Experimental device and method for simulating atmospheric corrosion in acid rain environment

Abstract

The invention relates to an experimental device and method for simulating atmospheric corrosion in an acid rain environment. The experimental device comprises a test box, an acid rain solution storage tank, an atomizing nozzle, a circulating fan, an ultraviolet lamp, a liquid level instrument, a temperature and humidity sensor, a driving motor, a filter, an electric valve, a self-sucking pump and a control device, an acid rain solution is arranged at the bottom in the test box, a liquid level instrument and a temperature and humidity sensor are arranged on the inner side, a sample table capable of moving up and down is arranged at the bottom, a circulating fan and an ultraviolet lamp are arranged in the test box, and an atomizing nozzle is arranged at the top; an acid rain solution is arranged in the acid rain solution storage tank, an outlet of the acid rain solution storage tank is connected with an atomizing nozzle through a spraying pipe, a self-priming pump is arranged on the spraying pipe, an inlet of the acid rain solution storage tank is connected with the bottom of the test box through a return pipe, and a filter and an electric valve are arranged on the return pipe; according to the experimental device and method, the acid rain corrosion environment is simulated from a panoramic angle, and the simulation accuracy is enhanced through air circulation, an ultraviolet lamp and the like.

Description

Technical Field

[0001] The invention relates to the technical field of material property testing, and in particular to an atmospheric corrosion experimental device and method for simulating acid rain environment. Background Art

[0002] Acid rain is a type of rainfall or snowfall with a pH value of less than 5.6. It is an extremely harmful atmospheric phenomenon that generally occurs in the south. Acid rain is caused by the development of industry, the burning of fossil fuels, and the emission of automobile exhaust, which emit a large amount of acidic gases such as sulfur dioxide, carbon dioxide, and nitrogen dioxide into the atmosphere. These acidic gases are easily soluble in water and will combine with rain or snow in the air to form acidic substances that settle on the ground, causing large-scale damage to forest trees and vegetation. Generally, acid rain is acidic. Acid rain not only destroys the ecological environment, but also aggravates the corrosion of metals. In 1999, the economic losses caused by acid rain corrosion worldwide reached 20 billion US dollars, and the economic losses caused by acid rain corrosion in my country reached 3 billion US dollars. Therefore, it is of great significance to study the corrosion behavior of metal materials in acid rain environments.

[0003] At present, the research on atmospheric corrosion under acid rain environment mainly adopts electrochemical method and full immersion test method. The electrochemical method is to test the electrochemical curves of the sample in the acid solution. This method can only detect the corrosion resistance of the sample matrix to the acid solution, and cannot observe the rust layer morphology and analyze the rust layer's resistance to acid solution corrosion; the full immersion test method is to immerse the sample in the acid solution for a long time, which can observe the rust layer and calculate the corrosion rate, but because its corrosion conditions are not harsh enough and it cannot accurately simulate the acid rain spraying conditions, the results obtained are limited. Simulating different corrosion environments and evaluating the corrosion resistance of materials and coatings are mainly carried out through weekly immersion tests. For many materials, weekly immersion tests provide a more harsh corrosion test condition than continuous immersion, and the simulation of the corrosion environment is also more accurate. However, there are no reports on the use of weekly immersion tests to simulate the atmospheric corrosion environment of acid rain. Summary of the invention

[0004] The present invention provides an experimental device and method for simulating atmospheric corrosion in an acid rain environment, which not only simulates the acid rain corrosion environment from a panoramic perspective, but also enhances the simulation accuracy through wind circulation, ultraviolet lamps, etc., thereby realizing laboratory simulation of atmospheric corrosion in an acid rain environment.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An atmospheric corrosion experimental device for simulating acid rain environment, comprising a test box, an acid rain solution storage tank, an atomizing nozzle, a circulating fan, an ultraviolet lamp, a liquid level meter, a temperature and humidity sensor, a driving motor, a filter, an electric valve, a self-priming pump and a control device;

[0007] An acid rain solution is arranged at the bottom of the test box, a liquid level meter and a temperature and humidity sensor are arranged inside the test box to monitor the liquid level of the acid rain solution, a sample table that can move up and down is arranged at the bottom of the test box, a circulating fan is arranged in the test box, and the wind force of the circulating fan changes according to the environment, an atomizing nozzle is arranged above the test table at the top of the test box, and the mode and flow rate of atomizing spraying and splashing solution are adjusted according to needs, and an ultraviolet lamp is arranged in the test box;

[0008] Acid rain solution is arranged in the acid rain solution storage tank, the outlet of the acid rain solution storage tank is connected to the atomizing nozzle through a spray pipe, and a self-priming pump is arranged on the spray pipe, and the inlet of the acid rain solution storage tank is connected to the bottom of the test box through a reflux pipe, and a filter and an electric valve are arranged on the reflux pipe;

[0009] The circulating fan, ultraviolet lamp, self-priming pump, temperature and humidity sensor, electric valve and driving motor control signals are connected to the control device.

[0010] Furthermore, the control device includes a first relay, a second relay, a third relay, a fourth relay, a control system and a control box, the opening point of the first relay is connected to the power supply terminal of the self-priming pump, the coil of the first relay is connected to the digital output port of the control system, the opening point of the second relay is connected to the power supply terminal of the electric valve, the coil of the second relay is connected to the digital output port of the control system, the opening point of the third relay is connected to the power supply terminal of the drive motor, the coil of the third relay is connected to the digital output port of the control system, the opening point of the fourth relay is connected to the power supply terminal of the ultraviolet lamp, the coil of the fourth relay is connected to the digital output port of the control system, and the first relay, the second relay, the third relay, the fourth relay and the control system are all arranged in the control box.

[0011] Furthermore, the acid rain solution adopts 0.001-0.02 mol / LNaHSO3, 0.001-0.02 mol / LNaNO3 or (0.001-0.02) mol / LNaHSO3+(0.001-0.02) mol / LNaNO3 at 25°C.

[0012] Furthermore, the sample table is a hollow structure, with the sample tied up in the middle by ropes, the angle of the upper surface of the sample table varies from 30 to 90 degrees, and the lower part of the sample table is connected to the bottom of the test box by a support.

[0013] Furthermore, an anti-corrosion lampshade is arranged outside the ultraviolet lamp.

[0014] A method for simulating atmospheric corrosion in an acid rain environment comprises the following steps:

[0015] S1. Sample pretreatment: Cut the sample to be tested into the required size, polish it step by step with sandpaper, and degrease its surface. After drying, tie the sample to the sample table, adjust the angle of the sample table to make it consistent with the spray angle of the sample during service, adjust the spray mode and flow rate of the atomizing nozzle to meet the service conditions of the sample, and put the prepared acid rain solution into the test box and the acid rain solution storage tank so that the acid rain solution in the test box reaches the set liquid level;

[0016] S2. Equipment parameter setting: according to the requirements of the experimental plan, set the temperature and humidity in the test box and the temperature of the acid rain solution, set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and post-spraying UV lamp irradiation time in a weekly immersion cycle;

[0017] S3, Experimental operation: The equipment power is turned on, the circulating fan is turned on, the wind force is adjusted to the ambient wind force when the sample is in service, the sample table drive motor power is turned on, the sample table is lowered to below the acid rain solution surface, and after being immersed and corroded for a set time, the sample table rises to above the acid rain solution surface, and the ultraviolet lamp is turned on at the same time. After continuous irradiation for a set time, the self-priming pump is turned on. The self-priming pump transports the acid rain solution to the atomizing nozzle through the spray pipe, and starts to spray the sample continuously. After spraying for a set time, the self-priming pump power is cut off. After the ultraviolet lamp irradiates for the required set time, the ultraviolet lamp power is cut off, the ultraviolet lamp is turned off, and the sample table drive motor power is turned on. The sample table is lowered below the acid rain solution surface, and is ready for the next weekly immersion cycle;

[0018] S4. Experimental maintenance: When the liquid level meter in the test chamber detects that the liquid level reaches the maximum value, the control device sends a control command to automatically open the electric valve, and the acid rain solution flows back from the test chamber to the acid rain solution storage tank through the reflux pipe, and the impurities are filtered out by the filter. When the liquid level returns to the set value, the control device closes the electric valve. When the acid rain spray simulation is not carried out in the experiment, and only the acidic atmospheric environment immersion experiment is carried out, or when the equipment is used normally and the liquid level reaches the minimum value, the solution in the test chamber needs to be replenished manually.

[0019] Furthermore, the number of immersion cycles is 24 / n to 360 / n cycles, where n is the total time of one cycle.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1) Introduce the acid spray system into the immersion corrosion test chamber, and enhance the accuracy of the simulated acid rain environment through wind circulation, ultraviolet light, etc., to simulate the acid rain corrosion environment from a panoramic perspective;

[0022] 2) Using this set of atmospheric corrosion immersion experimental equipment in acid rain environment, we designed an experimental research method for atmospheric corrosion in acid rain environment, realized the laboratory simulation of atmospheric corrosion in acid rain environment, and provided strong support for related research. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the device of the present invention.

[0024] Figure 2 It is a schematic diagram of sample suspension on the sample table of the present invention.

[0025] Figure 3 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test in a simulated acid rain environment in Example 1 of the present invention after 24 hours of corrosion.

[0026] Figure 4 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 1 of the present invention at 72 hours of corrosion.

[0027] Figure 5 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 1 of the present invention at 144 hours of corrosion.

[0028] Figure 6 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 1 of the present invention after 240 hours of corrosion.

[0029] Figure 7 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 1 of the present invention after 360 hours of corrosion.

[0030] Figure 8 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test in a simulated acid rain environment in Example 2 of the present invention after 24 hours of corrosion.

[0031] Fig. 9 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 2 of the present invention at 72 hours of corrosion.

[0032] Fig.10 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 2 of the present invention at 144 hours of corrosion.

[0033] Fig.11 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 2 of the present invention after 240 hours of corrosion.

[0034] Fig.12 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 2 of the present invention after 360 hours of corrosion.

[0035] Fig.13It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 3 of the present invention after 24 hours of corrosion.

[0036] Fig.14 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 3 of the present invention at 72 hours of corrosion.

[0037] Fig.15 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 3 of the present invention at 144 hours of corrosion.

[0038] Fig.16 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 3 of the present invention after 240 hours of corrosion.

[0039] Fig.17 It is a schematic diagram of the sample before rust removal in the accelerated atmospheric corrosion test simulating an acid rain environment in Example 3 of the present invention after 360 hours of corrosion.

[0040] In the figure: 1. Self-priming pump 2. Acid rain solution storage tank 3. Test chamber 4. Circulation fan 5. Liquid level meter 6. Acid rain solution 7. Sample table 8. Ultraviolet lamp 9. Atomizing nozzle 10. Control system 11. First relay 12. Second relay 13. Third relay 14. Fourth relay 15. Filter 16. Electric valve 17. Spray pipe 18. Reflux pipe DETAILED DESCRIPTION

[0041] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings:

[0042] See Figure 1 , which is a structural schematic diagram of the present invention. The present invention is a simulated acid rain environment atmospheric corrosion experimental device, comprising a test box 3, an acid rain solution storage tank 2, an atomizing nozzle 9, a circulating fan 4, an ultraviolet lamp 8, a liquid level meter 5, a temperature and humidity sensor, a driving motor, a filter 15, an electric valve 16, a self-priming pump 1 and a control device;

[0043] The bottom of the test box 3 is loaded with an acid rain solution 6, which is 0.001-0.02 mol / LNaHSO3, 0.001-0.02 mol / LNaNO3 or (0.001-0.02) mol / LNaHSO3+(0.001-0.02) mol / LNaNO3 at 25°C, and can be prepared as needed according to the experimental environment;

[0044] A liquid level meter 5 is installed inside the test box 3 to monitor the liquid level of the acid rain solution 6;

[0045] A temperature and humidity sensor is installed inside the test box 3 to detect the temperature and humidity inside the test box 3;

[0046] The bottom of the test box 3 is equipped with a sample table 7 which can be driven by a driving motor and can be moved up and down. The sample table 7 is a hollow structure made of anti-corrosion material. Figure 2 The specimen is suspended and tied in the middle by ropes, the upper surface angle of the specimen table 7 is variable, ranging from 30 to 90 degrees, and the lower side of the test table is connected to the bottom of the test box 3 through a support column;

[0047] A circulating fan 4 is installed in the test box 3 to change the wind speed according to the actual environment, with multiple adjustable gears to adjust the temperature and humidity in the test box;

[0048] An atomizing nozzle 9 is installed on the upper part of the test box 3, and the spraying method and flow rate of the atomizing nozzle 9 are adjustable;

[0049] A plurality of ultraviolet lamps 8 are installed in the test box 3, and the lampshades of the ultraviolet lamps 8 are anti-corrosion structures to adjust the temperature and humidity in the test box;

[0050] The acid rain solution storage tank 2 is provided with an acid rain solution 6, the outlet of the acid rain solution storage tank 2 is connected to the atomizing nozzle 9 through a spray pipe 17, and the spray pipe 17 is provided with a self-priming pump 1, and the inlet of the acid rain solution storage tank 2 is connected to the bottom of the test box 3 through a reflux pipe 18, and the reflux pipe 18 is provided with a filter 15 and an electric valve 16;

[0051] The circulating fan 4, ultraviolet lamp 8, self-priming pump 1, electric valve 16 and driving motor control signal are connected to the output signal end of the control device, and the liquid level meter 5 and temperature and humidity sensor are connected to the input signal end of the control device;

[0052] The test process of the experimental device is precisely controlled by a control device, which includes a first relay 11, a second relay 12, a third relay 13, a fourth relay 14, a control system 10 and a control box. The opening point of the first relay 11 is connected to the power supply end of the self-priming pump 1, and the coil of the first relay 11 is connected to the digital output port of the control system 10. The opening point of the second relay 12 is connected to the power supply end of the electric valve 16, and the coil of the second relay 12 is connected to the digital output port of the control system 10. The opening point of the third relay 13 is connected to the power supply end of the drive motor, and the coil of the third relay 13 is connected to the digital output port of the control system 10. The opening point of the fourth relay 14 is connected to the power supply end of the ultraviolet lamp 8, and the coil of the fourth relay 14 is connected to the digital output port of the control system 10. The first relay 11, the second relay 12, the third relay 13, the fourth relay 14 and the control system 10 are all arranged in the control box.

[0053] A method for simulating atmospheric corrosion in an acid rain environment comprises the following steps:

[0054] S1. Sample pretreatment: Cut the sample to be tested into the required size, polish it step by step with sandpaper, and degrease its surface. After drying, tie the sample to the sample table 7, adjust the angle of the sample table 7 to make it meet the spray angle of the sample when it is in service, adjust the spray mode and flow rate of the atomizing nozzle 9 to meet the service conditions of the sample, and put the prepared acid rain solution 6 into the test box and the acid rain solution storage tank 2, so that the acid rain solution 6 in the test box 3 reaches the set liquid level;

[0055] S2. Equipment parameter setting: according to the experimental plan requirements, set the temperature and humidity in the test box and the temperature of the acid rain solution 6, set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and post-spraying UV lamp irradiation time in one week immersion cycle;

[0056] S3, Experimental operation: The equipment power is turned on, the circulating fan 4 is turned on, the wind force is adjusted to the ambient wind force when the sample is in service, so that the gas in the experimental box is evenly distributed, the sample table 7 drive motor power is turned on, the sample table 7 is lowered to below the acid rain solution 6 liquid surface, and after being immersed in corrosion for a set time, the sample table 7 rises to above the acid rain solution 6 liquid surface, and the ultraviolet lamp 8 is turned on at the same time, and the ultraviolet lamp 8 is used to continuously irradiate the sample. After the ultraviolet lamp 8 irradiates for a set time, the self-priming pump 1 is turned on, and the self-priming pump 1 transports the acid rain solution 6 through the spray pipe 17 to the atomizing nozzle 9, and starts to spray the sample continuously. After the set time, the power of the self-priming pump 1 is cut off, and the ultraviolet lamp 8 is continued to irradiate the sample. After the irradiation reaches the set time, the power of the ultraviolet lamp 8 is cut off, the ultraviolet lamp 8 is turned off, and the power of the driving motor of the sample table 7 is turned on. The sample table 7 is lowered below the liquid surface of the acid rain solution 6 to prepare for the next weekly immersion cycle; the above description is the specific steps of one cycle of the experiment. In the experimental plan, the total time of one cycle is generally set to one hour. According to the specific experimental requirements, it can also be set to other durations. The total number of cycles of the general experiment is 24 / n to 360 / n cycles, where n is the total time of one cycle;

[0057] S4. Experimental maintenance: The device realizes daily replenishment of the acid rain solution 6 below the experimental box by spraying the acid rain solution 6. When the liquid level meter 5 in the experimental box 3 detects that the liquid level reaches the maximum value, the control device sends a control command to automatically open the electric valve 16, and the acid rain solution 6 flows back from the experimental box 3 to the acid rain solution storage tank 2 through the reflux pipe 18, and the impurities are filtered through the filter 15. When the liquid level returns to the set value, the control device closes the electric valve 16. When the acid rain spray simulation is not performed in the experiment, only the acidic atmospheric environment immersion experiment is performed, or the liquid level reaches the minimum value during normal use of the equipment, the solution in the experimental box needs to be manually replenished to ensure the normal progress of the experiment.

[0058] The following examples are implemented on the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following examples. The methods used in the following examples are conventional methods unless otherwise specified.

[0059] [Example 1]

[0060] See Figure 1 , which is a structural schematic diagram of the present invention. The present invention is a simulated acid rain environment atmospheric corrosion experimental device, comprising a test box 3, an acid rain solution storage tank 2, an atomizing nozzle 9, a circulating fan 4, an ultraviolet lamp 8, a liquid level meter 5, a temperature and humidity sensor, a driving motor, a filter 15, an electric valve 16, a self-priming pump 1 and a control device;

[0061] The bottom of the test box 3 is loaded with an acid rain solution 6, which is 0.01 mol / L NaHSO at 25°C. 3， Can be configured as needed according to the experimental environment;

[0062] A liquid level meter 5 is installed inside the test box 3 to monitor the liquid level of the acid rain solution 6;

[0063] A temperature and humidity sensor is installed inside the test box 3 to detect the temperature and humidity inside the test box 3;

[0064] The bottom of the test box 3 is equipped with a sample table 7 which can be driven by a driving motor and can be moved up and down. The sample table 7 is a hollow structure made of anti-corrosion material. Figure 2 The specimen is suspended and tied in the middle by ropes, the upper surface angle of the specimen table 7 is variable, ranging from 30 to 90 degrees, and the lower side of the test table is connected to the bottom of the test box 3 through a support column;

[0065] A circulating fan 4 is installed in the test box 3 to change the wind speed according to the actual environment, with multiple adjustable gears to adjust the temperature and humidity in the test box;

[0066] An atomizing nozzle 9 is installed on the upper part of the test box 3, and the spraying method and flow rate of the atomizing nozzle 9 are adjustable;

[0067] A plurality of ultraviolet lamps 8 are installed in the test box 3, and the lampshades of the ultraviolet lamps 8 are anti-corrosion structures to adjust the temperature and humidity in the test box;

[0068] The acid rain solution storage tank 2 is provided with an acid rain solution 6, the outlet of the acid rain solution storage tank 2 is connected to the atomizing nozzle 9 through a spray pipe 17, and the spray pipe 17 is provided with a self-priming pump 1, and the inlet of the acid rain solution storage tank 2 is connected to the bottom of the test box 3 through a reflux pipe 18, and the reflux pipe 18 is provided with a filter 15 and an electric valve 16;

[0069] The circulating fan 4, ultraviolet lamp 8, self-priming pump 1, electric valve 16 and driving motor control signal are connected to the output signal end of the control device, and the liquid level meter 5 and temperature and humidity sensor are connected to the input signal end of the control device;

[0070] The test process of the experimental device is precisely controlled by a control device, which includes a first relay 11, a second relay 12, a third relay 13, a fourth relay 14, a control system 10 and a control box. The opening point of the first relay 11 is connected to the power supply end of the self-priming pump 1, and the coil of the first relay 11 is connected to the digital output port of the control system 10. The opening point of the second relay 12 is connected to the power supply end of the electric valve 16, and the coil of the second relay 12 is connected to the digital output port of the control system 10. The opening point of the third relay 13 is connected to the power supply end of the drive motor, and the coil of the third relay 13 is connected to the digital output port of the control system 10. The opening point of the fourth relay 14 is connected to the power supply end of the ultraviolet lamp 8, and the coil of the fourth relay 14 is connected to the digital output port of the control system 10. The first relay 11, the second relay 12, the third relay 13, the fourth relay 14 and the control system 10 are all arranged in the control box.

[0071] A method for simulating atmospheric corrosion in an acid rain environment, wherein the test sample used is rail steel U75vh which has been in service in an acid rain environment for many years, and three parallel samples are set in each test cycle, including the following steps:

[0072] S1. Sample pretreatment: Use a high-speed saw to cut and cut the sample required for the experiment. The sample size is 45mm x 45mm x5mm. Each surface is polished step by step with sandpaper until it is bright. Use alkali solution to remove surface grease and use anhydrous ethanol and deionized water to rinse. After drying with a hair dryer, tie the sample horizontally to the sample table 7, adjust the angle of the sample table 7 to 70°, adjust the spray mode and flow rate of the atomizing nozzle 9, and put the prepared 0.01mol / LNaHSO3 acid rain solution 6 into the test box and the acid rain solution storage tank 2, so that the acid rain solution 6 in the test box 3 reaches the set liquid level;

[0073] S2. Equipment parameter setting: according to the experimental plan, set the temperature in the test box 3 to 45°C, the humidity to 70%RH, and the temperature of the acid rain solution 6 to 45°C. According to the experimental plan requirements, set the temperature and humidity in the test box and the temperature of the acid rain solution. Set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and UV lamp irradiation time after spraying in a weekly immersion cycle. Take 1h as a cycle, and perform corresponding control at the 0th minute, 12th minute, 28th minute and 44th minute of each cycle;

[0074] S3, Experimental operation: Turn on the power of the equipment, turn on the circulating fan 4, adjust the wind speed to the middle gear, make the gas in the experimental box evenly distributed, turn on the power of the sample table 7, and the sample table 7 is lowered to below the liquid surface of the acid rain solution 6. After immersion and corrosion for the 12th minute, the sample table 7 rises to above the liquid surface, and at the same time, turn on the ultraviolet lamp 8, and use the ultraviolet lamp 8 to continuously irradiate the sample. The ultraviolet lamp 8 irradiates for the 28th minute, turn on the self-priming pump 1, and the self-priming pump 1 transports the acid rain solution 6 to the atomizing nozzle 9 through the spray pipe 17, and starts to continuously spray the sample. The spraying lasts for the 44th minute, and the power of the self-priming pump 1 is cut off. The ultraviolet lamp 8 continues to continuously irradiate the sample for the 60th minute, and the power of the ultraviolet lamp 8 is cut off. The ultraviolet lamp 8 is turned off, and the power of the sample table 7 is turned on. The sample table 7 is lowered to below the liquid surface of the acid rain solution 6, and the next weekly immersion cycle is prepared; the total number of experimental cycles is 360h, and samples are taken and analyzed at the 24th, 72th, 144th, 240th, and 360th hours respectively;

[0075] S4. Experimental maintenance: The device realizes daily replenishment of the acid rain solution 6 below the test box 3 by spraying the acid rain solution 6. When the liquid level detected by the liquid level meter 5 reaches the maximum value, the control system 10 automatically opens the electric valve 16, and the acid rain solution 6 flows back from the test box 3 to the acid rain solution storage tank 2, and impurities are filtered through the filter 15. When the liquid level returns to the set value, the control system 10 closes the electric valve 16.

[0076] See Figure 3-7 In this embodiment, the macroscopic morphology of the samples before rust removal with different cycle numbers is presented under the accelerated corrosion test of atmospheric corrosion in a simulated acid rain environment. At 24 hours of corrosion, the surface is black. At 72 hours of corrosion, a large area of ​​yellow rust begins to appear. At 144 hours, the surface is basically covered with a rust layer. The rust layer is uneven and does not fall off. At 240 hours of corrosion, the color of the rust layer changes from yellow to reddish brown. At 360 hours, the color of the rust layer changes from reddish brown to black gray, indicating that the stability of the rust layer is gradually enhanced. The uneven rust layer caused by the spraying of the acid rain solution 6 can also be found on the surface of the sample; it is almost consistent with the corrosion morphology during actual service.

[0077] [Example 2]

[0078] The device in this embodiment is the same as that in embodiment 1;

[0079] A method for simulating atmospheric corrosion in an acid rain environment, wherein the test sample used is rail steel U75vh which has been in service in an acid rain environment for many years, and the method comprises the following steps:

[0080] S1. Sample pretreatment: Use a high-speed saw to cut and cut the sample required for the experiment. The sample size is 45mm x 45mm x5mm. Each surface is polished step by step with sandpaper until it is bright. Use alkali solution to remove surface grease and use anhydrous ethanol and deionized water to rinse. After drying with a hair dryer, tie the sample horizontally to the sample table 7, adjust the angle of the sample table 7 to 45°, adjust the spray mode and flow rate of the atomizing nozzle 9, and put the prepared 0.01mol / LNaNO3 acid rain solution 6 into the test box and the acid rain solution storage tank 2, so that the acid rain solution 6 in the test box 3 reaches the set liquid level;

[0081] S2. Equipment parameter setting: according to the experimental plan, set the temperature in the test box 3 to 45°C, the humidity to 70%RH, and the temperature of the acid rain solution 6 to 45°C, set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and post-spraying UV lamp irradiation time in one week immersion cycle, with 1h as one cycle, and perform corresponding control at the 0th minute, 12th minute, 28th minute and 36th minute of each cycle;

[0082] S3, Experimental operation: Turn on the power of the equipment, turn on the circulating fan 4, adjust the wind speed to the middle gear, make the gas in the experimental box evenly distributed, turn on the power of the driving motor of the sample table 7, and the sample table 7 is lowered to below the liquid surface of the acid rain solution 6. After immersion and corrosion for the 12th minute, the sample table 7 rises to above the liquid surface, and at the same time, turn on the ultraviolet lamp 8, and use the ultraviolet lamp 8 to continuously irradiate the sample. The ultraviolet lamp 8 irradiates for the 28th minute, turn on the self-priming pump 1, and the self-priming pump 1 transports the acid rain solution 6 to the atomizing nozzle 9 through the spray pipe 17, and starts to spray the sample continuously for the 36th minute, cut off the power of the self-priming pump 1, and continue to use the ultraviolet lamp 8 to continuously irradiate the sample for the 60th minute, cut off the power of the ultraviolet lamp 8, turn off the ultraviolet lamp 8, turn on the power of the sample table 7, and the sample table 7 is lowered to below the liquid surface of the acid rain solution 6, and prepare for the next weekly immersion cycle; the total number of experimental cycles is 360h, and samples are taken and analyzed at the 24th, 72th, 144th, 240th, and 360th hours respectively;

[0083] S4. Experimental maintenance: The device realizes daily replenishment of the acid rain solution 6 below the test box 3 by spraying the acid rain solution 6. When the liquid level detected by the liquid level meter 5 reaches the maximum value, the control system 10 automatically opens the electric valve 16, and the acid rain solution 6 flows back from the test box 3 to the acid rain solution storage tank 2, and impurities are filtered through the filter 15. When the liquid level returns to the set value, the control system 10 closes the electric valve 16.

[0084] See Figure 8-12 In this embodiment, the macroscopic morphology of the samples before rust removal with different cycle numbers is presented under the accelerated atmospheric corrosion test simulating an acid rain environment. The change law of the rust layer morphology is similar to that of Example 1, except that the spraying time in the cycle is reduced and the uniformity of the rust layer is increased.

[0085] [Example 3]

[0086] The device in this embodiment is the same as that in embodiment 1;

[0087] A method for simulating atmospheric corrosion in an acid rain environment, wherein the test sample used is rail steel R350lht which has been in service in an acid rain environment for many years, and the method comprises the following steps:

[0088] S1. Sample pretreatment: Use a high-speed saw to cut the sample required for the experiment. The sample size is 45mm x 45mm x5mm. Each surface is polished step by step with sandpaper until it is bright. Use alkali solution to remove surface grease and use anhydrous ethanol and deionized water to rinse. After drying with a hair dryer, tie the sample horizontally to the sample table 7, adjust the angle of the sample table 7 to 60°, adjust the spray mode and flow rate of the atomizing nozzle 9, and put the prepared 0.005mol / LNaHSO3+0.005mol / LNaNO3 acid rain solution 6 into the test box and the acid rain solution storage tank 2, so that the acid rain solution 6 in the test box 3 reaches the set liquid level;

[0089] S2. Equipment parameter setting: according to the experimental plan, set the temperature in the test box 3 to 45°C, the humidity to 70%RH, and the temperature of the acid rain solution 6 to 45°C, set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and post-spraying UV lamp irradiation time in one week immersion cycle, with 1h as one cycle, and perform corresponding control at the 0th minute, 10th minute, 25th minute and 50th minute of each cycle;

[0090] S3, Experimental operation: Turn on the power of the equipment, turn on the circulating fan 4, adjust the wind speed to the middle gear, make the gas in the experimental box evenly distributed, turn on the power of the driving motor of the sample table 7, and the sample table 7 is lowered to below the liquid surface of the acid rain solution 6. After immersion and corrosion for the 10th minute, the sample table 7 rises to above the liquid surface, and at the same time, turn on the ultraviolet lamp 8, and use the ultraviolet lamp 8 to continuously irradiate the sample. The ultraviolet lamp 8 irradiates for the 25th minute, turn on the self-priming pump 1, and the self-priming pump 1 transports the acid rain solution 6 to the atomizing nozzle 9 through the spray pipe 17, and starts to continuously spray the sample. The spraying lasts for the 50th minute, and the power of the self-priming pump 1 is cut off. The ultraviolet lamp 8 continues to continuously irradiate the sample. The irradiation lasts for the 60th minute, and the power of the ultraviolet lamp 8 is cut off. The ultraviolet lamp 8 is turned off, and the power of the sample table 7 is turned on. The sample table 7 is lowered to below the liquid surface of the acid rain solution 6, and the next weekly immersion cycle is prepared; the total number of experimental cycles is 360h, and samples are taken and analyzed at the 24th, 72th, 144th, 240th, and 360th hours respectively;

[0091] S4. Experimental maintenance: The device realizes daily replenishment of the acid rain solution 6 below the test box 3 by spraying the acid rain solution 6. When the liquid level detected by the liquid level meter 5 reaches the maximum value, the control system 10 automatically opens the electric valve 16, and the acid rain solution 6 flows back from the test box 3 to the acid rain solution storage tank 2, and impurities are filtered through the filter 15. When the liquid level returns to the set value, the control system 10 closes the electric valve 16.

[0092] See Figure 13-17 In this embodiment, the macroscopic morphology of the samples before rust removal at different cycle numbers is presented under the accelerated atmospheric corrosion test simulating an acid rain environment. Since NaNO3 is added to the acid rain solution, the sample corrosion is more severe under the combined action of NaNO3 and NaHSO3, and the spraying time in the cycle is increased. The change law of the rust layer morphology is quite different from that of Examples 1 and 2. The rust layer covers faster, the color of the rust layer changes faster, and the rust layer is more uneven.

Claims

1. A simulated acid rain environment atmospheric corrosion test device, characterized in that: It includes a test chamber, an acid rain solution storage tank, an atomizing nozzle, a circulating fan, an ultraviolet lamp, a liquid level meter, a temperature and humidity sensor, a drive motor, a filter, an electric valve, a self-priming pump and a control device; An acid rain solution is arranged at the bottom of the test box, a liquid level meter and a temperature and humidity sensor are arranged inside the test box to monitor the liquid level of the acid rain solution, a sample table that can move up and down is arranged at the bottom of the test box, a circulating fan is arranged in the test box, and the wind force of the circulating fan changes according to the environment, an atomizing nozzle is arranged above the test table at the top of the test box, and the mode and flow rate of atomizing spraying and splashing solution are adjusted according to needs, and an ultraviolet lamp is arranged in the test box; Acid rain solution is arranged in the acid rain solution storage tank, the outlet of the acid rain solution storage tank is connected to the atomizing nozzle through a spray pipe, and a self-priming pump is arranged on the spray pipe, and the inlet of the acid rain solution storage tank is connected to the bottom of the test box through a reflux pipe, and a filter and an electric valve are arranged on the reflux pipe; The circulating fan, ultraviolet lamp, self-priming pump, temperature and humidity sensor, electric valve and driving motor control signals are connected to the control device.

2. The simulated acid rain environment atmospheric corrosion test device according to claim 1 is characterized in that: The control device includes a first relay, a second relay, a third relay, a fourth relay, a control system and a control box. The opening point of the first relay is connected to the power supply terminal of the self-priming pump, the coil of the first relay is connected to the digital output port of the control system, the opening point of the second relay is connected to the power supply terminal of the electric valve, the coil of the second relay is connected to the digital output port of the control system, the opening point of the third relay is connected to the power supply terminal of the drive motor, the coil of the third relay is connected to the digital output port of the control system, the opening point of the fourth relay is connected to the power supply terminal of the ultraviolet lamp, the coil of the fourth relay is connected to the digital output port of the control system, and the first relay, the second relay, the third relay, the fourth relay and the control system are all arranged in the control box.

3. The simulated acid rain environment atmospheric corrosion test device according to claim 1 is characterized in that: The acid rain solution is 0.001-0.02 mol / LNaHSO3, 0.001-0.02 mol / LNaNO3 or (0.001-0.02) mol / LNaHSO3+(0.001-0.02) mol / LNaNO3 at 25°C.

4. The simulated acid rain environment atmospheric corrosion test device according to claim 1, characterized in that: The sample table is a hollow structure, with the sample tied up in the middle by ropes, the angle of the upper surface of the sample table varies from 30 to 90 degrees, and the lower part of the sample table is connected to the bottom of the test box by a support.

5. The simulated acid rain environment atmospheric corrosion test device according to claim 1, characterized in that: An anti-corrosion lampshade is arranged outside the ultraviolet lamp.

6. The experimental method of the simulated acid rain environment atmospheric corrosion experimental device according to any one of claims 1 to 5, characterized in that: The steps include: S1. Sample pretreatment: Cut the sample to be tested into the required size, polish it step by step with sandpaper, and degrease its surface. After drying, tie the sample to the sample table, adjust the angle of the sample table to make it consistent with the spray angle of the sample during service, adjust the spray mode and flow rate of the atomizing nozzle to meet the service conditions of the sample, and put the prepared acid rain solution into the test box and the acid rain solution storage tank so that the acid rain solution in the test box reaches the set liquid level; S2. Equipment parameter setting: according to the requirements of the experimental plan, set the temperature and humidity in the test box and the temperature of the acid rain solution, set the sample immersion corrosion time, immersion corrosion UV lamp irradiation time, atomization nozzle spraying time and post-spraying UV lamp irradiation time in a weekly immersion cycle; S3, Experimental operation: The equipment power is turned on, the circulating fan is turned on, the wind force is adjusted to the ambient wind force when the sample is in service, the sample table drive motor power is turned on, the sample table is lowered to below the acid rain solution surface, and after being immersed and corroded for a set time, the sample table rises to above the acid rain solution surface, and the ultraviolet lamp is turned on at the same time. After continuous irradiation for a set time, the self-priming pump is turned on. The self-priming pump transports the acid rain solution to the atomizing nozzle through the spray pipe, and starts to spray the sample continuously. After spraying for a set time, the self-priming pump power is cut off. After the ultraviolet lamp irradiates for the required set time, the ultraviolet lamp power is cut off, the ultraviolet lamp is turned off, and the sample table drive motor power is turned on. The sample table is lowered below the acid rain solution surface, and is ready for the next weekly immersion cycle; S4. Experimental maintenance: When the liquid level meter in the test chamber detects that the liquid level reaches the maximum value, the control device sends a control command to automatically open the electric valve, and the acid rain solution flows back from the test chamber to the acid rain solution storage tank through the reflux pipe, and the impurities are filtered out by the filter. When the liquid level returns to the set value, the control device closes the electric valve. When the acid rain spray simulation is not carried out in the experiment, and only the acidic atmospheric environment immersion experiment is carried out, or when the equipment is used normally and the liquid level reaches the minimum value, the solution in the test chamber needs to be replenished manually.

7. A simulated acid rain environment atmospheric corrosion test method according to claim 6, characterized in that: The number of immersion cycles is 24 / n to 360 / n cycles, where n is the total time of one cycle.

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