal generator is connected to the coating corrosion aging monitoring probe through the conditioning and power amplifier circuit, and the coating corrosion aging monitoring probe is connected to the single-chip microcontroller through the filtering / compensation circuit and the A / D data collector to form a loop.

6. The coating corrosion aging state in-situ monitoring device according to claim 4 is characterized in that: An inert metal layer is arranged on the top of the outer shell, an ion conductive layer is arranged on the bottom, an electrolyte solution is arranged between the two, an insulating layer is arranged on the surface of the outer shell except the ion conductive layer, and a reference electrode is arranged in the electrolyte solution; an electrolyte solution is arranged inside the inner core, an ion conductive head is arranged on the bottom, an insulating layer is arranged on the surface of the inner core except the ion conductive head, an inert metal layer is arranged in the electrolyte solution, and an elastic telescopic part is arranged between the insulating layer and the ion conductive head; the inert metal layer and the reference electrode are respectively connected to conductive leads, and the conductive leads pass through the insulating layer.

7. The coating corrosion aging state in-situ monitoring device according to claim 6 is characterized in that: The wireless transmission unit is based on GSM mobile communication technology and uses SMS or GPRS mode for encrypted remote data communication; the signal generator concurrently outputs 4 excitation signals to support the synchronous measurement of 4 groups of coating corrosion and aging monitoring probes; the ion conductive layer and the ion conductive head are both solid hydrophilic ion conductors; the insulating layer is a transparent hydrophobic insulating layer; and the reference electrode is a solid reference electrode.

8. The coating corrosion aging state in-situ monitoring device according to claim 5 is characterized in that: When not in use, the root of the ion conductive head is retracted into the inner core, and the head exceeds the bottom surface of the outer shell; When in use, the coating corrosion aging monitoring probe is fixedly attached to the surface of the coating to be tested, and the ion conductive head simultaneously contacts the surface of the coating to be tested and retracts into the inner core.

9. The coating corrosion aging state in-situ monitoring device according to claim 5, characterized in that: During the measurement, in the humid marine atmosphere, the defects of the coating to be tested absorb moisture and electrolytes, so that the inert metal layer in the outer shell, the reference electrode and the inert metal layer in the inner core in contact with it form a three-electrode system. The polarization potential is applied to scan in the positive or negative direction at a set speed to obtain a polarization curve. The slope of the curve is the DC impedance of the coating to be tested. The magnitude of the DC impedance value represents the aging degree of the coating to be tested. In this process, after the signal generator receives the instruction of the single-chip microcontroller, it simultaneously outputs 4 electrical signals, which are applied to several coating corrosion aging monitoring probes through the conditioning and power amplifier circuit. The coating to be tested produces The generated polarization potential and polarization current are sent to the A / D data acquisition device through the filtering / compensation circuit. The single-chip microcontroller processes several groups of polarization potential and polarization current data collected synchronously, stores them in the memory after analysis, and transmits them back to the computer terminal through the wireless transmission unit. At the same time, the single-chip microcontroller outputs instructions to control the environmental monitoring probe to measure in real time and continuously, and collects and stores the temperature, humidity, pressure and other measurement data of the environment in which the coating corrosion and aging monitoring probe bound to it is located. The single-chip microcontroller associates the DC impedance of the coating to be tested with its surrounding environmental parameters to comprehensively evaluate the aging status of the coating.

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