Rapid evaluation method for material corrosion rate and influence factors in high-level radioactive waste geological disposal environment

Abstract

The invention relates to the field of metal corrosion behavior monitoring and characterization, in particular to a rapid evaluation method for a material corrosion rate and influence factors in a high-level radioactive waste geological disposal environment. According to the method, two indexes are obtained based on electrochemical impedance spectroscopy measurement and relaxation time distribution analysis, namely an impedance modulus value Z0.01 Hz value corresponding to 0.01 Hz and a time constant log (tau / s) value corresponding to a dissolved oxygen reduction reaction. The Z0.01 Hz value and the log (tau / s) value when the material enters anaerobic corrosion from aerobic corrosion are taken as critical points, whether the material is in an aerobic corrosion state, a low-oxygen corrosion state or an anaerobic corrosion state is judged according to the measured Z0.01 Hz value and log (tau / s) value, and the coverage degree of corrosion products on the surface of the material and whether oxygen leakage occurs in a treatment environment are also judged. The method is suitable for rapidly evaluating the material corrosion rate and influence factors in the high-level radioactive waste geological disposal environment, and has the characteristics of simplicity, high operability, high accuracy and good long-term stability.

Description

Technical Field

[0001] The present invention relates to the field of monitoring and characterization of metal corrosion behavior, in particular to a rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste. Background Art

[0002] High-level radioactive waste (HLW) mainly refers to high-level radioactive liquid waste and its solidified body generated from the reprocessing of spent fuel. HLW is a special kind of waste that poses a potentially huge threat to the environment. The radionuclides contained in HLW are characterized by strong radioactivity, high toxicity, long half-life and heat generation. Once they enter the human living environment, they are extremely harmful and difficult to eliminate. Therefore, the safe disposal of HLW has become a major issue affecting the sustainable development of nuclear energy, environmental protection and the well-being of future generations, and is also a major problem in science, technology and engineering.

[0003] Currently, the internationally recognized method for the safe disposal of HLW is deep geological disposal, that is, burying HLW in a stable geological body about 400-1000 m deep from the ground surface to effectively isolate it from the biosphere. The disposal container is generally made of metal materials, and its main safety function is to contain HLW, prevent groundwater from infiltrating, and the containment time is not less than 1000 years. Therefore, it is very necessary to study the corrosion evolution behavior of the disposal container material in the geological disposal repository environment.

[0004] Since it is inevitable that a certain amount of oxygen will remain in the disposal repository for a considerable period of time after its closure during the disposal process, the consumption and evolution characteristics of dissolved oxygen will be directly related to the corrosion rate characteristics of the disposal container material; in addition, when oxygen leakage occurs in the disposal repository, it will also significantly affect the corrosion of the disposal container material and accelerate its containment failure. In order to better study the corrosion evolution behavior and its evolution characteristics of the disposal container material in the high-level radioactive waste geological disposal repository, and identify the accident of oxygen leakage in the disposal repository, it is very necessary to develop and design a rapid evaluation method for the corrosion rate and influencing factors of materials in the high-level radioactive waste geological disposal environment. Summary of the Invention

[0005] Aiming at the engineering requirements of the geological disposal of high-level radioactive waste, the purpose of the present invention is to provide a rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste. The principle of this evaluation method is clear, the steps are simple, the parameters are easy to obtain, and this evaluation method has high accuracy, strong operability and good long-term stability, and is suitable for the rapid evaluation of the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste.

[0006] A rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste. Two indicators are obtained through electrochemical impedance spectroscopy (EIS) measurement and relaxation time distribution (DRT) analysis of EIS data: one is the impedance modulus value corresponding to 0.01 Hz, i.e., |Z| 0.01Hz value; the other is the time constant corresponding to the dissolved oxygen reduction reaction, i.e., log(τ / s) value;

[0007] The materials in the geological disposal environment of high-level radioactive waste are used to simulate the materials of geological disposal containers for high-level radioactive waste, including low-carbon steel, copper, cast iron, nickel-based alloys, and titanium alloys;

[0008] The geological disposal environment of high-level radioactive waste includes the groundwater environment of the surrounding rock strata of the disposal repository and the backfill material environment around the disposal container, including the environment containing bentonite with different water contents;

[0009] The corrosion system is used to simulate the closed environment characteristics of the geological disposal repository of high-level radioactive waste. According to the environment where the disposal repository is located and the characteristics of the groundwater in the surrounding rock strata, the environmental parameters of the closed system are different, such as SO4 2- concentration, Cl - concentration, HCO3 - / CO3 2- concentration, pH value, pressure, and water content of the backfill material;

[0010] For the electrochemical impedance spectroscopy measurement, first, the candidate material is processed and prepared into a working electrode for corrosion electrochemistry testing, and then the EIS data of the working electrode is collected using a traditional three-electrode system or a two-electrode system, and the lower limit of the collection frequency is not less than 0.01 Hz;

[0011] The |Z| 0.01Hz value is obtained by reading the impedance modulus value corresponding to 0.01 Hz in the impedance modulus value diagram of the electrochemical impedance spectroscopy, and is used to reflect the ease of electrochemical polarization of the candidate material in the geological disposal environment of high-level radioactive waste;

[0012] The log(τ / s) value is obtained by performing DRT analysis on the measured electrochemical impedance spectroscopy, and is used to reflect the ease of the dissolved oxygen reduction reaction in the corrosion system, which is related to the content of dissolved oxygen.

[0013] This method is based on electrochemical impedance spectroscopy measurement and relaxation time distribution analysis to obtain two indicators, namely: the impedance modulus value |Z| 0.01Hz value corresponding to 0.01 Hz and the time constant log(τ / s) value corresponding to the dissolved oxygen reduction reaction; taking the |Z| 0.01Hz value and log(τ / s) value when the material changes from aerobic corrosion to anaerobic corrosion as the critical points, with the log(τ / s) value evolving as the X-axis and the |Z| 0.01HzThe value evolves along the Y-axis to construct log(τ / s)-|Z| 0.01Hz plane coordinate system.

[0014] When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the third quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is sufficient, the candidate material is in the aerobic corrosion stage, and the coverage of the corrosion products on the surface of the candidate material is low. At this time, the corrosion rate of low-carbon steel > 24.5 μm / y.

[0015] When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the fourth quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is sufficient, the candidate material is in the aerobic corrosion stage, but there is a large coverage of corrosion products on the surface of the candidate material, that is, the coverage of the corrosion products is high.

[0016] When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the second quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is low, the candidate material is in the low-oxygen corrosion stage, and at this time, the corrosion rate of low-carbon steel < 24.5 μm / y.

[0017] When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the first quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen in the corresponding corrosion system has been consumed, and the candidate material has entered the anaerobic corrosion stage.

[0018] When the measured |Z| 0.01Hz value and the log(τ / s) value show a tendency to move from the third or fourth quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system to the first or second quadrant, which represents that the oxygen in the corrosion system is gradually consumed by the corrosion reaction, and the oxygen content in the corrosion system is gradually decreasing.

[0019] When the measured |Z| 0.01Hz value and the log(τ / s) value show a tendency to move from the first or second quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system to the third or fourth quadrant, which represents that the corrosion system leaks and external oxygen enters the corrosion system.

[0020] The present invention utilizes the technical advantages of DRT analysis, which can identify the time constants contained in the EIS spectrum and can be associated with the electrochemical reactions involved in the corrosion process. By DRT analysis, the time constant corresponding to the reduction of dissolved oxygen is identified. At the same time, since the time constant log(τ / s) corresponding to the reduction of dissolved oxygen is closely related to the concentration of oxygen, the evolution of the dissolved oxygen concentration in the corrosion system and the accident of oxygen leakage in the corrosion system can be further judged through the evolution of the log(τ / s) value.

[0021] Although both the increase in the coverage of the corrosion product on the surface of the candidate material for the disposal container and the decrease in the oxidizing property of the corrosion system can show a rapid increase in the time constant, the change in the polarization resistance caused by the accumulation of the corrosion product is not significant, while the gradual decrease in the oxygen partial pressure can cause an increase in the order of magnitude of the polarization resistance. The increase in the time constant and the increase in the polarization resistance both mean a decrease in the corrosion rate of the candidate material for the disposal container in the corrosion system. Therefore, through a single EIS measurement, two parameters closely related to the corrosion rate of the candidate material for the disposal container in the corrosion system can be obtained simultaneously, namely: the value of |Z| 0.01Hz and the value of log(τ / s).

[0022] According to the quadrant position of the measured values of |Z| 0.01Hz and log(τ / s) in the log(τ / s)-|Z| 0.01Hz coordinate system during the corrosion process of materials in the geological disposal environment of high-level radioactive waste, the evolution of the corrosion rate of materials in the geological disposal environment of high-level radioactive waste and the impact of oxygen leakage in the disposal repository can be rapidly evaluated, featuring simple method, easy-to-obtain parameters, strong operability, high accuracy, good long-term stability and real-time evaluation.

[0023] The advantages and beneficial effects of the present invention are as follows:

[0024] The EIS measurement based on the three-electrode system and the two-electrode system adopted by the present invention is a commonly used method in the field of corrosion electrochemistry, and the DRT analysis method of EIS data is simple and has high accuracy, accurately identifying the evolution of the time constant log(τ / s) corresponding to the reduction process of dissolved oxygen during the aerobic / anaerobic corrosion process. Therefore, only two parameters, namely the value of |Z| 0.01Hz and the value of log(τ / s), are required to accurately evaluate the evolution of the corrosion rate of materials in the geological disposal environment of high-level radioactive waste and the influence of factors such as oxygen leakage in the disposal repository, effectively avoiding the disadvantages of low accuracy and complexity of traditional identification methods.

[0025] The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste provided by the present invention has simple steps, clear principles, high identification accuracy, and is simple in method, easy to obtain parameters, and strong in operability. It is applicable to the rapid evaluation and identification of the evolution of the corrosion rate of materials in the geological disposal environment of high-level radioactive waste and the accident of oxygen leakage in the disposal repository. Description of the Drawings

[0026] Figure 1 Evolution results of two parameters, namely the |Z| value and the log(τ / s) value, with corrosion time during the corrosion process of Q345R low-carbon steel in the groundwater environment of the open Beishan repository with an initial oxygen concentration of 8 ppm 0.01Hz Value and log(τ / s) value two parameters with the evolution results of the corrosion time diagram;

[0027] Figure 2 Evolution results of two parameters, namely the |Z| value and the log(τ / s) value, with corrosion time during the corrosion process of Q345R low-carbon steel in the groundwater environment of the closed Beishan repository with an initial oxygen concentration of 8 ppm 0.01Hz Value and log(τ / s) value two parameters with the evolution results of the corrosion time diagram;

[0028] Figure 3 For the groundwater environment of the closed Beishan repository with an initial oxygen concentration of 10 -4 ppb, evolution results of two parameters, namely the |Z| value and the log(τ / s) value, with corrosion time during the corrosion process of Q345R low-carbon steel 0.01Hz Value and log(τ / s) value two parameters with the evolution results of the corrosion time diagram;

[0029] Figure 4 For the groundwater environment of the open Beishan repository with an initial oxygen concentration of 10 -4 ppb, evolution results of two parameters, namely the |Z| value and the log(τ / s) value, with corrosion time after removing the glove box after the Q345R low-carbon steel has been corroded for a period of time 0.01Hz Value and log(τ / s) value two parameters with the evolution results of the corrosion time diagram.

[0030] Next, the present invention will be further elaborated in detail through examples. Specific embodiments

[0031] To facilitate the understanding of the present invention, the present invention will be described more comprehensively with reference to the relevant drawings. Typical embodiments of the present invention are given in the drawings. However, the present invention is applicable to many different scenarios and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosed content of the present invention more thorough and comprehensive.

[0032] It should be noted that all the technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0033] Example 1

[0034] In this example, the corrosion simulation solution uses the BS-01 groundwater of the Beishan repository. After boiling and cooling at room temperature and normal pressure, it is reserved for use. At this time, the oxygen content in the water is about 8 ppm.

[0035] Two electrodes made of Q345R low-carbon steel were exposed to 400 mL of this groundwater, and were left open to the atmosphere at room temperature and atmospheric pressure. At this time, the dissolved oxygen content in the corrosion solution could always be regarded as approximately 8 ppm.

[0036] During the corrosion process, EIS spectra were measured for the two electrodes made of Q345R low-carbon steel, and the EIS spectra were analyzed using DRT to obtain the log(τ / s) values, and the |Z| 0.01Hz values and the evolution curves of the log(τ / s) values with corrosion time were recorded.

[0037] It is shown by Figure 1 that during the corrosion process, the |Z| 0.01Hz values fluctuated little and were considered to change little. However, as the corrosion products gradually accumulated on the surface of the Q345R low-carbon steel electrode, the log(τ / s) values showed an increasing trend. At this time, the corrosion rate of the low-carbon steel > 24.5 μm / y, and the measured |Z| 0.01Hz values and the log(τ / s) values were located in the third quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system, corresponding to the sufficient dissolved oxygen content in the corrosion system at this time, the candidate material being in the aerobic corrosion stage, and the coverage of the corrosion products on the surface of the candidate material being relatively low.

[0038] It can be seen that the results of this example show that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste of the present invention is applicable to the rapid evaluation of the corrosion rate of materials in the geological disposal environment of high-level radioactive waste.

[0039] Example 2

[0040] In this example, the corrosion simulation solution was the BS-01 groundwater of the Beishan disposal repository. After being boiled and cooled at room temperature and atmospheric pressure, it was reserved for use. At this time, the oxygen content in the water was approximately 8 ppm.

[0041] The corrosion system was prepared in the atmospheric environment. Two electrodes made of Q345R low-carbon steel were exposed to 400 mL of this groundwater, and then the corrosion system was sealed under room temperature and atmospheric pressure conditions to isolate it from the surrounding air environment. At this time, the initial oxygen content in the corrosion solution was approximately 8 ppm.

[0042] During the corrosion process, EIS spectra were measured for the two electrodes made of Q345R low-carbon steel, and the EIS spectra were analyzed using DRT to obtain the log(τ / s) values, and the |Z| 0.01Hz values and the evolution curves of the log(τ / s) values with corrosion time were recorded.

[0043] It is shown by Figure 2 that at the initial stage of corrosion, the dissolved oxygen content in the corrosion system was relatively large, and the measured |Z| 0.01HzThe values of and log(τ / s) are located in the third quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system. At this time, the corrosion rate of low-carbon steel > 24.5 μm / y. However, as the corrosion time prolongs, the rapid consumption of dissolved oxygen causes the measured |Z| 0.01Hz values and log(τ / s) values to quickly move to the second quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system. After that, as the corrosion continues, the |Z| 0.01Hz values fluctuate less and are considered to change little. However, as the corrosion products gradually accumulate on the surface of the Q345R low-carbon steel electrode, the log(τ / s) values show an increasing trend. At this time, the corrosion rate of low-carbon steel < 24.5 μm / y, and the measured |Z| 0.01Hz values and log(τ / s) values show a gradual trend of moving towards the first quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system, corresponding to the gradual consumption of dissolved oxygen and further decrease in content in the corrosion system at this time, and the candidate material gradually changes from the low-oxygen corrosion stage to the anaerobic corrosion stage.

[0044] It can be seen that the results of this embodiment show that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste of the present invention is applicable to the rapid evaluation of the corrosion rate of materials in the geological disposal environment of high-level radioactive waste.

[0045] Example 3

[0046] In this embodiment, the corrosion simulation solution uses the BS-01 groundwater of Beishan disposal repository. After boiling and cooling at room temperature and normal pressure, it is reserved for use. At this time, the oxygen content in the water is about 8 ppm.

[0047] The corrosion system is prepared in a low-oxygen glove box (the gas-phase oxygen content is less than 0.1 ppm). The two electrodes made of the corrosion simulation liquid and Q345R low-carbon steel are placed in the glove box. Then the corrosion system is prepared and sealed. At this time, the initial dissolved oxygen content in the corrosion solution is about 10 -4 ppb.

[0048] During the corrosion process, EIS spectra are measured for the two electrodes made of Q345R low-carbon steel, and the EIS spectra are analyzed by DRT to obtain the log(τ / s) values, and the evolution curves of the |Z| 0.01Hz values and log(τ / s) values with the corrosion time are recorded.

[0049] As shown by Figure 3 at the initial stage of corrosion, the measured |Z| 0.01Hz values and log(τ / s) values are located in the log(τ / s)-|Z| 0.01HzIn the second quadrant of the coordinate system, but as the corrosion time prolongs and the corrosion products on the surface of the Q345R low-carbon steel electrode gradually accumulate, |Z| 0.01Hz value and log(τ / s) value show a tendency to move towards the first quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system. This corresponds to the gradual consumption of dissolved oxygen in the corrosion system at this time, with a further decrease in content. The candidate material gradually transforms from the low-oxygen corrosion stage to the anaerobic corrosion stage.

[0050] It can be seen that the results of this embodiment show that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste of the present invention is applicable to the rapid evaluation of the transformation from aerobic corrosion / anaerobic corrosion of materials in the geological disposal environment of high-level radioactive waste.

[0051] Example 4

[0052] In this embodiment, the corrosion simulation solution uses the BS-01 groundwater of Beishan disposal repository. After boiling and cooling at room temperature and normal pressure, it is reserved for use. At this time, the oxygen content in the water is about 8 ppm.

[0053] The corrosion system is prepared in a low-oxygen glove box (the gas-phase oxygen content is less than 0.1 ppm). The corrosion simulation solution and the two electrodes made of Q345R low-carbon steel are placed in the glove box. Then, the corrosion system is prepared. The two electrodes made of Q345R low-carbon steel are exposed to 400 mL of this groundwater, and it is left open to the atmospheric environment in the glove box. At this time, the dissolved oxygen content in the corrosion solution can always be regarded as about 10 -4 ppb. After corroding for a period of time, the open corrosion system is removed from the glove box and the corrosion system is left open to the indoor atmospheric environment.

[0054] During the corrosion process, EIS spectra are measured for the two electrodes made of Q345R low-carbon steel, and the EIS spectra are analyzed by DRT to obtain the log(τ / s) value, and the evolution curves of the |Z| 0.01Hz value and the log(τ / s) value with the corrosion time are recorded.

[0055] As shown by Figure 4 , when the corrosion system is in the glove box and remains open, at the initial stage of corrosion, the measured |Z| 0.01Hz value and log(τ / s) value are located in the second quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system. However, as the corrosion time prolongs and the corrosion products on the surface of the Q345R low-carbon steel electrode gradually accumulate, the measured |Z| 0.01Hz value and log(τ / s) value gradually increase and show a tendency to stabilize. The candidate material Q345R low-carbon steel is in the low-oxygen corrosion stage; but when the corrosion system is removed from the glove box and left open to the indoor atmospheric environment, the measured |Z|0.01Hz The values of [value] and log(τ / s) rapidly move towards the third quadrant of the log(τ / s)-|Z| 0.01Hz coordinate system. After that, as the corrosion products on the surface of the Q345R low-carbon steel electrode gradually accumulate, the value of log(τ / s) shows an increasing trend, corresponding to the sufficient dissolved oxygen content in the corrosion system at this time, and the candidate material is in the stage of aerobic corrosion.

[0056] It can be seen that the results of this embodiment show that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste of the present invention is applicable to the rapid evaluation of oxygen leakage accidents occurring in the geological disposal environment of high-level radioactive waste.

[0057] The results of the embodiment show that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste provided by the present invention is applicable to the rapid evaluation and identification of the evolution of the corrosion rate of materials and the occurrence of oxygen leakage accidents in the geological disposal repository of high-level radioactive waste. It can be seen that the rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste of the present invention has the characteristics of simple steps, clear principle, high identification accuracy, simple method, easy-to-obtain parameters, and strong operability.

[0058] The above-described embodiments merely represent one implementation manner of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements are made. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the appended claims.

Claims

1. A rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste, characterized in that Two indicators are obtained through electrochemical impedance spectroscopy (EIS) measurement and relaxation time distribution (DRT) analysis of EIS data: one is the impedance modulus value corresponding to 0.01 Hz, i.e., |Z| 0.01Hz value; the other is the time constant corresponding to the dissolved oxygen reduction reaction, i.e., log(τ / s) value; The materials in the geological disposal environment of high-level radioactive waste are used to simulate the materials of the geological disposal container for high-level radioactive waste, including low-carbon steel, copper, cast iron, nickel-based alloy, and titanium alloy; The geological disposal environment of high-level radioactive waste includes the groundwater environment of the surrounding rock strata of the repository and the backfill material environment around the disposal container, including the environment containing bentonite with different water contents; The corrosion system is used to simulate the characteristics of the closed environment of a geological repository for high-level radioactive waste. According to the environment where the repository is located and the characteristics of the groundwater in the surrounding rock strata, the environmental parameters of the closed system are different, including SO4 2- concentration, Cl - concentration, HCO3 - / CO3 2- concentration, pH value, pressure, and water content of the backfill material; For the measurement of electrochemical impedance spectroscopy, first, the candidate materials are processed into working electrodes for corrosion electrochemistry tests, and then the EIS data of the working electrodes are collected by using a traditional three-electrode system or two-electrode system, and the lower limit of the collection frequency is not less than 0.01 Hz; The described |Z| 0.01Hz value, obtained by reading the impedance modulus value corresponding to 0.01 Hz in the impedance modulus value diagram of the electrochemical impedance spectrum, is used to reflect the ease of electrochemical polarization of the candidate material in the geological disposal environment of high-level radioactive waste; The log(τ / s) value is obtained by performing DRT analysis on the measured electrochemical impedance spectroscopy, which is used to reflect the difficulty of the reduction reaction of dissolved oxygen in the corrosion system and is related to the content of dissolved oxygen.

2. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 1, characterized in that This method obtains two indicators based on electrochemical impedance spectroscopy measurement and relaxation time distribution analysis, namely: the impedance modulus value |Z| corresponding to 0.01 Hz 0.01Hz value and the time constant log(τ / s) value corresponding to the dissolved oxygen reduction reaction; with the |Z| 0.01Hz value and the log(τ / s) value when the material changes from aerobic corrosion to anaerobic corrosion as the critical points, with the evolution of the log(τ / s) value as the X-axis and the |Z| 0.01Hz value evolution as the Y-axis, a log(τ / s)-|Z| 0.01Hz plane coordinate system is constructed.

3. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the third quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is sufficient, the candidate material is in the stage of aerobic corrosion, and the coverage of the corrosion product on the surface of the candidate material is low. At this time, the corrosion rate of low-carbon steel > 24.5 μm / y.

4. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that, When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the fourth quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is sufficient, the candidate material is in the stage of aerobic corrosion, but there is already a large coverage of corrosion products on the surface of the candidate material, that is, the coverage of corrosion products is high.

5. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that, When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the second quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the dissolved oxygen content in the corresponding corrosion system is low, and the candidate material is in the low-oxygen corrosion stage. At this time, the corrosion rate of low-carbon steel is <24.5 μm / y.

6. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that When the measured |Z| 0.01Hz value and the log(τ / s) value are located in the first quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system, it indicates that the dissolved oxygen in the corresponding corrosion system has been consumed, and the candidate material has entered the anaerobic corrosion stage.

7. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that, When the measured |Z| 0.01Hz value and the log(τ / s) value show a trend of moving from the third or fourth quadrant to the first or second quadrant in the log(τ / s)-|Z| 0.01Hz plane coordinate system, it represents that the oxygen in the corrosion system is gradually consumed by the corrosion reaction, and the oxygen content in the corrosion system gradually decreases.

8. The rapid evaluation method for the corrosion rate and influencing factors of materials in the geological disposal environment of high-level radioactive waste according to claim 2, characterized in that When the measured |Z| 0.01Hz value and the log(τ / s) value show a tendency to move from the first or second quadrant of the log(τ / s)-|Z| 0.01Hz plane coordinate system to the third or fourth quadrant, it represents that there is a leakage in the corrosion system and external oxygen enters the corrosion system.

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