A method and system for testing the corrosion resistance of hot-dip galvanized workpieces

Abstract

This application relates to the field of metal corrosion resistance testing technology, specifically to a method and system for testing the corrosion resistance of hot-dip galvanized workpieces. The method includes: acquiring current data at different potential points during corrosion resistance testing of multiple groups of hot-dip galvanized workpieces; obtaining a first fluctuation index of the current data for each test group based on the stability and degree of current change within each interval; obtaining a second fluctuation index of the current data for each test group based on the similarity between the corresponding polarization curves of different test groups; constructing the reliability of the current data for different test groups, thereby obtaining contribution weights; calculating the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece based on the contribution weights; and evaluating the comprehensive corrosion resistance of batches of hot-dip galvanized workpieces. This application can improve the accuracy of hot-dip galvanized corrosion resistance testing.

Description

Technical Field

[0001] This application relates to the field of metal corrosion resistance testing technology, specifically to a method and system for testing the corrosion resistance of hot-dip galvanized workpieces. Background Technology

[0002] Existing methods for testing corrosion resistance include neutral salt spray testing and electrochemical testing. Among them, electrochemical testing is a rapid, sensitive, and real-time monitoring method that can detect the corrosion resistance of the object being tested within tens of minutes.

[0003] Electrochemical testing methods (such as the Tafel polarization curve test) construct a three-electrode system based on the hot-dip galvanized workpiece under test in an electrolyte environment to detect the current response signal generated by the working electrode, obtain potential-current relationship data, and plot a polarization curve. This allows for the calculation of data reflecting the corrosion rate of the workpiece, such as corrosion potential and corrosion current density, to measure its corrosion resistance. However, in actual testing, unstable environmental factors and the hot-dip galvanizing state of the workpiece surface can cause fluctuations in the acquired current response signal data, leading to differences in the polarization curve and affecting the accuracy of data calculations such as corrosion potential. This makes it difficult to accurately assess the corrosion resistance of hot-dip galvanized workpieces. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this application is to provide a method and system for testing the corrosion resistance of hot-dip galvanized workpieces. The specific technical solution adopted is as follows: This application provides a method for testing the corrosion resistance of hot-dip galvanized workpieces, including the following steps: Current data at different potential points were obtained during the corrosion resistance test of multiple sets of hot-dip galvanized workpieces. The characteristics of current change at different potential points are analyzed to divide the current data of each test group into intervals. The first fluctuation index of the current data of each test group is obtained by using the current stability and the degree of current change in each interval. The polarization curves corresponding to each test group are obtained by fitting the current data at different potential points of each test group. Based on the similarity between the polarization curves corresponding to different test groups, the second fluctuation index of the current data of each test group is obtained. The reliability of the current data of different test groups is constructed based on the first and second fluctuation indices of the current data of each test group, and then the contribution weight is obtained. Based on the contribution weight, the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece are calculated, and the corrosion resistance performance of the hot-dip galvanized workpiece is detected.

[0005] Preferably, the current data for the nth test group The difference sequence is obtained, and the mutation point threshold of the difference sequence is extracted. The potential points corresponding to the data in the difference sequence that exceed the mutation point threshold are used as segmentation point pairs. Divide the data into segments to obtain the intervals.

[0006] Preferably, before obtaining the first volatility index, for the first... The first test group Calculate the interval. The first parameter of each interval : In the formula, It is an exponential function. For the first The average sequence length of each interval and its neighboring intervals For the first The sequence length of the nth interval, where the nth interval is the sequence length of the nth interval. Taking the interval as the center, take the left and right sides of it. Each interval is used as its neighborhood interval.

[0007] Preferably, before obtaining the first volatility index, for the first... The first test group Calculate the interval. The second parameter of each interval : ,in To find the maximum value of the function, For the first The rate of change of current in each interval For the first The average rate of change of current in each interval and its neighboring intervals Indicates the first The maximum rate of change of current in each interval and its neighboring intervals. To avoid extremely small positive numbers with a denominator of zero.

[0008] Preferably, the first fluctuation index of the current data for each test group is obtained as follows: In the formula, Let K be the first fluctuation index of the nth set of current data, and K be the number of intervals. The first The first and second parameters of each interval are given, where if K is less than a preset value, the first fluctuation index is zero.

[0009] Preferably, the process for obtaining the second fluctuation index of the current data for each test group is as follows: ,in, This is the first fluctuation index of the nth set of current data. It is an exponential function. Let N be the cosine similarity, and N be the number of test groups. These are the logarithmic sequences of current densities in the polarization curves corresponding to the nth and mth test groups, respectively.

[0010] Preferably, the reliability of the data from the different test groups is obtained specifically as follows: In the formula, To determine the reliability of the nth set of current data, These are the first and second fluctuation indices of the current data in the nth group, respectively, where N is the number of test groups. To avoid extremely small positive numbers with a denominator of zero.

[0011] Preferably, the contribution weight is obtained as follows: In the formula, The contribution weight for the nth group of current data.

[0012] Preferably, the process for obtaining the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece is as follows: The corrosion potential and corrosion current density of the hot-dip galvanized workpieces in each test group were calculated using the Tafel extrapolation method. The overall corrosion potential of the hot-dip galvanized workpiece was then determined. Comprehensive corrosion current density They are respectively: Among them, the first The corrosion potential and corrosion current density of the polarized fine wires corresponding to the group test were obtained using the Tafel extrapolation method. .

[0013] This application also provides a corrosion resistance testing system for hot-dip galvanized workpieces, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any of the above-described corrosion resistance testing methods for hot-dip galvanized workpieces.

[0014] As can be seen from the above, the corrosion resistance testing method and system for hot-dip galvanized workpieces provided in this application have at least the following beneficial effects: To address the issue that the electrochemical current response data is subject to localized abnormal fluctuations due to the coating process on the hot-dip galvanized workpiece surface and interference from factors in the testing environment, which can lead to errors in subsequent calculations of corrosion potential and corrosion current density parameters based on polarization curves and hinder accurate assessment of the workpiece's corrosion resistance, this application employs the same testing conditions to conduct electrochemical corrosion resistance tests on multiple groups of hot-dip galvanized workpieces. A first fluctuation index is constructed by statistically analyzing the abnormal fluctuation characteristics of the current response signal data in a single test group to reflect the stability of individual data. Then, a second fluctuation index is constructed by analyzing the sample consistency characteristics of the polarization curves in multiple test groups to reflect the consistency of corrosion kinetics among different groups of data. The reliability of different samples is represented by the first and second fluctuation indices, and differentiated weights are assigned to different samples to weight the Tafel parameters (corrosion potential, corrosion current density, etc.), thereby improving the accuracy and stability of the corrosion resistance test for hot-dip galvanized workpieces. Attached Figure Description

[0015] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 A flowchart illustrating the steps of a method for testing the corrosion resistance of hot-dip galvanized workpieces provided in this application. Detailed Implementation

[0017] To further illustrate the technical means and effects adopted by this application to achieve the intended purpose of the invention, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a method and system for testing the corrosion resistance of hot-dip galvanized workpieces proposed in this application. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0018] Unless otherwise specified and limited, terms such as “comprising,” “including,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the article or device that includes said element. Furthermore, the term “and / or” as used herein includes any and all combinations of one or more of the associated listed items. All technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0019] The following description, in conjunction with the accompanying drawings, details the specific scheme of the method and system for testing the corrosion resistance of hot-dip galvanized workpieces provided in this application.

[0020] Please see Figure 1 The document illustrates a flowchart of a method for testing the corrosion resistance of hot-dip galvanized workpieces according to an embodiment of this application, including the following steps: Step 1: Obtain current data at different potential points during the corrosion resistance test of multiple sets of hot-dip galvanized workpieces.

[0021] Select The corrosion resistance of each hot-dip galvanized workpiece was tested. The size can be set by the implementer according to the testing needs. This embodiment does not impose special restrictions. However, to prevent the test results from being affected by excessively small sample sizes, the following measures are taken: The value is greater than 10 in this embodiment. Take 20.

[0022] Furthermore, the selected hot-dip galvanized workpieces undergo pretreatment, including cutting, grinding, and cleaning, to ensure the surface of the test sample is clean. The pretreated hot-dip galvanized workpieces are then insulated and encapsulated, with each workpiece exposing an area of ​​equal size as a working electrode. The size of the exposed area can be set by the implementer according to the testing requirements and is not subject to special restrictions; in this embodiment, the exposed area is 1 cm². 2 .

[0023] A three-electrode system was constructed by mounting the working electrode (the hot-dip galvanized workpiece sample under test), a reference electrode, and a counter electrode together in an electrochemical corrosion test cell. A platinum sheet was used as the reference electrode, and a saturated calomel electrode was used as the counter electrode. An electrolyte, such as a 3.5% NaCl (sodium chloride) solution, was added to the test cell to simulate the corrosive environment. The test temperature was 25°C. A potential scan was applied to the working electrode using an electrochemical workstation at a scan rate of 0.1 mV / s to begin the electrochemical corrosion resistance test.

[0024] The current response signal data of the working electrode was acquired using an electrochemical workstation at a sampling frequency of 100 Hz. Each test group used the same starting potential, ending potential, and potential scan rate to ensure that the acquired potential-current data sequence lengths were completely consistent and that the potential points corresponded one-to-one.

[0025] Electrochemical corrosion resistance testing methods based on the Tafel polarization curve method can characterize the corrosion rate of the tested object by constructing a polarization curve from the current response data of the working electrode. However, in actual testing, the data obtained is easily affected by various factors, leading to abnormal changes and local fluctuations in the polarization curve. This, in turn, affects the accuracy of calculating parameters such as corrosion potential and corrosion current density, making it difficult to accurately assess the corrosion resistance of hot-dip galvanized workpieces. For example, the surface of hot-dip galvanized workpieces may have a passivation layer or a locally uneven coating structure, causing the working electrode to deviate from the normal corrosion kinetic model during corrosion testing. In addition, electromagnetic interference in the testing equipment can also cause a certain degree of random disturbance in the current response signal, superimposed with instantaneous anomalies, resulting in local abnormal fluctuations in the polarization curve.

[0026] To address the aforementioned issues, this invention employs identical testing conditions to conduct electrochemical corrosion resistance tests on multiple groups of hot-dip galvanized workpieces. A first fluctuation index is constructed by statistically analyzing the abnormal fluctuation characteristics of the current response signal data in a single test group, reflecting the stability of individual data points. Then, a second fluctuation index is constructed by analyzing the sample consistency characteristics of the polarization curves in multiple test groups, characterizing the corrosion kinetic consistency between different groups of data. Based on the first and second fluctuation indices, the reliability of different samples is represented. Differential weights are assigned to different samples to weight the Tafel parameters (corrosion potential, corrosion current density, etc.), thereby improving the accuracy and stability of the corrosion resistance test for hot-dip galvanized workpieces. The specific steps for obtaining the first and second fluctuation indices are as follows.

[0027] Step 2: Analyze the current change characteristics at different potential points to divide the current data of each test group into intervals. Utilize the current stability and degree of change within each interval to obtain the first fluctuation index of the current data of each test group.

[0028] Specifically, in the acquired current response signal data, the first... Group test number The current data corresponding to each potential point is represented as follows: ,in This represents the total number of potentials.

[0029] The current response signal data is a potential-current data sequence (reflecting the process of current changing with potential), which represents the magnitude of the current responded by the working electrode when different potentials are applied to it. In electrochemical corrosion resistance testing, when a potential is applied to the working electrode, the metal on the electrode surface undergoes a redox reaction, and the magnitude of the response current directly reflects the change in the electrochemical reaction rate of the metal on the electrode surface.

[0030] Ideally, the coating on the working electrode surface is uniform, and the electrochemical reaction rate on the surface exhibits a smooth and continuous trend with changes in potential; that is, the current maintains a stable gradient within a local range as the potential increases or decreases. However, in actual testing, issues with the coating process on the workpiece surface can lead to uneven coating thickness, micropores, and other structural defects that affect the uniformity of the coating reaction. External factors (such as electromagnetic interference from the workstation) can also cause local abrupt disturbances in the current response sequence, disrupting its continuity and stability. Consequently, the fitted Tafel polarization curve deviates from the theoretical trend in local areas, resulting in deviations in the corrosion parameters obtained from subsequent analysis of the Tafel curve.

[0031] Based on the above analysis, a first fluctuation index is constructed by analyzing the fluctuation characteristics of the current response data in a single set of tests, which is used to reflect the stability of the changes in the current response data during the test.

[0032] Specifically, firstly, regarding the current data of the nth test group... ,calculate The difference sequence is obtained by first-order forward difference of the current amplitude at each potential. The first-order forward difference value represents the rate of change of the current amplitude. When a sudden change in current amplitude occurs at a certain potential, the first-order forward difference value is relatively large. Then, the threshold for abrupt changes in the difference sequence is constructed using the three-standard-deviation rule. Potential points corresponding to first-order forward difference values ​​exceeding the threshold range are used as segmentation points. Perform segmentation processing to obtain There are several intervals, where K is the number of intervals. The three-standard-deviation rule is a current technique, and the specific process will not be elaborated here.

[0033] Understandably, a larger first-order forward difference value indicates a greater change in current amplitude, suggesting a greater difference in current amplitude between the two potentials and a higher likelihood of abrupt changes in current amplitude. Because the rate of chemical reaction in the metal varies with the changing potential during electrochemical testing, the overall current response data will not change smoothly and stably. As the reaction progresses, dramatic reactions may occur within a certain potential range, resulting in different magnitudes of the response current in different potential ranges. Abrupt changes in current amplitude may correspond to uneven coating on the workpiece surface, interference from external disturbances, or entry into a potential range where the workpiece surface coating is particularly sensitive.

[0034] Each segmented interval can be viewed as an interval where the current response data exhibits a stable trend. Specifically, if... If the trend of the current response data is very stable throughout the entire test process, and there are no sudden changes in local current data caused by external disturbances, then no further statistical analysis will be performed, and the first fluctuation index is 0.

[0035] So for the first... The first test group For each interval, calculate the sequence length of that interval. and rate of change of current , This represents the average of the absolute values ​​of the current amplitude differences between adjacent potential points within the k-th interval. The calculation of the rate of change is a prior art technique and will not be elaborated upon in this embodiment. Further, taking the k-th interval as an example... Taking the interval as the center, take the left and right sides of it. Each interval is used as a neighborhood interval. The size can be set by the implementer according to the implementation scenario, without special restrictions. In this embodiment... The value of is 2. When the k-th interval is located at either the beginning or end, and the number of intervals to its left or right is less than H, all existing single-sided or double-sided intervals are taken as neighboring intervals for calculation. Further, the k-th interval is calculated... The first parameter of each interval ,in It is an exponential function. For the first The average sequence length of each interval and its neighboring intervals.

[0036] It is understandable that the sequence length of an interval represents the potential range of a stable change in the response current. As the electrochemical reaction proceeds, the reaction rate varies within a local potential range, causing abrupt changes in the response current within a local area. However, this change is not caused by external disturbances but by a stable electrochemical reaction process. Therefore, compared to abnormal fluctuations in current amplitude caused by instantaneous external disturbances, abrupt changes in current amplitude due to electrochemical reaction changes are more stable, and their interval length is longer. By statistically analyzing the... The ratio of the sequence length of an interval to the mean interval length within its local range can reflect the degree of anomaly of that interval. much smaller When, it means the first The first interval may be caused by a sudden change in current amplitude due to external disturbances. Since the sequence length of this interval is relatively short, then the second... The larger the first parameter of each interval, the higher the degree of anomaly; conversely, the smaller the first parameter, the higher the degree of anomaly. Greater than Or when the two are close, it indicates the first Each range represents a sudden change in current amplitude due to the electrochemical reaction; the smaller the first parameter, the lower the degree of anomaly.

[0037] Furthermore, calculate the first... The second parameter of each interval ,in To find the maximum value of the function, For the first The average rate of change of current in each interval and its neighboring intervals Indicates the first The maximum rate of change of current in each interval and its neighborhood interval is used to normalize the molecule. To avoid extremely small positive numbers with a denominator of zero, this embodiment uses a value of 0.001.

[0038] Understandably, the rate of change of current represents the average fluctuation of current within a certain range. A larger value indicates a more drastic change in current, while a smaller value indicates a more stable change. Therefore, by calculating... It can reflect the first The larger the difference between the current fluctuation within a given interval and the average current fluctuation within its neighboring interval, the more drastic the current fluctuation within that interval is, and the more likely that the interval is to be affected by external disturbances that cause abnormal jumps in current amplitude. In this case, the second parameter will be larger. Conversely, the smaller the value, or even less than 0, the smaller the value, indicating that the corresponding current within that interval maintains a stable gradient of change, which is a normal current change trend under electrochemical reaction. In this case, the second parameter will be smaller.

[0039] calculate The first and second parameters of all intervals, especially when the first... When an interval lies between two segments, 2 cannot be obtained. If statistical analysis is performed on all neighboring intervals, then all current neighboring intervals are directly used for statistical analysis.

[0040] Based on the above explanation, then The first volatility index can be expressed as In the formula, Let K be the first fluctuation index of the nth set of current data, and K be the number of intervals. The first The first and second parameters of each interval. The larger the first and second parameters are, the greater the degree of abnormality of the current response data in the corrosion resistance test, the greater the degree of external interference, the lower the data reliability, and the larger the corresponding first fluctuation index.

[0041] Step 3: Fit the current data of each test group at different potential points to obtain the polarization curves corresponding to the current data of each test group. Based on the similarity between the polarization curves corresponding to the current data of different groups, obtain the second fluctuation index of the current data of each test group.

[0042] Furthermore, the Tafel polarization curves corresponding to the current data of each test group are obtained by fitting the current response signal data of each test group. The method of converting the current response signal data into Tafel polarization curves is an existing technology, and the specific process will not be described in detail.

[0043] Polarization curves essentially represent the electrochemical reaction rate on the working electrode surface as a function of potential, reflecting the corrosion kinetic equilibrium between anodic dissolution and cathodic reduction reactions. Under identical electrolyte parameters, the corrosion reaction mechanism of the workpiece remains consistent. When the surface quality of the tested workpieces is the same, and there are no differences in local microstructural defects leading to abnormal electrochemical corrosion properties, the overall morphology of the polarization curves obtained from different groups of tests shows high similarity, indicating that the electrochemical corrosion kinetics of different tested workpieces are consistent under corrosive environments. Conversely, if there are differences in the coating thickness or uneven distribution of micro-defects on the surface of individual workpieces, making local areas of individual workpieces more sensitive to electrochemical corrosion, abnormal current response occurs overall, causing their polarization curves to deviate significantly from those of other workpieces.

[0044] Based on the above description, a second fluctuation index is constructed by analyzing the similarity between polarization curves of different groups to reflect the consistency characteristics of corrosion kinetics among different groups of data during the test.

[0045] Specifically, the Tafel polarization curve is a function curve with potential as the vertical axis and the logarithm of current density (log(i)) as the horizontal axis, used to quantify the relationship between electrode reaction rate and driving force. The logarithm sequence of current density in the polarization curve corresponding to the nth test group is expressed as follows: , then the first The second fluctuation index of the current data set can be expressed as: ,in It is an exponential function. Let be the cosine similarity.

[0046] Understandably, in data analysis, the cosine similarity between two sequences can represent the similarity between the sequences. In this embodiment, the cosine similarity is calculated... The similarity between them can reflect the consistency characteristics between the two polarization curves, and then statistical analysis is performed on the first... The consistency between the polarization curves of the first set of tests and the polarization curves of all tests is used to reflect the consistency of the polarization curves of the second set of tests. The group tests the degree of anomaly in the polarization curve. Therefore, the smaller the second fluctuation index, the stronger the anomaly. The polarization curves of the first group of tests are similar in morphology to those of most other tests, exhibiting the same corrosion kinetic characteristics. Therefore, the polarization curves of the second group... The lower the abnormality of the test group, the lower the abnormality; conversely, a larger value indicates that the abnormality of the test group is lower. The lower the morphological similarity between the polarization curves of the first test group and those of other tests, the more likely there is external interference or abnormal local coating structure leading to abnormal changes in the corrosion kinetics. The higher the degree of abnormality in the group test.

[0047] Step 4: Construct the reliability of different test group data based on the first and second fluctuation indices of the current data of each test group, and then obtain the contribution weight. Calculate the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece based on the contribution weight, and test the corrosion resistance performance of the hot-dip galvanized workpiece.

[0048] The corrosion potential and corrosion current density of the tested hot-dip galvanized workpieces in each test group were calculated using the Tafel extrapolation method. The Tafel extrapolation method is an existing technology, and the specific process will not be elaborated further. The corrosion potential and corrosion current density of the polarized fine wires corresponding to the group test, obtained by Tafel extrapolation, are denoted as follows: Furthermore, the reliability of the data is constructed based on the first and second fluctuation indices of the current data from each test group. In the formula, To determine the reliability of the nth set of current data, These are the first and second fluctuation indices of the current data in the nth group, respectively, where N is the number of test groups. To avoid extremely small positive numbers with a denominator of zero, this embodiment uses a value of 0.001; Furthermore, obtain the contribution weight: In the formula, The contribution weights for the nth group of current data are defined as follows: The larger the first and second fluctuation indices, the higher the degree of anomaly in that group of tests, and consequently, the lower its reliability. The smaller the value, the more important it is when performing comprehensive calculations. Contribution of corrosion resistance parameters in group tests The lower the value, the better.

[0049] The comprehensive corrosion resistance parameters (comprehensive corrosion potential, comprehensive corrosion current density) of hot-dip galvanized workpieces can then be expressed as: In the formula, The comprehensive corrosion potential of hot-dip galvanized workpieces. The corrosion resistance of hot-dip galvanized workpieces is tested by comprehensively evaluating corrosion current density and other corrosion resistance parameters. In this embodiment, the comprehensive corrosion resistance parameters include comprehensive corrosion potential and comprehensive corrosion current density.

[0050] Based on the same inventive concept as the above method, this application embodiment also provides a corrosion resistance testing system for hot-dip galvanized workpieces, including a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above-described corrosion resistance testing methods for hot-dip galvanized workpieces.

[0051] It is understood that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, the above description focuses on specific embodiments of this specification. Additionally, the processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are possible or may be advantageous.

[0052] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0053] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Any equivalent structural or procedural transformations made based on the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the protection scope of this application.

Claims

1. A method for testing the corrosion resistance of hot-dip galvanized workpieces, characterized in that, Includes the following steps: Current data at different potential points were obtained during the corrosion resistance test of multiple sets of hot-dip galvanized workpieces. The characteristics of current change at different potential points are analyzed to divide the current data of each test group into intervals. The first fluctuation index of the current data of each test group is obtained by using the current stability and the degree of current change in each interval. The polarization curves corresponding to each test group are obtained by fitting the current data at different potential points of each test group. Based on the similarity between the polarization curves corresponding to different test groups, the second fluctuation index of the current data of each test group is obtained. The reliability of the current data of different test groups is constructed based on the first and second fluctuation indices of the current data of each test group, and then the contribution weight is obtained. Based on the contribution weight, the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece are calculated, and the corrosion resistance performance of the hot-dip galvanized workpiece is detected.

2. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 1, characterized in that, Current data for the nth test group The difference sequence is obtained, and the mutation point threshold of the difference sequence is extracted. The potential points corresponding to the data in the difference sequence that exceed the mutation point threshold are used as segmentation point pairs. Divide the data into segments to obtain the intervals.

3. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 1, characterized in that, Before obtaining the first volatility index, for the... The first test group Calculate the interval. The first parameter of each interval : In the formula, It is an exponential function. For the first The average sequence length of each interval and its neighboring intervals For the first The sequence length of the nth interval, where, with the nth interval as the first... Taking the interval as the center, take the left and right sides of it. Each interval is used as its neighborhood interval.

4. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 3, characterized in that, Before obtaining the first volatility index, for the... The first test group Calculate the interval. The second parameter of each interval : ,in To find the maximum value of the function, For the first The rate of change of current in each interval For the first The average rate of change of current in each interval and its neighboring intervals Indicates the first The maximum rate of change of current in each interval and its neighboring intervals. To avoid extremely small positive numbers with a denominator of zero.

5. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 4, characterized in that, The first fluctuation index of the current data for each test group was obtained as follows: In the formula, Let K be the first fluctuation index of the nth set of current data, and K be the number of intervals. The first The first and second parameters of each interval are given, where if K is less than a preset value, the first fluctuation index is zero.

6. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 1, characterized in that, The process for obtaining the second fluctuation index of the current data for each test group is as follows: ,in, This is the first fluctuation index of the nth set of current data. It is an exponential function. Let N be the cosine similarity, and N be the number of test groups. These are the logarithmic sequences of current densities in the polarization curves corresponding to the nth and mth test groups, respectively.

7. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 1, characterized in that, The specific method for obtaining the reliability of the data from different test groups is as follows: In the formula, To determine the reliability of the nth set of current data, These are the first and second fluctuation indices of the current data in the nth group, respectively, where N is the number of test groups. To avoid extremely small positive numbers with a denominator of zero.

8. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 7, characterized in that, The contribution weight is obtained as follows: In the formula, The contribution weight for the nth group of current data.

9. The method for testing the corrosion resistance of hot-dip galvanized workpieces as described in claim 8, characterized in that, The process for obtaining the comprehensive corrosion resistance parameters of the hot-dip galvanized workpiece is as follows: The corrosion potential and corrosion current density of the hot-dip galvanized workpieces tested in each test group were calculated using the Tafel extrapolation method. The overall corrosion potential of the hot-dip galvanized workpiece was then determined. Comprehensive corrosion current density They are respectively: Among them, the first The corrosion potential and corrosion current density of the polarized fine wires corresponding to the group test were obtained by Tafel extrapolation. .

10. A system for testing the corrosion resistance of hot-dip galvanized workpieces, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method for testing the corrosion resistance of hot-dip galvanized workpieces as described in any one of claims 1-9.

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