A strong magnetic field-high temperature and high pressure water coupling environment material corrosion experiment device and method

Abstract

The application discloses a kind of strong magnetic field-high temperature high pressure water coupling environment material corrosion experimental device and method, including pressure water generation device, pressure water circulation loop, experimental tube section, strong magnetic field generation device and control and data acquisition system.The application can realize the corrosion experiment of material in 10T order magnetic field environment, be favorable to accurately study the influence of 10T order strong magnetic field environment on the corrosion effect of material, and provide reference for the design of fusion reactor.Experiment tube section outside is coated with heat insulating material, can avoid the influence of high temperature environment on the superconducting material coil of strong magnetic field generation device.The application is suitable for various metal materials and non-metallic materials, by setting temperature rising branch and experimental branch, shorten the temperature rising time of material component used for experiment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fusion reactor structural and functional material corrosion research, and particularly relates to a strong magnetic field-high temperature and high pressure water coupling environment material corrosion experiment device and method. BACKGROUND

[0002] Achieving controlled utilization of nuclear fusion energy has great significance for solving the energy problem of human society. Fusion reactors will be used to achieve controlled utilization of nuclear fusion energy, high temperature plasma is confined by strong magnetic field, and heat is transported to the outside of the reactor by the water cooling system of the cladding structure, and then power generation is realized by the generator set after heat exchange. The pipes of the fusion reactor cladding water cooling system are usually made of low activation steel or stainless steel as the structural material, and high temperature and high pressure water (about 15 MPa, 300 DEG C) flowing at high speed as the cooling medium. The inner wall of the pipe will be corroded in the high temperature and high pressure water environment, on the one hand, the corrosion will damage the inner wall of the pipe, affect the service life of the water cooling system, on the other hand, the corrosion products produced by the corrosion will enter the flowing high temperature and high pressure water and migrate with it, and will generate radioactive activated corrosion products by interacting with the high energy neutrons generated by the fusion reaction, which will pose a threat to personnel and environmental safety. In the current scheme, the future fusion reactor can generate a strong magnetic field of up to 10 T order, which is used to control the high temperature plasma. In addition to the high temperature plasma, the cladding of the fusion reactor and the water cooling system included therein are also in a strong magnetic field environment. Accordingly, the corrosion process of the cooling system pipe will also be carried out in the strong magnetic field environment. According to the research results in other fields, the magnetic field environment may promote or inhibit the corrosion process of the material, but the conclusion is not clear. Therefore, it is necessary to study the influence of 10 T order strong magnetic field environment on the corrosion effect of the material. Due to the lack of strong magnetic field experimental conditions, the research on the corrosion of the material in the 10 T order magnetic field environment is very scarce, especially the research on the corrosion of the material in the coupling environment of high temperature and high pressure water and 10 T order strong magnetic field. 10 T strong magnetic field needs to be generated by superconducting coil in extremely low temperature environment, and the high temperature experiment environment of high temperature and high pressure water will affect the operation of the superconducting coil. SUMMARY

[0003] In order to solve the above technical problems, research the corrosion of the material in the coupling environment of high temperature and high pressure water and 10 T order strong magnetic field, and further clarify the influence of 10 T order strong magnetic field environment on the corrosion effect of the material, the present application provides a strong magnetic field-high temperature and high pressure water coupling environment material corrosion experiment device and method, which realizes the corrosion experiment of the material in the 10 T order magnetic field environment, and is beneficial to accurately research the influence of 10 T order strong magnetic field environment on the corrosion effect of the material, and provides a reference for the design of fusion reactor. The present application can be used for various metal materials and non-metal materials, and the temperature rising and falling branch and the experiment branch are set to shorten the temperature rising and falling time of the material components used for experiment.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A corrosion testing apparatus for materials in a strong magnetic field-high temperature and high pressure water coupled environment includes a pressurized water generating device, a pressurized water circulation loop, an experimental tube section, a strong magnetic field generating device, and a control and data acquisition system. The experimental tube section is covered with heat-insulating material and inserted into the cylindrical space of the strong magnetic field generating device. The control and data acquisition system is connected to the pressurized water generating device and the strong magnetic field generating device. The high temperature and high pressure water generated by the pressurized water generating device enters the pressurized water circulation loop and further enters the experimental tube section, where corrosion occurs in the high temperature and high pressure water environment. Subsequently, the high temperature and high pressure water returns sequentially to the pressurized water circulation loop and the pressurized water generating device, realizing the circulation of high temperature and high pressure water. The data acquisition system is connected to a pressure gauge and a flow meter via a data cable or wireless signal to record readings. The data acquisition system is also connected to a thermocouple via a data cable or wireless signal to control the heating power.

[0006] This invention also provides an experimental method for a material corrosion test apparatus in a strong magnetic field-high temperature and high pressure water coupled environment, comprising the following steps:

[0007] Step S1: Determine the material properties and classify them into two categories: metal structural materials that can withstand high temperature and high pressure water, and other materials.

[0008] Step S2: Connect the heating and cooling branch and the experimental branch of the pressurized water circulation circuit to perform a sealing test on the experimental device;

[0009] Step S3: Add the experimental solution to the high-temperature and high-pressure water generating device, turn on the high-temperature pump, and fill the pressure water circulation loop with the experimental solution; close the experimental branch, turn on the heating module of the pressure water generating device, and the high-temperature and high-pressure water generating device heats up.

[0010] Step S4: When the pressure and temperature of the experimental solution at the experimental tube section reach the predetermined temperature and pressure, turn on the strong magnetic field generating device, and the magnetic field strength will increase from 0. After the magnetic field strength reaches the required magnetic field strength for the experiment, open the experimental branch of the pressure water circulation loop and close the heating and cooling branch; when the readings of one thermocouple and one pressure gauge in the experimental branch reach the predetermined temperature and pressure that the experimental material can withstand, the corrosion experiment begins; the control and data acquisition system maintains a constant pressure and temperature of the experimental solution by adjusting the power of the heating module.

[0011] Step S5: After the pressure and temperature of the experimental solution have been kept constant for a period of time, open the heating and cooling branch of the pressure water circulation loop, close the experimental branch, open the pressure reducing valve of the experimental branch, and when the pressure and temperature of the experimental solution in the experimental branch are the same as those of the outside environment, drain the remaining experimental solution in the experimental branch, disassemble the experimental pipe section, and the corrosion experiment ends.

[0012] Step S6: The control and data acquisition system reduces the temperature of the pressure water generating device by adjusting the power of the heating module; when the pressure and temperature of the experimental solution in the temperature rising and falling branch of the pressure water circulation loop are the same as the outside, the high-temperature pump is turned off;

[0013] Step S7: The tubular sample is directly taken out from the experimental tube segment, the heat insulation material is removed, and after being sufficiently dried in a vacuum drying box, the mass is accurately measured to 0.0001 g, the mass change before and after the corrosion experiment is calculated, and the sample pipeline is cut into two pieces of the same size and shape along the axis direction to expose the inner wall of the pipeline;

[0014] Step S8: The sample is analyzed.

[0015] The beneficial effects of the present application are:

[0016] 1. The present application realizes the corrosion experiment of materials in a 10T order magnetic field environment, which is conducive to accurately studying the influence of the 10T order strong magnetic field environment on the corrosion effect of materials. The present application provides experimental conditions for evaluating the corrosion of materials under strong magnetic field conditions, especially under the strong magnetic field conditions of a fusion reactor, and provides a reference for the design of a fusion reactor.

[0017] 2. The experimental tube segment is wrapped with heat insulation material on the outside, which can avoid the influence of the high-temperature environment on the superconducting material coil of the strong magnetic field generating device.

[0018] 3. The experimental tube segment directly made of metal structural materials that can withstand high-temperature and high-pressure water can accurately evaluate the corrosion effect of the pipeline made of metal materials under the use scenario of flowing high-temperature and high-pressure water.

[0019] 4. In addition to metal structural materials that can withstand high-temperature and high-pressure water, other materials, such as non-metallic material coatings, can also be used in the strong magnetic field environment high-temperature and high-pressure water corrosion experiment using the present device.

[0020] 5. The pressure water circulation loop is divided into a temperature rising and falling branch and an experimental branch, which can keep the experimental branch at room temperature during the waiting period for the pressure water to rise in temperature, and then connect the experimental branch when the temperature and pressure of the experimental solution in the pressure water generating device reach 20MPa and 400℃, so as to realize the rapid reaching of the temperature and pressure of the pressure water passing through the experimental branch to 20MPa and 400℃, and then start the corrosion time calculation. After the experiment, the pressure water in the experimental branch is rapidly released by using a pressure reducing valve, which can minimize the interference of the temperature rising and falling time on the corrosion time calculation. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a schematic view of a strong magnetic field-high temperature and high pressure water coupling environment material corrosion experiment device of the present application;

[0022] The attached diagram is labeled as follows: 1. Pressure water generating device; 2. Pressure water circulation loop; 3. Experimental pipe section; 4. Strong magnetic field generating device; 5. Control and data acquisition system; V1-V7. Valve 1-V7; G. High-temperature pump; P1-P3. Pressure gauge 1-P3; T1-T4. Thermocouple 1-T4; F1-F2. Flow meter 1-Flow meter 2; FL1. Filter 1; FL2. Filter 2; PRV. Pressure reducing valve; E1-E3. Rupture valve 1-Rupture valve 3. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] like Figure 1 As shown, the present invention provides a material corrosion experimental apparatus in a strong magnetic field-high temperature and high pressure water coupled environment, comprising a pressure water generating device 1, a pressure water circulation loop 2, an experimental pipe section 3, a strong magnetic field generating device 4, and a control and data acquisition system 5. The experimental pipe section 3 is covered with heat-insulating material and inserted into the cylindrical space of the strong magnetic field generating device 4. The control and data acquisition system 5 is connected to the pressure water generating device 1 and the strong magnetic field generating device 4. The high temperature and high pressure water generated by the pressure water generating device 1 enters the pressure water circulation loop 2 and further enters the experimental pipe section 3, where corrosion occurs in the high temperature and high pressure water environment. Subsequently, the high temperature and high pressure water returns sequentially to the pressure water circulation loop 2 and the pressure water generating device 1, achieving the circulation of high temperature and high pressure water. The data acquisition system 5 is connected to the first pressure gauge P1, the second pressure gauge P2, the third pressure gauge P3, the first flow meter F1, and the second flow meter F2 via data cables or wireless signals to record readings. The data acquisition system 5 is connected to the first thermocouple T1, the second thermocouple T2, the third thermocouple T3, and the fourth thermocouple T4 via data cable or wireless signal to control the heating power.

[0025] The pressure water generating device 1 is equipped with a first pressure gauge P1, a first thermocouple T1, and a first burst valve E1; the pressure water circulation loop 2 is equipped with a first valve V1-a seventh valve V7, a high-temperature pump G, a second pressure gauge P2, a third pressure gauge P3, a second thermocouple T2, a third thermocouple T3, a first flow meter F1, a second flow meter F2, a first filter FL1, a second filter FL2, a second burst valve E2, a third burst valve E3, and a pressure reducing valve PRV; the experimental pipe section 3 is equipped with a fourth thermocouple T4.

[0026] The pressure water generating device 1 comprises a pressure vessel, a heating module, and can generate high-temperature and high-pressure water with a maximum pressure of 20 MPa and a temperature of 400 DEG C by heating the experimental solution.

[0027] The experimental solution refers to a water solution prepared according to the needs of experimenters, containing one or more solutes, having a specific pH value, and having a specific oxygen content.

[0028] The strong magnetic field generating device 4 comprises a superconducting coil, a cooling system, a Tesla meter or a Gauss meter. The superconducting coil is made of superconducting wire and is cooled by liquid helium. The superconducting coil encloses a cylindrical space with a diameter of 100 mm and a height of 200 mm. After the superconducting coil is energized, a 15T magnetic field parallel to the cylindrical axis can be generated in the cylindrical space by adjusting the current intensity, and the Tesla meter or the Gauss meter can measure the magnetic field intensity in the cylindrical space.

[0029] The pressure water circulation loop 2 comprises a high-temperature pump G, a second thermocouple T2, a third thermocouple T3, a second pressure gauge P2, a third pressure gauge P3, a second pressure relief valve E2, a third pressure relief valve E3, and a pipeline for connecting the pressure water generating device 2 and the experimental pipe section 3, for driving the high-temperature and high-pressure water to circulate continuously between the pressure water generating device 1 and the experimental pipe section 3, controlling the flow rate of the circulating high-temperature and high-pressure water, and timely relieving pressure when the pressure of the experimental device exceeds a safety threshold to ensure the safety of personnel and the device. In the pressure water circulation loop 2, there are two branches, namely a temperature rising and falling branch and an experimental branch. The temperature rising and falling branch comprises a second valve V2, a third valve V3 and a pipeline therebetween. The experimental branch comprises a fifth valve V5, a sixth valve V6, a seventh valve V7, a second flow meter F2, a third thermocouple T3, a third pressure gauge P3, a pressure relief valve PRV, a third burst valve E3, a first filter FL1, a second filter FL2 and a pipeline connecting the foregoing components. The pipeline of the pressure water circulation loop 2 is covered with heat insulation material, and the inner diameter of the pipeline is 15 mm.

[0030] The control and data acquisition system 5 is connected with the pressure water generating device 1, the strong magnetic field generating device 4, and the first pressure gauge P1 to the third pressure gauge P3, the first thermocouple T1 to the fourth thermocouple T4, the first flow meter F1 and the second flow meter F2, can adjust the power of the heating module in the pressure water generating device 1 and the current intensity in the superconducting coil of the strong magnetic field generating device 4, can record the readings of the first pressure gauge P1 to the third pressure gauge P3, the first thermocouple T1 to the fourth thermocouple T4, the first flow meter F1, the second flow meter F2 and the Tesla meter or the Gauss meter of the strong magnetic field generating device 4 in real time, and can record the time corresponding to the generation of the readings.

[0031] The application also provides an experimental method based on the strong magnetic field-high temperature and high pressure water coupling environment material corrosion experimental device.

[0032] Step S1: Determine the material properties, and divide into two categories: metal structural materials that can withstand high temperature and high pressure water, and other materials. The metal structural material that can withstand high temperature and high pressure water is made into a tubular shape with a length of 150 mm, an inner diameter of 15 mm, and an outer diameter of 25 mm, called "tubular sample", accurately measure the mass to 0.0001 g, the outside is coated with thermal insulation material, as an experimental tube section, connected with the experimental branch of the pressure water circulation loop 2; other materials are made into 8 pieces of 10 mm x 10 mm x 2 mm, called "sheet sample", accurately measure the mass to 0.0001 g, put into a hastelloy tube with an inner diameter of 150 mm, an inner diameter of 15 mm, and an outer diameter of 25 mm, the samples are separated by ceramic gaskets, and the samples and the hastelloy tube are separated by ceramic gaskets; The installation direction of the ceramic gasket should not hinder the flow of pressure water, and the outside of the hastelloy tube is coated with thermal insulation material; The hastelloy tube together with the internally installed samples and ceramic gaskets is connected to the experimental tube section 3 and the experimental branch of the pressure water circulation loop 2.

[0033] Step S2: Turn on the temperature rising and falling branch and the experimental branch of the pressure water circulation loop 2, and test the sealing of the experimental device.

[0034] Step S3: In the pressure water generating device 1, add the experimental solution, start the high temperature pump G, and fill the pressure water circulation loop 2 with the experimental solution. Close the experimental branch, start the heating module of the pressure water generating device 1, and heat the pressure water generating device 1.

[0035] Step S4: When the pressure and temperature of the experimental solution measured at the experimental tube section 3 reach the predetermined temperature and pressure, start the strong magnetic field generating device 4, and increase the magnetic field strength from 0. When the magnetic field strength reaches 10T, start the experimental branch of the pressure water circulation loop 2, and close the temperature rising and falling branch. When the readings of the 3rd thermocouple T3 and the 3rd pressure gauge P3 of the experimental branch reach the pressure and temperature that the experimental material can withstand, the corrosion experiment begins. The control and data acquisition system 5 maintains the pressure and temperature of the experimental solution constant by adjusting the power of the heating module. The experimental personnel can adjust the high temperature pump G to make the 2nd flow meter F2 reach a specific reading, and set the time for maintaining the pressure and temperature of the ionized water constant as needed.

[0036] Step S5: After the time for maintaining the pressure and temperature of the experimental solution constant ends, start the temperature rising and falling branch of the pressure water circulation loop 2, close the experimental branch, start the pressure reducing valve PRV of the experimental branch, and when the pressure and temperature of the experimental solution in the experimental branch are the same as those outside, discharge the remaining experimental solution in the experimental branch, and disassemble the experimental tube section 3. The corrosion experiment is completed.

[0037] Step S6: The control and data acquisition system 5 reduces the temperature of the pressure water generating device 1 by adjusting the power of the heating module. When the pressure and temperature of the experimental solution in the temperature rising and falling branch of the pressure water circulating loop 2 and the pressure water generating device 1 are the same as the outside world, the high-temperature pump G is turned off, and the experiment is completed.

[0038] Step S7: The tubular sample is directly taken out from the experimental tube segment 3, the heat insulation material is removed, and after being fully dried in a vacuum drying box, the mass is accurately measured to 0.0001 g, the mass change before and after the corrosion experiment is calculated, and the sample pipe is cut into two pieces of the same size and shape along the axis direction to expose the inner wall of the pipe. For the sheet sample, first take out the hastelloy pipe from the experimental tube segment, then take out the sheet sample from the hastelloy pipe, and after being fully dried in a vacuum drying box, the mass is accurately measured to 0.0001 g, and the mass change before and after the corrosion experiment is calculated.

[0039] Step S8: The sample is analyzed, including but not limited to: observing the macroscopic morphology of the tubular sample or sheet sample after corrosion, including color, distribution of color, distribution of non-uniform corrosion area. The surface micro-morphology of the sample is observed using a scanning electron microscope, the elemental composition and distribution of the sample surface are analyzed using an energy dispersive spectrometer, and the phase of the sample is analyzed using an X-ray diffractometer. The experimental solution sample in the pressure water generating device is extracted, the conductivity is measured, and the dissolved elemental composition and content in the experimental solution are analyzed using an inductively coupled atomic emission spectrometer. The corrosion product particles in the filter are collected, the phase is analyzed using an X-ray diffractometer, and the elemental composition and valence state are analyzed using an X-ray photoelectron spectrometer.

[0040] Preferably, the personnel using the experimental device can set the temperature of the experimental solution to be higher than room temperature, any temperature not exceeding 400°C, and the pressure to be higher than atmospheric pressure, any pressure not exceeding 20 MPa, according to the needs of the experiment.

[0041] Embodiment:

[0042] Taking the 15 MPa, 300°C deionized water corrosion experiment of 316 stainless steel tubular sample with magnetic field strength 15 T, corrosion time 2 h, and flow rate 0.1 m / s as an example. First, determine the performance of 316 stainless steel, which is a metal structural material that can withstand high-temperature and high-pressure water. A tubular sample with a length of 150 mm, an inner diameter of 15 mm, and an outer diameter of 25 mm is made of 316 stainless steel, the mass is accurately measured to 0.0001 g, and is used as the experimental tube segment 3. The experimental device is sealed by opening the 1st valve V1-6th valve V6 and closing the 7th valve V7.

[0043] In the pressure water generating device 1, room temperature deionized water is added, and the high temperature pump G is opened. After the readings of the first flow meter F1 and the second flow meter F2 are stable, the fifth valve V5 and the sixth valve V6 are closed, the heating module of the pressure water generating device 1 is opened, and the pressure water generating device 1 is warmed up. When the readings of the first pressure gauge P1 and the first thermocouple T1 are 15 MPa and 300℃, the strong magnetic field generating device 4 is opened, and the magnetic field strength starts to increase from 0. When the magnetic field strength reaches 15T, the fifth valve V5 and the sixth valve V6 are opened, and the second valve V2 and the third valve V3 are closed. When the readings of the third pressure gauge P3 and the fourth thermocouple T4 are 15 MPa and 300℃, the corrosion experiment starts. The control system 5 adjusts the power of the heating module to keep the deionized water pressure and temperature constant. The high temperature pump G is adjusted to make the reading of the second flow meter F2 reach 0.1 m / s, and the deionized water pressure and temperature are kept constant for 2 hours. The second valve V2 and the third valve V3 are opened, the fifth valve V5 and the sixth valve V6 are closed, the pressure reducing valve PRV is opened, the readings of the third pressure gauge P3 and the fourth thermocouple T4 are the same as the outside, the seventh valve V7 is opened, the remaining deionized water in the experimental branch is discharged, and the experimental pipe section 3 is removed. The corrosion experiment is completed.

[0044] The control and data acquisition system 5 adjusts the power of the heating module to lower the temperature of the pressure water generating device 1. When the readings of the second pressure gauge P2, the second thermocouple T2 and the temperature reach room temperature, the high temperature pump G is closed.

[0045] The tubular sample of 316 stainless steel is directly taken out from the experimental pipe section 3, dried in a vacuum drying box, and then accurately measured for mass with an accuracy of 0.0001 g. The mass change before and after the corrosion experiment is calculated, and the sample pipe is cut into two pieces of the same size and shape along the axis to expose the inner wall of the pipe. The macroscopic morphology of the corroded tubular sample is observed, including color, color distribution, and non-uniform corrosion area distribution. The surface microstructure of the sample is observed using a scanning electron microscope, the elemental composition and distribution of the sample surface are analyzed using an energy dispersive spectrometer, and the phase of the sample is analyzed using an X-ray diffractometer. The deionized water sample in the pressure water generating device 1 is extracted, the conductivity is measured, and the dissolved elemental composition and content in the deionized water are analyzed using an inductively coupled atomic emission spectrometer. The corrosion product particles in the first filter FL1 and the second filter FL2 are collected, and the phase is analyzed using an X-ray diffractometer, and the elemental composition and valence state are analyzed using an X-ray photoelectron spectrometer.

[0046] This embodiment carries out an experiment of 15 MPa, 300℃ deionized water corrosion of 316 stainless steel tubular sample in a 15T strong magnetic field environment for 2 hours at a flow rate of 0.1 m / s, which is beneficial to accurately evaluate the influence of 15T strong magnetic field environment similar to fusion reactor on the corrosion effect of 316 stainless steel in the working condition of fusion reactor cooling system, and provides a reference for the design of fusion reactor.

[0047] In the description of the application, it should be understood that the number, arrangement or positional relationship of each component shown in the drawings is only for the convenience of describing the application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific number, a specific arrangement, a specific structure and operation in a specific position, and therefore cannot be understood as a limitation on the application. In the present application, unless otherwise specified and limited, the terms "mounting", "connection", "connection", and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. Although the specific implementation methods of the present application are described above, those skilled in the art should understand that these are only illustrative, and various changes or modifications can be made to these embodiments without departing from the principles and implementation of the present application, therefore, the protection scope of the present application is defined by the appended claims.

Claims

1. An experimental method for a material corrosion experimental apparatus in a strong magnetic field-high temperature and high pressure water coupled environment, characterized in that, The experimental apparatus for material corrosion in a coupled environment of strong magnetic field and high-temperature, high-pressure water includes a pressurized water generating device, a pressurized water circulation loop, an experimental pipe section, a strong magnetic field generating device, and a control and data acquisition system. The experimental pipe section is covered with thermal insulation material and inserted into the cylindrical space of the strong magnetic field generating device. The control and data acquisition system is connected to both the pressurized water generating device and the strong magnetic field generating device. The high-temperature, high-pressure water generated by the pressurized water generating device enters the pressurized water circulation loop and further enters the experimental pipe section, where corrosion occurs in the high-temperature, high-pressure water environment. Subsequently, the high-temperature, high-pressure water returns sequentially to the pressurized water circulation loop and the pressurized water generating device, thus achieving the circulation of the high-temperature, high-pressure water. The control and data acquisition system is connected to a pressure gauge and a flow meter via a data cable or wireless signal to record readings. The data acquisition system is connected to a thermocouple via a data cable or wireless signal to control the heating power. The experimental method includes the following steps: Step S1: Determine the material properties and classify them into two categories: metallic structural materials that can withstand high temperature and high pressure water, and other materials; Step S2: Connect the heating and cooling branch and the experimental branch of the pressurized water circulation circuit to perform a sealing test on the experimental device; Step S3: Add the experimental solution to the high-temperature and high-pressure water generating device, turn on the high-temperature pump, and fill the pressure water circulation loop with the experimental solution; close the experimental branch, turn on the heating module of the pressure water generating device, and the high-temperature and high-pressure water generating device heats up. Step S4: When the pressure and temperature of the experimental solution at the experimental tube section reach the predetermined temperature and pressure, turn on the strong magnetic field generating device, and the magnetic field strength increases from 0; after the magnetic field strength reaches the required magnetic field strength for the experiment, turn on the experimental branch of the pressure water circulation loop and turn off the heating and cooling branch; when the readings of one thermocouple and one pressure gauge in the experimental branch reach the predetermined temperature and pressure that the experimental material can withstand, the corrosion experiment begins; the control and data acquisition system maintains a constant pressure and temperature of the experimental solution by adjusting the power of the heating module. Step S5: After the pressure and temperature of the experimental solution have been kept constant for a period of time, open the heating and cooling branch of the pressure water circulation loop, close the experimental branch, open the pressure reducing valve of the experimental branch, and when the pressure and temperature of the experimental solution in the experimental branch are the same as those of the outside environment, drain the remaining experimental solution in the experimental branch, disassemble the experimental pipe section, and the corrosion experiment ends. Step S6: The control and data acquisition system adjusts the power of the heating module to lower the temperature of the pressure water generating device; when the pressure and temperature of the experimental solution in the heating and cooling branches of the pressure water generating device and the pressure water circulation loop are the same as those of the outside environment, the high-temperature pump is turned off. Step S7: The tubular sample is taken directly from the experimental tube section, the insulation material is removed, and after being fully dried in a vacuum drying oven, the mass is accurately measured to 0.0001g. The mass change before and after the corrosion experiment is calculated. Then, the sample tube is cut into two pieces of the same size and shape along the axial direction to expose the inner wall of the tube. Step S8: Analyze the sample.

2. The experimental method according to claim 1, characterized in that, The pressure water generating device includes a pressure vessel and a heating module, which heats the experimental solution and can generate high-temperature and high-pressure water at a maximum pressure of 20 MPa and a temperature of 400°C.

3. The experimental method according to claim 1, characterized in that, The strong magnetic field generating device includes a superconducting coil, a cooling system, and a teslameter or gaussmeter. The superconducting coil is made of superconducting wire wound together and cooled by liquid helium. The superconducting coil encloses a cylindrical space with a diameter of 100 mm and a height of 200 mm. After the superconducting coil is energized, a 15T magnetic field environment parallel to the cylindrical axis can be generated in the cylindrical space by adjusting the current intensity. The teslameter or gaussmeter is used to measure the magnetic field intensity in the cylindrical space.

4. The experimental method according to claim 1, characterized in that, The pressure water circulation loop includes a high-temperature pump G, multiple thermocouples T2, multiple pressure gauges, multiple pressure relief valves, and pipes for connecting the pressure water generating device and the experimental pipe section. It is used to drive high-temperature and high-pressure water to circulate continuously between the pressure water generating device and the experimental pipe section, control the flow rate of the circulating high-temperature and high-pressure water, and release pressure in a timely manner when the pressure of the experimental device exceeds the safety threshold to ensure the safety of personnel and equipment.

5. The experimental method according to claim 1, characterized in that, The pressurized water circulation loop includes an experimental branch and a heating / cooling branch. The experimental pipe section is connected to the experimental branch and inserted into the cylindrical space enclosed by the superconducting coil of the strong magnetic field generating device.

6. The experimental method according to claim 1, characterized in that, The control and data acquisition system is connected to the pressurized water generating device, the strong magnetic field generating device, and multiple pressure gauges, multiple thermocouples, and multiple flow meters. It can adjust the power of the heating module in the pressurized water generating device and the current intensity in the superconducting coil of the strong magnetic field generating device, and record the readings of the multiple pressure gauges, multiple thermocouples, multiple flow meters, and the Tesla or Gauss meter of the strong magnetic field generating device in real time, and record the time when the corresponding readings are generated.

7. The experimental method according to claim 1, characterized in that, In step 1, the metal structural material that can withstand high temperature and high pressure water should ensure that it can withstand the predetermined temperature and pressure of 20MPa and 400℃, and the experimental solution can be deionized water. In step 1, a tubular sample, 150mm long, 15mm inner diameter, and 25mm outer diameter, made of a metal structural material capable of withstanding high-temperature and high-pressure water, is used. Its mass is accurately measured to 0.0001g. The sample is covered with thermal insulation material and serves as the experimental tube section, connected to the experimental branch of the pressurized water circulation loop. Other materials are used to make eight 10mm×10mm×2mm sheets, called "sheet samples," with their mass accurately measured to 0.0001g. These sheets are placed inside a Hastelloy tube with an inner diameter of 150mm, an inner diameter of 15mm, and an outer diameter of 25mm. Ceramic gaskets separate the samples from each other and from the Hastelloy tube. The ceramic gaskets should not obstruct the flow of pressurized water. The Hastelloy tube is covered with thermal insulation material. The Hastelloy tube, along with the internally installed samples and ceramic gaskets, serves as the experimental tube section connected to the experimental branch of the pressurized water circulation loop.

8. The experimental method according to claim 7, characterized in that, In step 7, for sheet-like samples, the Hastelloy tube is first removed from the experimental tube section, and then the sheet-like sample is removed from the Hastelloy tube. After being thoroughly dried in a vacuum drying oven, the mass is accurately measured to an accuracy of 0.0001g, and the mass change before and after the corrosion experiment is calculated.

9. The experimental method according to claim 1, characterized in that, Step 8 includes: observing the macroscopic morphology of the corroded tubular or sheet-like sample, including color, color distribution, and distribution of non-uniform corrosion areas; observing the microscopic morphology of the sample surface using a scanning electron microscope, analyzing the elemental composition and distribution of the sample surface using an energy dispersive spectroscopy (EDS) spectrometer, and analyzing the phase composition using an X-ray diffractometer; extracting the experimental solution sample from the pressurized water generating device, measuring its conductivity, and analyzing the dissolved elemental composition and content in the experimental solution using an inductively coupled atomic emission spectrometer (ICAES); collecting corrosion product particles from the filter, analyzing the phase composition using an X-ray diffractometer, and analyzing the elemental composition and valence state using an X-ray photoelectron spectroscopy (XPSS).

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