Fuzzy temperature control test system and method for electrochemical corrosion of aircraft structural materials

Abstract

The present invention relates to the field of detection of electrochemical corrosion of aircraft structural materials, and in particular to a fuzzy temperature control test system and method for electrochemical corrosion of aircraft structural materials. The test system includes a corrosion pool, one side of the corrosion pool is connected to a gas supply device, and the other side is connected to an exhaust liquid device; the corrosion pool is connected to a temperature measuring element, a heating element and a three-electrode element; the temperature measuring element transmits the measured temperature of the corrosion liquid and the room temperature to a temperature control workstation, and a touch screen display adjusts the switch and power of the heating element by controlling the temperature control workstation to make the corrosion liquid reach a predetermined temperature; one end of the three-electrode element is connected to the corrosion liquid, and the other end is connected to the electrochemical workstation, and the electrochemical workstation is connected to the touch screen display and displays the test results, which can quickly and accurately meet the temperature requirements and rapid cooling of the electrochemical corrosion of the sample; it is suitable for the field of electrochemical corrosion behavior testing and technical evaluation of samples under different corrosive gases, different corrosive liquids, different temperatures and other test environments.

Description

Technical Field

[0001] The invention relates to the field of detection of electrochemical corrosion of aircraft structural materials, and in particular to a fuzzy temperature control test system and method for electrochemical corrosion of aircraft structural materials. Background Art

[0002] Electrochemical corrosion of metal materials is widely present in almost all fields of industrial production and living facilities. Among them, the fields with the most serious electrochemical corrosion of metals include modern industries such as petrochemicals, aerospace, shipbuilding, and nuclear energy.

[0003] Metal electrochemical corrosion refers to the damage caused by the electrochemical reaction between the metal surface and the electrolyte solution. In the reaction process, not only does a redox reaction occur, but also an electric current is generated.

[0004] Aircraft structures are extremely susceptible to the changing and harsh service environment during service, and suffer slow corrosion damage. This damage is highly concealed, accidental, and severely destructive. Damage occurring at structural connections will seriously affect the safety and reliability of the aircraft. Therefore, in order to improve the corrosion resistance of aircraft structural materials, it is crucial to accurately and reliably detect the corrosion state of aircraft structural materials.

[0005] Among them, the electrochemical corrosion test system is mainly composed of a corrosion cell, a three-electrode system, a fuzzy temperature control system, etc. The main disadvantages of the traditional electrochemical corrosion system and the improvement method of this patent include:

[0006] (1) The traditional electrochemical corrosion test device uses water (oil) bath heating, which has a slow heating rate and low temperature control accuracy.

[0007] (2) The height of the cell cover mounting element in the conventional electrochemical device is difficult to adjust within the corrosion cell.

[0008] (3) The working electrode and reference electrode in the traditional electrochemical device are isolated. Before the experiment, the experimenter needs to constantly adjust the position of the two electrodes to meet the requirements of the corrosion surface of the sample and the center of the Luggin capillary.

[0009] (4) The critical pitting temperature test requires the liquid to be heated at a uniform rate to test the temperature at which electrochemical corrosion occurs. This requires high temperature control accuracy. Currently, no company in China has launched a corresponding product. Summary of the invention

[0010] The present invention provides a fuzzy temperature control test system and method for electrochemical corrosion of aircraft structural materials to solve the technical problems existing in the known technology. Without introducing other impurities, the corrosion environment of the sample is heated to a specific temperature according to certain requirements to provide the required experimental environment for the electrochemical corrosion test of the sample.

[0011] A fuzzy temperature control test system for electrochemical corrosion of aircraft structural materials, comprising a corrosion pool, an air supply device, an exhaust liquid device, a temperature measuring element, a heating element, a three-electrode element, an electrochemical workstation, a touch screen display and a temperature control workstation; one side of the corrosion pool is connected to the air supply device so that acidic gas or nitrogen enters the corrosion pool liquid, and the other side of the corrosion pool is connected to the exhaust liquid device so as to discharge waste gas and waste liquid; the corrosion pool comprises a corrosion pool cover and a corrosion pool body which are threadedly connected as one body, and the corrosion pool is connected to the temperature measuring element, the heating element and the three-electrode element;

[0012] The temperature measuring element transmits the measured corrosion liquid temperature and room temperature to the temperature control workstation, and the touch screen display adjusts the switch and power of the heating element by controlling the temperature control workstation to make the corrosion liquid reach the predetermined temperature; one end of the three-electrode element is connected to the corrosion liquid, and the other end is connected to the electrochemical workstation, and the electrochemical workstation is connected to the touch screen display, and the touch screen display displays the test results.

[0013] As a preferred technical solution, the gas supply device includes a gas supply pipeline, a gas supply one-way valve, a gas supply pump body, a gas supply switch valve and a gas supply bottle; one side of the corrosion pool is connected to the gas supply one-way valve, the gas supply pump body, the gas supply switch valve and the gas supply bottle in sequence through the gas supply pipeline; after the gas supply one-way valve is switched on, under the action of the gas supply pump body, the acidic gas or nitrogen in the gas supply bottle enters the corrosion pool liquid through the gas supply one-way valve to provide a test environment for the sample.

[0014] As a preferred technical solution, the exhaust liquid device includes an exhaust pipe, an exhaust one-way valve, an exhaust pump body, an exhaust valve, a gas collecting bottle, a discharge pipe and a liquid collecting bottle; the other side of the corrosion pool is connected to the exhaust one-way valve, the exhaust pump body, the exhaust valve and the gas collecting bottle in sequence through the exhaust pipe; after the experiment, the exhaust valve is opened, and the acidic gas enters the gas collecting bottle containing the alkaline neutralizing liquid through the exhaust pipe; the bottom of the corrosion pool body is connected to the liquid collecting bottle through the discharge pipe, and the controllable valve on the discharge pipe is opened to allow the corrosive liquid to flow into the liquid collecting bottle.

[0015] As a preferred technical solution, the temperature measuring element includes a first temperature sensor, a second temperature sensor and a thermometer; the temperature measuring end of the first temperature sensor is immersed in the corrosive liquid of the corrosion pool to test the temperature of the corrosive liquid; the second temperature sensor is connected to the outside of the corrosion pool to measure the room temperature; the heating element is used to increase the temperature of the corrosive liquid; the three-electrode element includes a working reference integrated electrode and an auxiliary electrode.

[0016] As a preferred technical solution, two electrode mounting holes are provided at the center of the pool cover; four heating element mounting holes cooperating with the heating element are evenly distributed on the pool cover and located around the two electrode mounting holes; the first temperature sensor mounting hole and the thermometer mounting hole are symmetrically distributed on both sides of the two electrode mounting holes, and the exhaust holes and the air supply holes are symmetrically arranged on the other two sides of the two electrode mounting holes; an auxiliary electrode mounting hole is provided between the air supply hole of the pool cover and the two electrode mounting holes.

[0017] As a preferred technical solution, the working reference integrated electrode includes a working electrode, a reference electrode and two electrode connectors.

[0018] As a preferred technical solution, the working electrode includes an outer shell, a rubber gasket, a sample, an elastic guide pin and a threaded pressure piece; the outer shell includes an internal threaded hole for connecting to the threaded pressure piece, one end of the threaded hole is open, and the other end is provided with a hole bottom with a small hole; two protrusions are provided on opposite sides of the outer side of the outer shell, and two connecting holes parallel to the internal threaded hole are provided on the protrusions; the sample is installed in the internal threaded hole of the outer shell, and the side of the sample contacting the corrosive liquid contacts the rubber gasket, and the side of the sample not contacting the corrosive liquid contacts the threaded pressure piece, so that the sample is pressed against the rubber gasket by the threaded pressure piece and the outer shell thread cooperation; an elastic guide pin is axially installed inside the threaded pressure piece, one end of the elastic guide pin contacts the sample, and the other end is immersed in the corrosive liquid when in use.

[0019] As a preferred technical solution, the two-electrode connector is used to connect the reference electrode and the working electrode, and specifically includes a connector with a bolt connector and a connector fixed at its bottom end, the bolt connector and the connector are jointly provided with an internal connecting hole for connecting the reference electrode; the bolt connector has an external thread for connecting with the two electrode mounting holes; a connecting column is fixed on the opposite sides of the connector, each connecting column has a through hole inside, and when in use, the two connecting columns correspond to the positions of the two protrusions on the outer shell, the head of each working electrode is arranged in the through hole of one of the connecting columns, the bottom is threadedly connected to the protrusion connecting hole corresponding to the connecting column, and the bottom of the working electrode is tightened and fixed by a nut made of inert material.

[0020] As a preferred technical solution, the test method of the above-mentioned aircraft structural material electrochemical corrosion fuzzy temperature control test system has the following steps:

[0021] Step 1: clean the corrosion tank body, dehydrate and blow dry, and put it in a drying oven for standby use;

[0022] Step 2: Place the sample into the internal threaded hole of the working electrode housing, adjust the thread length to compress the rubber gasket, make the rubber gasket in close contact with the sample, and make the spring guide pin in good contact with the sample; connect and fix the working electrode and the reference electrode through two electrode connectors and inert material nuts; finally, install the assembled working reference integrated electrode in the center of the corrosion cell cover;

[0023] Step 3: Thread the corrosion pool cover onto the corrosion pool body, and then install the temperature measuring element and the three-electrode element on the pool cover in sequence;

[0024] Step 4: With the gas supply switch valve and the exhaust valve closed, connect one end of the gas supply pipe to the gas supply hole of the pool cover, and extend the other end of the pipe into the gas supply bottle filled with nitrogen; connect one end of the exhaust pipe to the exhaust hole of the pool cover, and connect the other end to the gas collection bottle;

[0025] Step 5: Open the air supply switch valve, and under the action of the air supply pump body, pass nitrogen into the corrosion pool body through the air supply pipeline; after one minute, open the exhaust valve, and discharge the mixed air into the gas collection bottle through the exhaust check valve and the exhaust pump body; after one minute of exhaust, close the exhaust pump body, the exhaust switch valve, the air supply pump body and the air supply switch valve in turn;

[0026] Step 6: Replace the gas supply bottle, open the gas supply switch valve, and under the action of the gas supply pump body, pass the corrosive liquid into the corrosion pool through the gas supply pipeline, and then close the gas supply pump body and the gas supply switch valve in turn; replace the acid gas supply bottle, open the gas supply switch valve, and under the action of the gas supply pump body, pass the acid gas into the corrosion pool through the gas supply pipeline;

[0027] Step 7. Turn on the power of the touch screen display, the temperature control workstation and the electrochemical workstation in turn, and check whether the temperature value of the etching solution displayed on the touch screen display is consistent with the value read by the thermometer; after checking that they are consistent, input the final required temperature through the touch screen display, and the touch screen display generates a corresponding control signal by controlling the temperature control workstation to adjust the switch and power of the heating element, and observe the display page of the touch screen display and wait for the temperature to rise;

[0028] Step 8: When the current curve in the display page of the touch screen display changes sharply, the test is over; first, turn off the power of the temperature control workstation and the power of the electrochemical workstation in turn; then, turn off the gas supply pump body and the gas supply switch valve; finally, open the controllable valve on the drainage pipe of the corrosion pool body to let the corrosion liquid flow into the liquid collection bottle;

[0029] Step 9: Remove the connectors on the corrosion tank in turn, clean the corrosion tank body, dehydrate and blow dry, and put it into a drying oven for use.

[0030] The advantages and positive effects of the present invention are:

[0031] The traditional electrochemical corrosion test device adopts water (oil) bath heating, which has a slow heating speed and low temperature control accuracy. The present invention adopts the method of directly heating the corrosion solution with a heating element to speed up the temperature rise of the corrosion solution, and improves the temperature control accuracy by optimizing the installation position of the heating element, temperature sensor, sample, etc. and optimizing the fuzzy temperature control algorithm; at the same time, the heating element, sensor and other components are prevented from being corroded by adding sleeves and seals;

[0032] The height of the cell cover mounting element in the corrosion cell of the traditional electrochemical device is difficult to adjust. In this device, a two-electrode connector for mounting heating elements, temperature sensors and other elements is used to adjust the height of each fixing element in the liquid by changing the length of the thread matching between the two-electrode connector and the threaded hole of the cell cover.

[0033] The working electrode and reference electrode in the traditional electrochemical device are separated. Before the experiment, the experimenter needs to constantly adjust the position of the two electrodes to meet the requirements of the corrosion surface of the sample and the center of the Luggin capillary. In this device, the working electrode and the reference electrode are integrated through the threaded fit of the two electrode connectors and the inert material nut. The position of the working electrode and the reference electrode does not need to be adjusted many times before the experiment, and the installation process is convenient;

[0034] The critical pitting temperature test requires the temperature at which electrochemical corrosion occurs to be tested by uniformly increasing the temperature of the liquid, which requires high temperature control accuracy. Currently, no company in China has launched a corresponding product. The temperature control system for uniformly increasing the temperature of the corrosive liquid designed by the present invention can be used to determine the critical pitting temperature of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the corrosion pool structure of the device of the present invention;

[0036] Figure 2 It is a connection diagram of various systems of the device of the present invention;

[0037] Figure 3 A top view of the corrosion pool cover of the device of the present invention;

[0038] Figure 4 This is an overall diagram of the working reference integrated electrode of the device of the present invention;

[0039] Figure 5 An exploded view of a working reference integrated electrode of the device of the present invention;

[0040] Figure 6 It is the structural diagram of the temperature control system of the device of the present invention.

[0041] In the figure above: 1. Corrosion pool cover; 2. First temperature sensor; 3. Working integrated electrode; 4. Auxiliary electrode; 6. Gas supply pipeline; 7. Thermometer; 8. Corrosion pool body; 91. Exhaust pipeline; 92. Drain pipeline; 10. Second temperature sensor; 11. Gas supply bottle; 12. Gas supply switch valve; 13. Gas supply pump body; 14. Gas supply check valve; 15. Temperature measuring element; 16. Heating element; 17. Three-electrode element; 18. Exhaust check valve; 19. Exhaust pump body; 20. Exhaust valve; 21. Gas collection bottle; 22. Temperature control workstation; 23. Electrochemical workstation; 24. Touch screen display ; 25. Heating element mounting hole; 26. Exhaust hole; 27. Two-electrode mounting hole; 28. First temperature sensor mounting hole; 29. ​​Air supply hole; 30. Auxiliary electrode mounting hole; 31. Thermometer mounting hole; 32. Reference electrode; 33. Two-electrode connecting piece; 33-a. Bolt connector; 33-b. Connector; 33-c. Connecting column; 34. Inert material nut; 35. Working electrode housing; 35-a. Bump; 36. Rubber gasket; 37. Sample; 38. Elastic guide pin; 39. Threaded pressure piece; 40. Working electrode; 41. Thermal resistor module; 42. PLC; 43. Solid-state relay. DETAILED DESCRIPTION

[0042] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0043] See also Figures 1 to 6 A fuzzy temperature control test system and method for electrochemical corrosion of aircraft structural materials includes a corrosion cell, an air supply device, an exhaust liquid device, a temperature measuring element 15, a heating element 16, a three-electrode element 17, an electrochemical workstation 23, a touch screen display 24 and a temperature control workstation 22.

[0044] The gas supply device includes a gas supply pipeline 6, a gas supply one-way valve 14, a gas supply pump body 13, a gas supply switch valve 12 and a gas supply bottle 11; the exhaust liquid device includes an exhaust pipeline 91, an exhaust one-way valve 18, an exhaust pump body 19, an exhaust valve 20, a gas collecting bottle 21, a liquid discharge pipeline 92 and a liquid collecting bottle.

[0045] One side of the corrosion pool is connected to the gas supply check valve 14, the gas supply pump body 13, the gas supply switch valve 12 and the gas supply bottle 11 in sequence through the gas supply pipeline 6, and the other side is connected to the exhaust check valve 18, the exhaust pump body 19, the exhaust valve 20 and the gas collection bottle 21 in sequence through the exhaust pipeline 91. The gas in the gas supply bottle 11 is acidic gas or nitrogen. Among them, the acidic gas provides an acidic corrosion environment for the experimental sample 37, and the nitrogen is used to remove the oxygen in the corrosion bottle to avoid affecting the test results. After the switch of the gas supply check valve 14 is turned on, under the action of the gas supply pump body 13, the acidic gas or nitrogen in the gas supply bottle 11 enters the corrosion pool liquid through the gas supply check valve 14 to provide a test environment for the sample 37. After the experiment is over, the exhaust valve 20 is opened, and the acidic gas enters the gas collection bottle 21 containing the alkaline neutralization liquid through the exhaust pipeline. The controllable valve on the drainage pipeline 92 is opened to allow the corrosive liquid to flow into the liquid collection bottle.

[0046] In addition, the corrosion pool includes a corrosion pool cover 1 and a corrosion pool body 7 that are threaded together as one, and the corrosion pool is connected with a temperature measuring element 15, a heating element 16 and a three-electrode element 17; the temperature measuring element 15 includes a first temperature sensor 2, a second temperature sensor 10 and a thermometer; the heating element 16 is used to increase the temperature of the corrosion liquid; the three-electrode element 17 includes a working reference integrated electrode and an auxiliary electrode 4.

[0047] The temperature measuring end of the first temperature sensor 2 is immersed in the corrosive liquid of the corrosion pool to test the temperature of the corrosive liquid; the second temperature sensor 10 is connected to the outside of the corrosion pool to measure the room temperature; specifically, the first and second temperature sensors of the present invention are both industrial grade A PT100 platinum resistance temperature sensors, whose temperature measurement range is -200℃~850℃, and the allowable temperature deviation is ±(0.15+0.002|t|)℃. The temperature control workstation 22 is composed of a thermal resistor module, a PLC, a solid-state relay, etc. The touch screen display 24 transmits the control signal to the PLC through Ethernet, and the PLC controls the heating rate of the heating element 16 by controlling the solid-state relay, thereby controlling the temperature collection and transmission and the heating of the liquid in the corrosion pool. Among them, the present invention uses the PLC expandable Siemens thermal resistance module EMAR02 as the signal processing module of the PT100 platinum resistance temperature sensor, which can directly convert the resistance value into the temperature value with a resolution of 0.1°C; the PLC model used in the present invention is CPU ST20 DC / DC / DC, with a power supply voltage of 24V, 12 input ports, and 8 output ports; the present invention uses a DC-controlled DC solid-state relay with a control voltage of 3-32VDC, a load voltage of 12-220VDC, and an output current of 25A. The heating element 16 is a heating rod.

[0048] The first and second temperature sensors 10 convert the collected analog signals into digital signals that can be processed by the PLC through the thermal resistance module, and transmit them to the temperature control workstation 22 for temperature control algorithm calculation. The specific temperature control algorithm belongs to the prior art, and there are many references, which will not be repeated here. The display 24 generates corresponding control signals by controlling the temperature control workstation 22 to adjust the switch and power of the heating element 16. One end of the three-electrode element 17 is installed on the pool cover, and the other end is connected to the electrochemical workstation 23. The electrochemical workstation 23 is connected to the touch screen display 24, and the touch screen display 24 displays the test results. Two electrode mounting holes 27 are provided at the center of the pool cover; four heating element mounting holes 25 cooperating with the heating element 16 are evenly distributed on the pool cover and are located around the two electrode mounting holes 27, so as to ensure that the corrosive liquid is heated more evenly; the first temperature sensor mounting hole 28 and the thermometer mounting hole 31 are symmetrically distributed on both sides of the two electrode mounting holes 27. By comparing the temperature value difference between the thermometer and the PT100 temperature sensor with the temperature measuring end immersed in the corrosive liquid, the accuracy of the temperature measurement of the PT100 temperature sensor can be checked; the exhaust holes 26 and the air supply holes 29 are symmetrically arranged on the other two sides of the two electrode mounting holes 27; an auxiliary electrode mounting hole 3 is provided between the pool cover air supply hole 29 and the two electrode mounting holes 27. The bottom of the corrosion pool body 7 is connected to the liquid collection bottle through a drainage pipe 92. Preferably, the thermometer and the temperature sensor are symmetrically arranged on both sides of the longitudinal axis of the working reference integrated electrode,

[0049] The working reference integrated electrode comprises a working electrode 40, a reference electrode 32 and two electrode connectors 33. The electrode is integrated, which facilitates the alignment of the sample 37 and the Luggin capillary before the experiment and the installation of the experimental device.

[0050] The working electrode 40 includes a shell 35, a rubber gasket 36, a sample 37, an elastic guide pin 38 and a threaded pressure piece 39; the shell 35 includes an internal threaded hole for connecting with the threaded pressure piece 39, one end of the threaded hole is open, and the other end is provided with a hole bottom with a small hole; two convex blocks 35-a are provided on opposite sides of the outer side of the shell 35, and two connecting holes parallel to the internal threaded hole are provided on the convex blocks 35-a; the sample 37 is installed in the internal threaded hole of the shell 35, and the side of the sample 37 contacting the corrosive liquid contacts the rubber gasket 36, and the side of the sample 37 not contacting the corrosive liquid contacts the threaded pressure piece 39, so that the sample 37 is pressed against the rubber gasket 36 by the threaded cooperation of the threaded pressure piece 39 and the shell 35, thereby reducing the gap between the rubber gasket 36 and the sample 37 and weakening the influence of crevice corrosion. In addition, an elastic guide pin 38 is installed axially inside the threaded pressure piece 39, one end of the elastic guide pin 38 contacts the sample 37, and the other end is immersed in the corrosive liquid when in use. The depth of the working reference integrated electrode inserted into the etching solution is approximately two-thirds of the depth of the etching solution, and in order to reduce the potential error caused by the solution resistance between the Luggin capillary and the metal surface, the lateral distance from the surface of the test sample 37 to the reference electrode 32 does not exceed 6 mm.

[0051] The two-electrode connector 33 is used to connect the reference electrode 32 and the working electrode 40, and specifically includes a bolt connector 33-a and a connector 33-b fixed at the bottom end thereof, the bolt connector 33-a and the connector 33-b are jointly provided with an internal connecting hole for connecting the reference electrode 32; the bolt connector 33-a has an external thread for connecting with the two electrode mounting holes 27; a connecting column 33-c is fixed on the opposite sides of the connector 33-b, and each connecting column 33-c has a through hole inside. When in use, the two connecting columns 33-c correspond to the positions of the two protrusions 35-a on the outer shell 35, the head of each working electrode 40 is arranged in the through hole of one of the connecting columns 33-c, and the bottom is threadedly connected to the corresponding protrusion 35-a connecting hole of the connecting column 33-c, and the bottom of the working electrode 40 is tightened and fixed by an inert material nut 34. Thus, the bolt connection head 33-a and the connection body 33-b of the two electrode connectors 33 are used to fix the reference electrode 32, and the connection column 33-c and the outer shell 35 are used to fix the working electrode 40. When in use, the two electrode connectors 33 should be positioned with the pool cover, and the reference electrode 32, the working electrode 40 and the elastic guide needle 38 should be immersed in the corrosive liquid, saving the connection space on the pool cover.

[0052] Preferably, glass is the structural material of the corrosion pool body 7. Considering the selection of fixtures in the threaded hole processing project for installing the drainage pipe 92 on the side of the pool body, the pool body is designed to be a rectangular parallelepiped. Considering the requirements of thread sealing, the threaded mating part of the upper end of the corrosion pool body 7 is designed to be cylindrical, and the thread on the upper end of the pool body is processed into an external thread. The sealing between the glass pool body and the pool cover is achieved through thread matching and a circular rubber sealing ring.

[0053] Among them, the connecting parts on the corrosion tank that are in contact with the corrosion liquid, the shell 35 of the working electrode 40, and the threaded pressure piece 39 are all made of inert materials.

[0054] Preferably, the entire corrosion pool is wrapped with a heat-insulating jacket to reduce heat loss.

[0055] Preferably, each connector connected to the corrosion pool is made of corrosion-resistant inert material. The heating element 16 and the first and second temperature sensors 10 are sleeved in a corrosion-resistant heat-conducting thin-walled sleeve filled with heat-conducting material.

[0056] Preferably, the plugs and sealing rings of the corrosion tank, the gas supply bottle 11 and the gas collection bottle 21 are made of silicone rubber as the structural material because of its good elasticity and stability.

[0057] Preferably, the gas collection bottle 21 is filled with sodium hydroxide solution, which is used to neutralize the collected acidic gas to protect the environment.

[0058] Preferably, the instructions sent by the touch screen display 24 to the PLC include: reading the temperature of the etching liquid, the room temperature, the power of the heating element 16, setting the temperature, starting and stopping the constant temperature control, starting and stopping the temperature rise control, etc.

[0059] Preferably, the instructions sent by the PLC to the touch screen display 24 include: sending the temperature of the corrosive liquid, sending the room temperature measured by the room temperature measuring liquid temperature sensor, etc.

[0060] The specific testing steps of the present invention are as follows:

[0061] Step 1: Use a cotton brush and distilled water to carefully clean the corrosion pool body 7 for more than two times, then use anhydrous ethanol to dehydrate and blow dry, and put it in a drying oven for standby use;

[0062] Step 2: Place the sample 37 into the internal threaded hole of the working electrode 40 housing 35, with one side of the sample 37 in contact with the rubber gasket 36 and one side facing the threaded pressure piece 39; thread the threaded pressure piece 39 and the working electrode 40 housing 35, adjust the thread matching length to press the rubber gasket 36, so that the rubber gasket 36 is in close contact with the sample 37, and the spring guide pin is in good contact with the sample 37; connect and fix the working electrode 40 and the reference electrode 32 through two electrode connectors 33 and inert material nuts; finally, install the assembled working reference integrated electrode in the center of the corrosion pool cover 1;

[0063] Step 3, thread the corrosion pool cover onto the corrosion pool body 7, and then sequentially install the first and second temperature sensors 10, the thermometer, the four heating elements 16 and the three-electrode element 17 onto the pool cover;

[0064] Step 4: When the gas supply switch valve 12 and the exhaust valve 20 are closed, connect one end of the gas supply pipe 6 to the gas supply hole 29 of the pool cover, and extend the other end of the pipe into the gas supply bottle 11 filled with nitrogen; connect one end of the exhaust pipe 91 to the exhaust hole 26 of the pool cover, and connect the other end to the gas collection bottle 21;

[0065] Step 5, open the air supply switch valve 12, and under the action of the air supply pump body 13, nitrogen is introduced into the corrosion tank body 7 through the air supply pipe 6; about one minute later, open the exhaust valve, and discharge the mixed air into the gas collection bottle 21 through the exhaust check valve 18 and the exhaust pump body 19; after exhausting for one minute, close the exhaust pump body 19, the exhaust valve 20, the air supply pump body 13 and the air supply switch valve 12 in sequence;

[0066] Step 6: Replace the gas supply bottle 11, open the gas supply switch valve 12, and under the action of the gas supply pump body 13, pass the corrosive liquid into the corrosion tank body 7 through the gas supply pipeline 6, and then close the gas supply pump body 13 and the gas supply switch valve 12 in turn; replace the acid gas supply bottle 11, open the gas supply switch valve 12, and under the action of the gas supply pump body 13, pass the acid gas into the corrosion tank body 7 through the gas supply pipeline 6;

[0067] Step 7, turn on the power of the touch screen display 24, the temperature control workstation 22 and the electrochemical workstation 23 in turn, check whether the temperature value of the etching solution displayed on the touch screen display 24 is consistent with the value read by the thermometer; after checking that they are consistent, input the final required temperature through the touch screen display 24, and the touch screen display 24 generates a corresponding control signal by controlling the temperature control workstation 22 to adjust the switch and power of the heating element 16, and observe the display page of the touch screen display 24 and wait for the temperature to rise;

[0068] Step 8: When the current curve in the display page of the touch screen display 24 changes sharply, the test is finished; first, turn off the power of the temperature control workstation 22 and the power of the electrochemical workstation 23 in turn; then, turn off the gas supply pump body 13 and the gas supply switch valve 12; finally, open the controllable valve on the drainage pipe 92 of the corrosion pool body 7, and carefully let the corrosion liquid flow into the liquid collection bottle;

[0069] Step 9: Remove the connectors on the corrosion pool in turn, then use a cotton brush and distilled water to carefully clean the corrosion pool body 7 more than twice, finally use anhydrous ethanol to dehydrate and blow dry, and put it in a drying oven for use.

[0070] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments, which are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which belong to the scope of protection of the present invention.

Claims

1. A fuzzy temperature control test system for electrochemical corrosion of aircraft structural materials, characterized by: It includes a corrosion tank, a gas supply device, a liquid exhaust device, a temperature measuring element, a heating element, a three-electrode element, an electrochemical workstation, a touch screen display and a temperature control workstation; One side of the corrosion pool is connected to a gas supply device so that acidic gas or nitrogen can enter the liquid in the corrosion pool, and the other side of the corrosion pool is connected to a liquid exhaust device so as to exhaust waste gas and waste liquid; The corrosion pool comprises a corrosion pool cover and a corrosion pool body which are threadedly connected as one body, and the corrosion pool is connected with a temperature measuring element, a heating element and a three-electrode element; The temperature measuring element transmits the measured temperature of the corrosion liquid and the room temperature to the temperature control workstation, and the touch screen display adjusts the switch and power of the heating element by controlling the temperature control workstation to make the corrosion liquid reach a predetermined temperature; one end of the three-electrode element is connected to the corrosion liquid, and the other end is connected to the electrochemical workstation, and the electrochemical workstation is connected to the touch screen display, and the touch screen display displays the test results; The exhaust liquid device comprises an exhaust pipeline, an exhaust check valve, an exhaust pump body, an exhaust valve, a gas collection bottle, a discharge pipeline and a liquid collection bottle; the other side of the corrosion pool is connected to the exhaust check valve, the exhaust pump body, the exhaust valve and the gas collection bottle in sequence through the exhaust pipeline; after the experiment is over, the exhaust valve is opened, and the acidic gas enters the gas collection bottle containing the alkaline neutralizing liquid through the exhaust pipeline; the bottom of the corrosion pool body is connected to the liquid collection bottle through the discharge pipeline, and the controllable valve on the discharge pipeline is opened to allow the corrosive liquid to flow into the liquid collection bottle; The temperature measuring element includes a first temperature sensor, a second temperature sensor and a thermometer; the temperature measuring end of the first temperature sensor is immersed in the corrosive liquid of the corrosion tank to test the temperature of the corrosive liquid; the second temperature sensor is connected to the outside of the corrosion tank to measure the room temperature; the heating element is used to increase the temperature of the corrosive liquid; the three-electrode element includes a working reference integrated electrode and an auxiliary electrode.

2. The aircraft structural material electrochemical corrosion fuzzy temperature control test system according to claim 1, characterized in that: The gas supply device includes a gas supply pipeline, a gas supply one-way valve, a gas supply pump body, a gas supply switch valve and a gas supply bottle; one side of the corrosion pool is connected to the gas supply one-way valve, the gas supply pump body, the gas supply switch valve and the gas supply bottle in sequence through the gas supply pipeline; after the gas supply one-way valve is switched on, under the action of the gas supply pump body, the acid gas or nitrogen in the gas supply bottle enters the corrosion pool liquid through the gas supply one-way valve to provide a test environment for the sample.

3. The aircraft structural material electrochemical corrosion fuzzy temperature control test system according to claim 1, characterized in that: Two electrode mounting holes are provided at the center of the pool cover; four heating element mounting holes cooperating with the heating element are evenly distributed on the pool cover and located around the two electrode mounting holes; the first temperature sensor mounting hole and the thermometer mounting hole are symmetrically distributed on both sides of the two electrode mounting holes, and the exhaust holes and the air supply holes are symmetrically arranged on the other two sides of the two electrode mounting holes; an auxiliary electrode mounting hole is provided between the pool cover air supply hole and the two electrode mounting holes.

4. The aircraft structural material electrochemical corrosion fuzzy temperature control test system according to claim 1, characterized in that: The working reference integrated electrode comprises a working electrode, a reference electrode and two electrode connectors.

5. The aircraft structural material electrochemical corrosion fuzzy temperature control test system according to claim 4, characterized in that: The working electrode comprises an outer shell, a rubber gasket, a sample, an elastic guide pin and a threaded pressure piece; the outer shell comprises an internal threaded hole for connecting with the threaded pressure piece, one end of the threaded hole is open, and the other end is provided with a hole bottom with a small hole; two convex blocks are provided on opposite sides of the outer side of the outer shell, and two connecting holes parallel to the internal threaded hole are provided on the convex blocks; the sample is installed in the internal threaded hole of the outer shell, and the side of the sample contacting the corrosive liquid contacts the rubber gasket, and the side of the sample not contacting the corrosive liquid contacts the threaded pressure piece, so that the sample is pressed against the rubber gasket by the threaded pressure piece and the outer shell thread; an elastic guide pin is axially installed inside the threaded pressure piece, one end of the elastic guide pin contacts the sample, and the other end is immersed in the corrosive liquid when in use.

6. The aircraft structural material electrochemical corrosion fuzzy temperature control test system according to claim 5, characterized in that: The two-electrode connector is used to connect the reference electrode and the working electrode, and specifically includes a connector with a bolt connector and a connector fixed at its bottom end, the bolt connector and the connector are jointly provided with an internal connection hole for connecting the reference electrode; the bolt connector is provided with an external thread for connecting with the two electrode mounting holes; a connecting column is fixed on the opposite sides of the connector, each connecting column is provided with a through hole inside, and when in use, the two connecting columns correspond to the positions of the two protrusions on the outer shell, the head of each working electrode is arranged in the through hole of one of the connecting columns, the bottom is threadedly connected to the protrusion connection hole corresponding to the connecting column, and the bottom of the working electrode is tightened and fixed by a nut made of inert material.

7. A test method for the fuzzy temperature control test system for electrochemical corrosion of aircraft structural materials as claimed in claim 6, characterized in that: Here are the steps: Step 1: clean the corrosion tank body, dehydrate and blow dry, and put it in a drying oven for standby use; Step 2: Place the sample into the internal threaded hole of the working electrode housing, adjust the thread length to compress the rubber gasket, make the rubber gasket in close contact with the sample, and make the spring guide pin in good contact with the sample; connect and fix the working electrode and the reference electrode through two electrode connectors and inert material nuts; finally, install the assembled working reference integrated electrode in the center of the corrosion cell cover; Step 3: Thread the corrosion pool cover onto the corrosion pool body, and then install the temperature measuring element and the three-electrode element on the pool cover in sequence; Step 4: With the gas supply switch valve and the exhaust valve closed, connect one end of the gas supply pipe to the gas supply hole of the pool cover, and extend the other end of the pipe into the gas supply bottle filled with nitrogen; connect one end of the exhaust pipe to the exhaust hole of the pool cover, and connect the other end to the gas collection bottle; Step 5: Open the air supply switch valve, and under the action of the air supply pump body, pass nitrogen into the corrosion pool body through the air supply pipeline; after one minute, open the exhaust valve, and discharge the mixed air into the gas collection bottle through the exhaust check valve and the exhaust pump body; after one minute of exhaust, close the exhaust pump body, the exhaust switch valve, the air supply pump body and the air supply switch valve in turn; Step 6: Replace the gas supply bottle, open the gas supply switch valve, and under the action of the gas supply pump body, pass the corrosive liquid into the corrosion pool through the gas supply pipeline, and then close the gas supply pump body and the gas supply switch valve in turn; replace the acid gas supply bottle, open the gas supply switch valve, and under the action of the gas supply pump body, pass the acid gas into the corrosion pool through the gas supply pipeline; Step 7. Turn on the power of the touch screen display, the temperature control workstation and the electrochemical workstation in turn, and check whether the temperature value of the etching solution displayed on the touch screen display is consistent with the value read by the thermometer; after checking that they are consistent, input the final required temperature through the touch screen display, and the touch screen display generates a corresponding control signal by controlling the temperature control workstation to adjust the switch and power of the heating element, and observe the display page of the touch screen display and wait for the temperature to rise; Step 8: When the current curve in the display page of the touch screen display changes sharply, the test is finished; first, turn off the power of the temperature control workstation and the power of the electrochemical workstation in turn; then, turn off the gas supply pump body and the gas supply switch valve; finally, open the controllable valve on the drainage pipe of the corrosion pool body to let the corrosion liquid flow into the liquid collection bottle; Step 9: Remove the connectors on the corrosion tank in turn, clean the corrosion tank body, dehydrate and blow dry, and put it into a drying oven for use.

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