Method and system for testing tensile stress relaxation of copper and copper alloy strip and foil materials

Abstract

The present application relates to the technical field of copper material testing, and specifically discloses a copper and copper alloy strip and foil material tensile stress relaxation testing method and system. The present application takes double photos of copper and copper alloy strip and foil material samples, identifies and matches corresponding testing metadata; performs testing calibration and environmental control; controls tensile loading of the copper and copper alloy strip and foil material samples; collects synchronous testing data, and performs abnormal elimination and index calculation on the synchronous testing data; generates a stress relaxation curve according to the synchronous index data, compares it with a corresponding standard relaxation curve, and generates a relaxation testing report. The present application can match testing metadata, perform automatic testing calibration, environmental control, tensile loading control, data processing and testing report generation, realize automatic testing and correct evaluation of copper and copper alloy strip and foil material tensile stress relaxation, promote deeper research and development of high-end connectors and precision connectors and other materials, and improve production level.

Description

Technical Field

[0001] This invention belongs to the field of testing technology for copper and copper alloy strips and foils, and particularly relates to a method and system for testing tensile stress relaxation of copper and copper alloy strips and foils. Background Technology

[0002] Testing of copper and copper alloy strips and foils is a process of conducting physical, mechanical, and surface property tests and evaluations on strip metal materials made primarily of copper and its alloys. The aim is to comprehensively reflect the quality stability and applicability of the strips and foils under different application conditions, including mechanical indicators such as tensile strength, yield strength, elongation, hardness, fatigue performance, and stress relaxation characteristics, as well as material properties such as surface flatness, thickness uniformity, grain size, conductivity, and corrosion resistance.

[0003] Stress relaxation refers to the phenomenon that the stress in a metallic material decreases over time under specified temperature and constant initial deformation or displacement. However, due to a long-standing lack of understanding of the importance of stress relaxation resistance in copper and copper alloy strips and foils, there is a lack of systematic research on stress relaxation testing methods in existing technologies. This directly hinders the accurate evaluation of the performance of copper and copper alloy strips and foils, resulting in a lack of tensile relaxation performance data for reference and application during product design and material selection. This limits in-depth research and development of materials for high-end connectors and precision fittings, making it difficult to improve production levels. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for testing tensile stress relaxation of copper and copper alloy strips and foils, aiming to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions: A method for tensile stress relaxation testing of copper and copper alloy strips and foils, the method specifically includes the following steps: Binocular imaging was performed on copper and copper alloy strip and foil samples to acquire binocular imaging data, which was then identified to obtain sample feature data and matched with corresponding test metadata. Perform testing, calibration, and environmental control to determine whether the testing conditions are met, and pre-treat the copper and copper alloy strip and foil samples when the testing conditions are met. According to the aforementioned test metadata, tensile loading control was applied to the copper and copper alloy strip and foil samples. Synchronous test data is collected according to a preset sampling frequency, and anomaly removal and index calculation are performed on the synchronous test data to obtain synchronous index data. Based on the synchronous index data, a stress relaxation curve is generated and compared with the corresponding standard relaxation curve to generate a relaxation test report.

[0006] This invention also provides a tensile stress relaxation testing system for copper and copper alloy strips and foils. The system includes a binocular imaging and recognition unit, a test calibration and environmental control unit, a tensile loading control unit, a test index calculation unit, and a test report generation unit, wherein: The binocular imaging and recognition unit is used to perform binocular imaging on copper and copper alloy strip and foil samples, acquire binocular imaging data, and perform recognition to obtain sample feature data and match the corresponding test metadata. The test calibration and environment control unit is used to perform test calibration and environmental control, determine whether the test conditions are met, and pre-treat the copper and copper alloy strip foil samples when the test conditions are met. A tensile loading control unit is used to control the tensile loading of the copper and copper alloy strip and foil samples according to the test metadata. The test index calculation unit is used to collect synchronous test data according to a preset sampling frequency, and to perform anomaly removal and index calculation on the synchronous test data to obtain synchronous index data. The test report generation unit is used to generate a stress relaxation curve based on the synchronous index data, compare it with the corresponding standard relaxation curve, and generate a relaxation test report.

[0007] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention establishes a multi-level data verification and repair mechanism, divides synchronous test data into time windows and performs benchmark statistical comparison, combines material physics rules to perform secondary verification and intelligent removal of abnormal data, and introduces dynamic compensation of environmental parameters and time-domain consistency analysis to achieve full-process deep purification of effective test data. This greatly ensures the authenticity and consistency of the calculation data of core indicators such as initial stress, real-time stress, stable stress and relaxation rate, and lays a solid and reliable data foundation for the accurate evaluation of stress relaxation performance. 2. This invention uses segmented polymer stress data and accurately identifies characteristic positions such as accelerated relaxation inflection points and steady-state starting points. It employs a phased high-precision fitting strategy to generate continuous curves and integrates environmental parameter inverse compensation and oscillation suppression processing to ultimately generate high-fidelity stress relaxation curves that can completely preserve the intrinsic characteristics of the material in the three stages of accelerated relaxation, main relaxation, and steady-state. This significantly improves the accuracy and reliability of the curves in characterizing the true relaxation behavior of the material. 3. This invention calculates the segmented stress difference and determines compliance by aligning the feature point sequence of the test curve and the standard curve. It also introduces a dynamic weighting coefficient based on the material usage scenario to assess the severity of the out-of-tolerance section, and finally achieves a comprehensive weighted judgment of the sample's qualification. This method makes the qualification judgment process more scientific and rigorous, and can not only give an overall conclusion but also accurately locate the location and degree of defects, greatly improving the intelligence level and decision support capability of product quality evaluation. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention.

[0009] Figure 1 A flowchart of the method provided by an embodiment of the present invention is shown.

[0010] Figure 2 An application architecture diagram of the system provided in an embodiment of the present invention is shown. Detailed Implementation

[0011] 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.

[0012] As is understandable, stress relaxation refers to the phenomenon that the stress in a metallic material decreases over time under specified temperature and constant initial deformation or displacement. However, due to a long-standing lack of understanding of the importance of stress relaxation resistance in copper and copper alloy strips and foils, there is a lack of systematic research on stress relaxation testing methods in existing technologies. This directly hinders the accurate evaluation of the performance of copper and copper alloy strips and foils, resulting in a lack of tensile relaxation performance data for reference and application during product design and material selection. This limits in-depth research and development of materials for high-end connectors and precision fittings, making it difficult to improve production levels.

[0013] To address the aforementioned issues, this invention employs binocular imaging of copper and copper alloy strip / foil samples to acquire binocular imaging data, which is then identified to obtain sample feature data and matched with corresponding test metadata. Test calibration and environmental control are performed to determine if test conditions are met, and if so, the copper and copper alloy strip / foil samples are pre-processed. Tensile loading control is applied to the copper and copper alloy strip / foil samples according to the test metadata. Synchronous test data is collected at a preset sampling frequency, and anomalies are removed and indexes are calculated to obtain synchronous index data. Based on the synchronous index data, a stress relaxation curve is generated and compared with a corresponding standard relaxation curve to generate a relaxation test report. This system can automatically match test metadata, perform test calibration, environmental control, tensile loading control, data processing, and test report generation, achieving automatic testing and accurate evaluation of tensile stress relaxation in copper and copper alloy strip / foil materials. This can promote deeper research and development of materials for high-end connectors and precision connectors, and improve production levels.

[0014] Figure 1 A flowchart of the method provided by an embodiment of the present invention is shown.

[0015] Specifically, a method for testing tensile stress relaxation of copper and copper alloy strips and foils includes the following steps: Step S101: Perform binocular imaging on copper and copper alloy strip and foil samples, acquire binocular imaging data, identify the sample feature data, and match the corresponding test metadata.

[0016] In this embodiment of the invention, according to multiple preset binocular shooting angles and corresponding binocular shooting parameters, the copper and copper alloy strip and foil samples fed to the target area are subjected to binocular shooting to obtain binocular shooting data. Then, the length, width and thickness of the binocular shooting data are identified and recorded to obtain sample feature data of the copper and copper alloy strip and foil samples. After that, according to the sample feature data, the strip and foil sample type of the copper and copper alloy strip and foil samples is matched from a preset feature database. Then, according to the strip and foil sample type, the test metadata of the copper and copper alloy strip and foil samples is matched from a preset metadata database.

[0017] It should be noted that the aforementioned test metadata refers to a pre-configured parameter package or parameter library for tensile stress relaxation testing of copper and copper alloy strips and foils, containing all control parameters and judgment criteria required to complete a full test. Specifically, the test metadata includes, but is not limited to: prestress magnitude, prestress loading time, holding time before initial stress loading, holding temperature after initial stress loading, holding time after loading, tensile rate, target strain, target value for ambient temperature control, target value for ambient humidity control, sampling frequency, and standard relaxation curve data.

[0018] Wherein, the magnitude of the prestress is the magnitude of the preload force applied to the sample; the prestress loading time is the duration of the preload force applied; the initial stress loading preheating time is the heat preservation time required for the sample to reach thermal equilibrium at the test temperature before applying the initial stress; the initial stress loading postheating temperature is the control temperature of the environmental chamber or environmental cabin after entering the constant strain holding state; and the loading postheating time is the total duration of maintaining the test temperature under the constant strain holding state.

[0019] It should be further noted that the configuration of the environmental humidity control target value is related to the test scenario: when the test scenario is room temperature tensile stress relaxation, the humidity control target value is set as an active adjustment parameter, and the system adjusts the humidity of the laboratory environment according to the target value; when the test scenario is high temperature tensile stress relaxation using an environmental chamber for heating (e.g., 150°C), the humidity control target value is set as a monitoring mode parameter, that is, the system only monitors the actual relative humidity state inside the environmental chamber through a humidity sensor to determine whether the environmental chamber's sealing has failed, and does not use it as a control target for actively adjusting to a specific non-zero value.

[0020] In addition, in the high-temperature environment chamber test scenario, the humidity correction step for tensile strength in subsequent steps is automatically skipped, and the humidity data is only used for sealing performance determination; only in the room temperature test scenario, the humidity data is involved in the calculation of tensile strength correction.

[0021] In a preferred embodiment of the present invention, the step of performing binocular imaging on copper and copper alloy strip / foil samples, acquiring binocular imaging data, identifying the sample feature data, and matching the corresponding test metadata specifically includes the following steps: Step S1011: Perform binocular imaging on the copper and copper alloy strip and foil samples to obtain binocular imaging data; Step S1012: Length, width, and thickness of the binocular imaging data are identified and recorded to obtain sample feature data; It should be noted that the identification of length, width, and thickness in the binocular imaging data specifically includes the identification of the overall dimensions of the sample and the identification of the geometric parameters of the working area of ​​the specimen. The length, width, and thickness refer to the overall dimensions of the copper and copper alloy strip / foil samples, used to match fixture specifications and loading ranges. The geometric parameters of the specimen working area include parallel width, parallel length, original gauge length, and transition arc radius. These parameters are the specific dimensions of the gauge length segment of the specimen identified by binocular vision, used for accurate strain calculation and normalization measurement of the stress relaxation curve. The sample characteristic data is jointly constituted by the overall dimensions of the sample and the geometric parameters of the specimen working area.

[0022] Step S1013: Match the corresponding foil sample type based on the sample feature data; Step S1014: Match the corresponding test metadata according to the type of the foil sample.

[0023] Furthermore, the tensile stress relaxation test method for copper and copper alloy strips and foils also includes the following steps: Step S102: Perform test calibration and environmental control to determine whether the test conditions are met, and if the test conditions are met, pre-treat the copper and copper alloy strip foil samples.

[0024] In this embodiment of the invention, force sensing zero-point calibration and displacement range calibration are performed on copper and copper alloy strip / foil samples, and the calibration data is recorded. The calibration data is then compared with historical data to determine whether the deviation of force sensing zero-point calibration or displacement range calibration is greater than the corresponding maximum value in the historical data. When the deviations of force sensing zero-point calibration and displacement range calibration are not greater than the corresponding maximum values ​​in the historical data, the deviation is determined to be within limits. At this time, according to the test metadata, temperature and humidity are controlled and real-time environmental monitoring is performed to determine whether the environmental conditions are met. When the temperature and humidity values ​​meet the corresponding values ​​in the test metadata, the environmental conditions are determined to be met. At this time, a preload force is applied to the copper and copper alloy strip / foil samples to eliminate the contact gaps of the copper and copper alloy strip / foil samples.

[0025] In a preferred embodiment of the present invention, the step of performing test calibration and environmental control to determine whether the test conditions are met, and pre-treating the copper and copper alloy strip / foil samples when the test conditions are met, specifically includes the following steps: Step S1021: Perform force sensing zero-point calibration and displacement range calibration, and record the calibration data; Step S1022: Compare the calibration data with historical data to determine whether the deviation exceeds the limit; Step S1023: When the deviation is within limits, perform temperature and humidity control according to the test metadata and determine whether the environmental conditions are met; wherein, determining whether the environmental conditions are met specifically includes: for the temperature control target value, comparing the real-time monitored temperature value with the temperature target value in the test metadata to determine whether the deviation is within the allowable range; for the humidity control target value, performing differentiated judgment according to the test scenario, when the test scenario is room temperature tensile stress relaxation, comparing the real-time monitored humidity value with the humidity target value in the test metadata to determine whether the humidity control requirements are met; When the test scenario involves high-temperature tensile stress relaxation using an environmental chamber for heating, the humidity control target value is set to monitoring mode. The system uses real-time monitored humidity data to determine whether the environmental chamber's seal has failed, rather than comparing it with a specific humidity value for proactive adjustment. This differentiated judgment strategy ensures the rationality and effectiveness of environmental condition determination under different test scenarios.

[0026] Step S1024: After the environmental conditions are met, a preload force is applied to the copper and copper alloy strip / foil sample.

[0027] It should be noted that the "environmental conditions" mentioned in this invention refer to the temperature and humidity of the microenvironment in which the copper and copper alloy foil samples are located during the testing process. Specifically, depending on the testing scenario, the environmental conditions include the following two situations: (1) When the sample is heated using an environmental chamber or environmental cabin (e.g., a high-temperature stress relaxation test at a test temperature of 150°C), the environmental conditions refer to the temperature and humidity inside the environmental chamber or environmental cabin. The ambient temperature and humidity of the laboratory are only used as a reference background value for the normal operation of the environmental chamber and are not directly used as the test environmental conditions of the sample; (2) When a tensile stress relaxation test is performed at room temperature, the environmental conditions refer to the ambient temperature and humidity of the laboratory. In this case, the ambient environment of the laboratory is the direct test environmental conditions of the sample.

[0028] This invention pre-configures target values ​​for environmental conditions (target temperature and target humidity) using test metadata. During testing, temperature and humidity sensors monitor actual environmental conditions in real time, comparing the monitored values ​​with the target values ​​to determine if the required environmental conditions for the test are met. When environmental conditions exceed the allowable deviation range, the system automatically adjusts the environment or issues a prompt to ensure the test is conducted under the specified environmental conditions.

[0029] Furthermore, in subsequent steps, when performing reverse compensation for periods of abrupt changes in environmental parameters, the system only uses the parameter changes in the actual microenvironment of the sample (the interior of the environmental chamber or the laboratory air directly in contact with the sample) as the basis for stress value compensation. Parameter fluctuations in the laboratory's macro-environment (such as brief changes in laboratory temperature caused by personnel entering and exiting) do not directly participate in the reverse compensation calculation of stress values.

[0030] Furthermore, the tensile stress relaxation test method for copper and copper alloy strips and foils also includes the following steps: Step S103: Perform tensile loading control on the copper and copper alloy strip / foil samples according to the test metadata.

[0031] In this embodiment of the invention, the stretching rate and target strain are determined according to the test metadata. Then, the stretching control of copper and copper alloy strip and foil samples is performed according to the stretching rate, and real-time stretching monitoring is carried out to obtain the real-time stretching amount. At the same time, the real-time strain is calculated based on the real-time stretching amount, and the real-time strain is compared with the target strain. When the real-time strain reaches the target strain, a constant strain is maintained.

[0032] Understandably, dividing the real-time stretch by the initial length yields the real-time strain.

[0033] In a preferred embodiment of the present invention, the tensile loading control of the copper and copper alloy strip / foil samples according to the test metadata specifically includes the following steps: Step S1031: Determine the tensile rate and target strain according to the test metadata; Step S1032: According to the stretching rate, the copper and copper alloy strip and foil samples are stretched and controlled, and the real-time stretching amount is determined. Step S1033: Calculate the real-time strain based on the real-time tensile amount; Step S1034: When the real-time strain reaches the target strain, a constant strain is maintained.

[0034] Furthermore, the tensile stress relaxation test method for copper and copper alloy strips and foils also includes the following steps: Step S104: Collect synchronous test data according to the preset sampling frequency, and perform anomaly removal and index calculation on the synchronous test data to obtain synchronous index data.

[0035] In this embodiment of the invention, synchronous test data including sampling time, real-time tensile amount, temperature, humidity and clamping force are collected according to a preset sampling frequency. Anomalies such as numerical mutations in the synchronous test data are identified and the identified abnormal data are removed to achieve effective optimization of the synchronous test data and obtain valid test data. Then, based on the valid test data, index calculations are performed to obtain synchronous index data including initial stress, real-time stress, stable stress and relaxation rate.

[0036] Understandably, the real-time clamping force is divided by the cross-sectional area of ​​the copper and copper alloy strip / foil sample to obtain the real-time stress.

[0037] In a preferred embodiment of the present invention, the step of collecting synchronous test data at a preset sampling frequency and performing anomaly removal and index calculation on the synchronous test data to obtain synchronous index data specifically includes the following steps: Step S1041: Collect synchronous test data according to the preset sampling frequency. The synchronous test data includes sampling time, real-time tensile amount, temperature, humidity and clamping force. Preferably, the sampling frequency is set in segments according to the total test duration. Specifically: during the tensile loading control stage, a first sampling frequency of 10Hz to 100Hz is used to fully capture the transient changes in stress with strain during the loading process; during the initial relaxation stage after entering the constant strain holding state, a second sampling frequency of 1Hz to 10Hz is used to finely record the curve shape of the rapid stress decay stage. In the middle and later stages of the constant strain holding state, a third sampling frequency of 0.01Hz to 0.1Hz (i.e., sampling once every 10 to 100 seconds) is used for long-term steady-state monitoring. The total number of data collected during the entire test process does not exceed a preset data total threshold. When the accumulated total exceeds the preset threshold, the system automatically issues a prompt to the user or automatically reduces the sampling frequency in the middle and later stages to avoid data storage overflow or performance degradation of the test system due to long-term high-frequency sampling.

[0038] More preferably, when performing relaxation rate calculations (i.e., dividing the calculation window into equal-duration windows), the duration of the equal-duration calculation window should be dynamically determined based on the current sampling frequency. Specifically, the duration of the calculation window should be no less than three times the sampling interval corresponding to the current sampling frequency, to ensure that each calculation window contains at least three valid data points for rate fitting; when the sampling frequency is switched to a lower frequency, the system automatically increases the calculation window duration proportionally to ensure the statistical validity of the relaxation rate calculation.

[0039] Step S1042: Perform anomaly identification and removal processing on the synchronous test data to obtain valid test data; Step S1043: Based on the valid test data, perform index calculations to obtain synchronous index data, which includes initial stress, real-time stress, stable stress, and relaxation rate.

[0040] In a preferred embodiment of the present invention, the step of identifying and removing numerical mutations in the synchronous test data to obtain valid test data specifically includes the following steps: Step S10421: Divide the synchronous test data into continuous data segments according to a preset time window, and independently calculate the baseline statistical values ​​of each parameter for each data segment. The baseline statistical values ​​include the arithmetic mean, standard deviation, and the mean of the rate of change of adjacent sampling points. Step S10422: Compare the real-time data of each parameter in the synchronous test data with the baseline statistical value of the data segment to which the parameter belongs: If a single point of data deviates from the arithmetic mean by more than a preset dispersion threshold (the deviation of a single point value from the arithmetic mean by more than 3 times the standard deviation), it is marked as an isolated outlier; if the rate of change of two consecutive points of data exceeds the baseline change trend range (not exceeding 5 times the mean of the rate of change of adjacent sampling points), it is marked as a continuous abrupt change point; if the environmental parameter exceeds the allowable range of the test metadata, it is marked as an environmental failure point, and the marking results are associated to generate an anomaly type mark set; the environmental parameters include temperature and humidity; Step S10423: Establish physical rules based on the stress-strain relationship of copper and copper alloy strips and foils: verify the rationality of clamping force fluctuations based on real-time tensile changes, and verify the continuity of environmental parameter changes based on historical temperature and humidity trends; substitute the anomaly type marker set into the physical rules for secondary verification: if the clamping force mutation point does not correspond to a reasonable tensile change, confirm that the point is an equipment interference anomaly; if the environmental parameter mutation point does not show continuous change characteristics, confirm that the point is a sensor distortion anomaly, so as to obtain the final anomaly point location set; Step S10424: Remove all abnormal data points from the final set of abnormal points to generate a data sequence with null values. Use a differentiated repair strategy to fill the null values: use linear interpolation of adjacent data to fill isolated null values, and use the moving average of adjacent data segments to fill continuous null value segments to obtain the repaired data sequence. Step S10425: Identify the segments in the repair data sequence where environmental parameters have undergone non-abrupt drift, and dynamically compensate the real-time stretching amount and clamping force of the segments where environmental parameters have undergone non-abrupt drift to obtain an environmental coupling compensation dataset; the dynamic compensation includes: compensating the clamping force according to a preset ratio when the temperature continues to shift, and correcting the stretching amount according to the material properties when the humidity continues to shift.

[0041] Step S10426: Perform temporal consistency analysis on the environmental coupling compensation dataset: If the parameter feature quantity undergoes a jump without environmental support between adjacent data segments, it is determined to be a hidden abnormal segment. Apply dynamic smoothing processing based on feature quantity changes to the data of this segment to obtain the re-verification dataset. Step S10427: Reassemble the re-verification dataset according to the original time sequence, remove the original data corresponding to all outliers, and retain the valid data points that have passed the full process verification to obtain valid test data.

[0042] It is important to note that the tensile stress relaxation curves of copper and copper alloy strips and foils under constant strain conditions exhibit typical staged characteristics: the curve initially rises to the stress peak with tensile loading, then enters a rapid decline phase, after which the rate of decline gradually slows down and tends to flatten. This rapid decline phase is an intrinsic manifestation of the material's stress relaxation behavior; although the rate of stress change is relatively large, it exhibits a monotonically decreasing trend and conforms to the exponential decay characteristics of stress relaxation in copper alloys.

[0043] Therefore, when determining anomalies in the rate of change of two consecutive data points, the following exemption rule is added: If the current continuous data segment is located after the stress peak point after the tensile loading is completed, and the data change trend shows a monotonically decreasing trend and conforms to the exponential decay characteristics of stress relaxation in copper alloys, then the "continuous abrupt change point" marking rule does not apply to this data segment. The system only marks isolated abrupt change points whose rate of change exceeds 10 times the average rate of change of this segment as anomalies. Through the above exemption rule, it is ensured that anomaly identification and rejection processing only targets false data points introduced by non-material intrinsic factors such as equipment noise, occasional sensor failures, and electromagnetic interference, and will not mistakenly delete data in the inherent rapid decline phase of the stress relaxation curve.

[0044] The purpose of collecting humidity data in this invention is twofold: First, in the scenario of room temperature tensile stress relaxation testing, fluctuations in laboratory ambient humidity may interfere with the clamping force measurement by affecting the sample surface condition or fixture contact conditions. In this case, humidity data serves as an auxiliary basis for anomaly identification. Second, in the scenario of high-temperature environmental chamber testing, humidity data is mainly used to monitor the sealing and working status of the environmental chamber and to determine whether there is a risk of moisture intrusion.

[0045] To achieve the above objectives, when dynamically compensating for real-time tensile strength and clamping force in sections where environmental parameters experience non-abrupt drift, a differentiated compensation strategy is implemented based on the test scenario: if the current test scenario is at room temperature and humidity continuously shifts, the tensile strength is corrected for humidity according to material properties; if the current test scenario is in a high-temperature environmental chamber, the humidity correction step for tensile strength is skipped, and humidity data is only used for sealing performance assessment and does not participate in the numerical compensation of mechanical parameters. This differentiated strategy avoids introducing invalid humidity compensation calculations in high-temperature test scenarios while ensuring data accuracy in room-temperature test scenarios.

[0046] In a preferred embodiment of the present invention, the step of calculating the index based on the valid test data and obtaining the synchronous index data specifically includes the following steps: Step S10431: Traverse the valid test data, identify the starting time point when the tensile loading control stage ends and enters the constant strain holding state, extract the clamping force data corresponding to the time point, calculate the initial stress value by combining it with the real-time cross-sectional area in the sample feature data, and record the corresponding sampling time as the initial stress timestamp to obtain the initial stress data containing the initial stress value and the initial stress timestamp. Step S10432: Extract the clamping force data corresponding to all sampling time points after the initial stress timestamp, and perform continuous calculations in combination with the real-time cross-sectional area in the sample feature data to generate a real-time stress data sequence that corresponds one-to-one with each sampling time point, so as to obtain a real-time stress dataset. Step S10433: Perform stationarity analysis on the real-time stress dataset, identify the continuous time period in which the stress change rate is continuously lower than the preset stability threshold, extract the arithmetic mean of all real-time stress data within the time period as the stable stress value, and record the starting time of the time period as the stability start time. Step S10434: Divide the time from the initial stress timestamp to the stable start time into multiple equal-duration calculation windows. For the real-time stress data sequence in each calculation window, calculate the ratio of its stress decay to the corresponding duration to obtain the relaxation rate sequence corresponding to multiple calculation windows. Step S10435: Integrate the initial stress data, real-time stress dataset, stable stress values ​​and their stable start time, and relaxation rate sequence, align and correlate them according to the sampling time, and generate a structured index set containing time dimension correspondence to obtain a preliminary synchronization index dataset. Step S10436: Perform integrity verification and timing consistency verification on the preliminary synchronization index dataset, and remove redundant or conflicting entries caused by alignment to obtain the synchronization index data.

[0047] In this embodiment of the invention, by establishing a multi-level data verification and repair mechanism, synchronous test data is divided into time windows and compared with benchmark statistics. Abnormal data is then verified and intelligently removed by combining material physics rules. Furthermore, dynamic compensation of environmental parameters and time-domain consistency analysis are introduced to achieve in-depth purification of the entire process of valid test data. This greatly ensures the authenticity and consistency of the calculation data of core indicators such as initial stress, real-time stress, stable stress, and relaxation rate, laying a solid and reliable data foundation for the accurate evaluation of stress relaxation performance.

[0048] Furthermore, the tensile stress relaxation test method for copper and copper alloy strips and foils also includes the following steps: Step S105: Based on the synchronization index data, generate a stress relaxation curve and compare it with the corresponding standard relaxation curve to generate a relaxation test report.

[0049] In this embodiment of the invention, a stress relaxation curve is generated based on the synchronous index data, and a standard relaxation curve is matched based on the test metadata. By comparing the stress relaxation curve with the standard relaxation curve, the degree of fit between the stress relaxation curve and the standard relaxation curve is identified, and it is determined whether the copper and copper alloy strip and foil samples are qualified. Qualification judgment information is obtained, and then the sample characteristic data, synchronous index data, stress relaxation curve, and qualification judgment information are filled in and organized according to the preset standard report format to generate a relaxation test report for the copper and copper alloy strip and foil samples.

[0050] In a preferred embodiment of the present invention, the step of generating a stress relaxation curve based on the synchronization index data and comparing it with the corresponding standard relaxation curve to generate a relaxation test report specifically includes the following steps: Step S1051: Generate a stress relaxation curve based on the synchronization index data; Step S1052: Match a standard relaxation curve based on the test metadata; Step S1053: Compare the stress relaxation curve with the standard relaxation curve to determine whether the copper and copper alloy strip and foil sample is qualified and obtain the qualification judgment information; Step S1054: Generate a relaxation test report based on the sample characteristic data, the synchronization index data, the stress relaxation curve, and the pass / fail judgment information.

[0051] In a preferred embodiment of the present invention, generating a stress relaxation curve based on the synchronization index data specifically includes the following steps: Step S10511: Extract the real-time stress and corresponding sampling time from the synchronous index data, and divide the data into continuous time periods according to the preset duration; aggregate the stress data independently for each time period to generate a segmented aggregated dataset containing the average stress at the beginning of the time period, the stress extreme value within the time period, and the stress attenuation at the end of the time period. Step S10512: Traverse the segmented aggregated dataset to identify stress change characteristics: when the stress attenuation within a time period exceeds a preset change threshold (15%), it is marked as an accelerated relaxation inflection point; when the deviation between the stress value at the end of the time period and the average stress value at the beginning of the next time period is less than a preset tolerance (0.5%), it is marked as the starting point of the steady state; the segment with the largest span between adjacent accelerated relaxation inflection points is designated as the main relaxation stage to obtain an aggregated dataset with inflection point markings; Step S10513: Based on the aggregated dataset with inflection point markings, a high-precision fitting strategy is used to generate a continuous curve for the main relaxation phase; initial stress constraint fitting is used for the segment before the inflection point of accelerated relaxation; asymptotic convergence fitting is used for the segment after the steady-state starting point; and a smooth transition processing is applied at the inflection point connection to eliminate step abrupt changes in order to obtain the fitted curve segment. Step S10514: Extract temperature and humidity records from the synchronous index data, identify the segments in the fitted curve that overlap with the periods of sudden changes in environmental parameters; based on the environmental sensitivity parameters of the material in the test metadata, perform reverse compensation on the stress values ​​of the overlapping segments: when the temperature rises, adjust the stress values ​​upward according to a preset ratio, and when the humidity is abnormal, adjust the stress values ​​downward according to the material's hygroscopic characteristics, so as to obtain the environmentally compensated curve. Step S10515: Scan the stress change rate of the curve after environmental compensation, identify the oscillation segment where the frequency of alternating positive and negative changes exceeds a preset threshold (5Hz); generate a reference envelope based on the stress change trend of adjacent non-oscillation segments, constrain the oscillation segment data to the range of the reference envelope, retain trend characteristics and suppress high-frequency fluctuations to obtain a continuous curve after oscillation suppression. Step S10516: The continuous curves after oscillation suppression are spliced ​​along the time axis, and the marked inflection point position information is inserted to generate a stress relaxation curve; the stress relaxation curve completely retains the characteristics of the three stages of accelerated relaxation, main relaxation and steady state, and the data point density meets the requirements of relaxation rate calculation accuracy.

[0052] In this embodiment of the invention, by segmenting the aggregated stress data and accurately identifying characteristic positions such as the inflection point of accelerated relaxation and the starting point of the steady state, a staged high-precision fitting strategy is adopted to generate a continuous curve. In addition, environmental parameter inverse compensation and oscillation suppression processing are integrated to finally generate a high-fidelity stress relaxation curve that can completely retain the intrinsic characteristics of the material in the three stages of accelerated relaxation, main relaxation and steady state. This significantly improves the accuracy and reliability of the curve in characterizing the true relaxation behavior of the material.

[0053] In a preferred embodiment of the present invention, comparing the stress relaxation curve with the standard relaxation curve to determine whether the copper and copper alloy strip / foil sample is qualified, and obtaining qualification information specifically includes the following steps: Step S10531: Extract the feature point set from the stress relaxation curve and the standard relaxation curve. The feature point set includes the initial stress point, the starting point of the main relaxation stage, the inflection point position, and the stable stress convergence point. Use the dynamic time warping algorithm to perform time-series alignment of the feature point set of the stress relaxation curve and the standard relaxation curve to obtain the aligned feature point sequence. Step S10532: Based on the aligned feature point sequence, calculate the stress difference between the stress relaxation curve and the standard relaxation curve at each stage, and statistically analyze the maximum deviation, average deviation, and deviation change trend to obtain a set of segmented difference indices. Step S10533: Based on the predefined tolerance allowable range in the test metadata, the compliance of the segment difference index set is determined. If the stress difference value of a certain stage exceeds the tolerance limit, it is marked as an out-of-tolerance segment, and the duration and magnitude of the out-of-tolerance are recorded to obtain the out-of-tolerance marking result set. Step S10534: Integrate the segmented difference index set and the out-of-tolerance label result set, introduce the material use scenario weight coefficient, and conduct a severity level assessment of the out-of-tolerance segment. If the out-of-tolerance occurs in the initial stage, it is assigned a higher weight; if it occurs in the stable stage, it is assigned a lower weight, so as to obtain the weighted out-of-tolerance assessment result. Step S10535: Based on the weighted out-of-tolerance evaluation results, determine whether the sample is qualified: if the weighted evaluation results of all out-of-tolerance sections do not exceed the preset tolerance threshold, the sample is qualified; if the weighted evaluation result of any out-of-tolerance section exceeds the tolerance threshold, the sample is unqualified, and generate defect description information including out-of-tolerance location, out-of-tolerance magnitude, and duration; combine the qualified judgment conclusion and the defect description information to generate qualified judgment information.

[0054] In this embodiment of the invention, by aligning the feature point sequences of the test curve and the standard curve, segmented stress difference calculation and compliance determination are performed. A dynamic weighting coefficient based on the material usage scenario is introduced to assess the severity level of the out-of-tolerance section, and finally, a comprehensive weighted judgment of the sample's qualification is achieved. This method makes the qualification determination process more scientific and rigorous, and can not only give an overall conclusion but also accurately locate the location and extent of defects, greatly improving the intelligence level and decision support capability of product quality evaluation.

[0055] Furthermore, Figure 2 An application architecture diagram of the system provided in an embodiment of the present invention is shown.

[0056] In another preferred embodiment of the present invention, a tensile stress relaxation testing system for copper and copper alloy strips and foils includes: The binocular imaging and recognition unit 101 is used to perform binocular imaging on copper and copper alloy strip and foil samples, acquire binocular imaging data, and perform recognition to obtain sample feature data and match corresponding test metadata.

[0057] In this embodiment of the invention, the binocular imaging and recognition unit 101 performs binocular imaging on the copper and copper alloy strip and foil samples fed to the target area according to a preset multiple binocular imaging angles and corresponding multiple binocular imaging parameters, acquires binocular imaging data, then identifies the length, width and thickness of the binocular imaging data, records the data, and acquires the sample feature data of the copper and copper alloy strip and foil samples. Then, based on the sample feature data, it matches the strip sample type of the copper and copper alloy strip and foil samples from a preset feature database, and then matches the test metadata of the copper and copper alloy strip and foil samples from a preset metadata database based on the strip sample type.

[0058] In a preferred embodiment provided by the present invention, the binocular imaging and recognition unit 101 specifically includes: The binocular imaging module 1011 is used to perform binocular imaging on copper and copper alloy strip and foil samples to acquire binocular imaging data. The identification and recording module 1012 is used to identify the length, width and thickness of the binocular imaging data, record the data, and obtain sample feature data. The foil sample type matching module 1013 is used to match the corresponding foil sample type based on the sample feature data; The test metadata matching module 1014 is used to match the corresponding test metadata according to the type of the foil sample.

[0059] Furthermore, the tensile stress relaxation testing system for copper and copper alloy strips and foils also includes: The test calibration and environment control unit 102 is used to perform test calibration and environmental control, determine whether the test conditions are met, and pre-treat the copper and copper alloy strip foil samples when the test conditions are met.

[0060] In this embodiment of the invention, the test calibration and environmental control unit 102 performs force sensing zero-point calibration and displacement range calibration on the copper and copper alloy strip foil samples, records the calibration data, and then compares the calibration data with historical data to determine whether the deviation of the force sensing zero-point calibration or displacement range calibration is greater than the corresponding maximum value in the historical data. When the deviations of both the force sensing zero-point calibration and displacement range calibration are not greater than the corresponding maximum values ​​in the historical data, it is determined that the deviation is within the limit. At this time, according to the test metadata, the temperature and humidity environment is controlled and real-time environmental monitoring is performed to determine whether the environmental conditions are met. When the temperature and humidity values ​​meet the corresponding values ​​in the test metadata, it is determined that the environmental conditions are met. At this time, a preload force is applied to the copper and copper alloy strip foil samples to eliminate the contact gaps of the copper and copper alloy strip foil samples.

[0061] In a preferred embodiment of the present invention, the test calibration and environment control unit 102 specifically includes: The calibration recording module 1021 is used to perform force sensing zero-point calibration and displacement range calibration, and to record the calibration data. The data comparison module 1022 is used to compare the correction and calibration data with historical data to determine whether the deviation exceeds the limit; The environmental control module 1023 is used to control the temperature and humidity according to the test metadata when the deviation does not exceed the limit, and to determine whether the environmental conditions are met. The preload force application module 1024 is used to apply a preload force to the copper and copper alloy strip foil sample after environmental conditions are met.

[0062] Furthermore, the tensile stress relaxation testing system for copper and copper alloy strips and foils also includes: The tensile loading control unit 103 is used to control the tensile loading of the copper and copper alloy strip and foil samples according to the test metadata.

[0063] In this embodiment of the invention, the tensile loading control unit 103 determines the tensile rate and target strain according to the test metadata, and then performs tensile control on the copper and copper alloy strip foil samples according to the tensile rate, and performs real-time tensile monitoring to obtain the real-time tensile amount. At the same time, it calculates the real-time strain based on the real-time tensile amount, and compares the real-time strain with the target strain. When the real-time strain reaches the target strain, it maintains a constant strain.

[0064] The test index calculation unit 104 is used to collect synchronous test data according to a preset sampling frequency, and to perform anomaly removal and index calculation on the synchronous test data to obtain synchronous index data.

[0065] In this embodiment of the invention, the test index calculation unit 104 collects synchronous test data including sampling time, real-time tensile amount, temperature, humidity and clamping force according to a preset sampling frequency, and performs abnormal identification of numerical changes in the synchronous test data. The identified abnormal data is then removed to achieve effective optimization of the synchronous test data and obtain valid test data. Based on the valid test data, index calculation is performed to obtain synchronous index data including initial stress, real-time stress, stable stress and relaxation rate.

[0066] The test report generation unit 105 is used to generate a stress relaxation curve based on the synchronous index data, compare it with the corresponding standard relaxation curve, and generate a relaxation test report.

[0067] In this embodiment of the invention, the test report generation unit 105 generates a stress relaxation curve based on the synchronous index data, and matches a standard relaxation curve based on the test metadata. By comparing the stress relaxation curve with the standard relaxation curve, the degree of fit between the stress relaxation curve and the standard relaxation curve is identified, and it is determined whether the copper and copper alloy strip and foil samples are qualified. The qualified judgment information is obtained, and then the sample characteristic data, synchronous index data, stress relaxation curve and qualified judgment information are filled in and organized according to the preset standard report format to generate a relaxation test report for the copper and copper alloy strip and foil samples.

[0068] In a preferred embodiment provided by the present invention, the test report generation unit 105 specifically includes: The stress curve generation module 1051 is used to generate a stress relaxation curve based on the synchronization index data. The standard defect matching module 1052 is used to match a standard relaxation curve based on the test metadata. The pass / fail judgment module 1053 is used to compare the stress relaxation curve with the standard relaxation curve to determine whether the copper and copper alloy strip and foil sample is qualified and to obtain pass / fail judgment information. The test report generation module 1054 is used to generate a relaxation test report based on the sample characteristic data, the synchronization index data, the stress relaxation curve, and the pass / fail judgment information.

[0069] It should be understood that although the steps in the flowcharts of the various embodiments of the present invention are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the various embodiments may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0070] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0071] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

[0073] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for testing tensile stress relaxation in copper and copper alloy strips and foils, characterized in that, The method specifically includes the following steps: Binocular imaging was performed on copper and copper alloy strip and foil samples to acquire binocular imaging data, which was then identified to obtain sample feature data and matched with corresponding test metadata. Perform testing, calibration, and environmental control to determine whether the testing conditions are met, and pre-treat the copper and copper alloy strip and foil samples when the testing conditions are met. According to the aforementioned test metadata, tensile loading control was applied to the copper and copper alloy strip and foil samples. Synchronous test data is collected according to a preset sampling frequency, and anomaly removal and index calculation are performed on the synchronous test data to obtain synchronous index data. Based on the synchronous index data, a stress relaxation curve is generated and compared with the corresponding standard relaxation curve to generate a relaxation test report.

2. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 1, characterized in that, The process of performing binocular imaging on copper and copper alloy strip and foil samples, acquiring binocular imaging data, identifying sample feature data, and matching corresponding test metadata specifically includes the following steps: Binocular imaging was performed on copper and copper alloy strip and foil samples to obtain binocular imaging data; The length, width, and thickness of the binocular imaging data are identified and recorded to obtain sample feature data; Based on the sample characteristic data, match the corresponding foil sample type; Match the corresponding test metadata based on the type of foil sample.

3. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 1, characterized in that, The process of conducting test calibration and environmental control to determine whether the test conditions are met, and pre-treating the copper and copper alloy strip / foil samples when the test conditions are met, specifically includes the following steps: Perform force sensing zero-point calibration and displacement range calibration, and record the calibration data; The calibration data is compared with historical data to determine whether the deviation exceeds the limit; When the deviation is within the limit, temperature and humidity are controlled according to the test metadata, and it is determined whether the environmental conditions are met. After the environmental conditions are met, a preload force is applied to the copper and copper alloy strip and foil samples.

4. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 1, characterized in that, The tensile loading control of the copper and copper alloy strip / foil samples according to the test metadata specifically includes the following steps: Determine the tensile rate and target strain based on the aforementioned test metadata; The copper and copper alloy strip and foil samples were subjected to tensile control according to the tensile rate, and the real-time tensile amount was determined. Calculate the real-time strain based on the real-time tensile amount; When the real-time strain reaches the target strain, a constant strain is maintained.

5. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 1, characterized in that, The process of collecting synchronous test data according to a preset sampling frequency, and performing anomaly removal and index calculation on the synchronous test data to obtain synchronous index data specifically includes the following steps: According to the preset sampling frequency, synchronous test data is collected, including sampling time, real-time tensile amount, temperature, humidity and clamping force; The synchronous test data is subjected to anomaly identification and removal processing for numerical mutations to obtain valid test data; Based on the valid test data, index calculations are performed to obtain synchronous index data, which includes initial stress, real-time stress, stable stress, and relaxation rate.

6. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 5, characterized in that, The step of calculating the metrics and obtaining the synchronization metric data based on the valid test data specifically includes the following steps: Traverse the valid test data, identify the starting time point when the tensile loading control stage ends and enters the constant strain holding state, extract the clamping force data corresponding to this time point, calculate the initial stress value by combining it with the real-time cross-sectional area in the sample feature data, and record the corresponding sampling time as the initial stress timestamp to obtain the initial stress data containing the initial stress value and the initial stress timestamp. Extract the clamping force data corresponding to all sampling time points after the initial stress timestamp, and perform continuous calculations in combination with the real-time cross-sectional area in the sample feature data to generate a real-time stress data sequence that corresponds one-to-one with each sampling time point, so as to obtain a real-time stress dataset. A stationarity analysis is performed on the real-time stress dataset to identify continuous time periods in which the rate of stress change is consistently lower than a preset stability threshold. The arithmetic mean of all real-time stress data within this time period is extracted as the stable stress value, and the starting time of this time period is recorded as the stability start time. The calculation windows are divided into multiple equal-duration calculation windows between the initial stress timestamp and the stable start time. For the real-time stress data sequence in each calculation window, the ratio of its stress decay to the corresponding duration is calculated to obtain the relaxation rate sequence corresponding to multiple calculation windows. By integrating initial stress data, real-time stress dataset, stable stress values ​​and their stabilization start time, and relaxation rate sequence, and aligning and correlating them according to sampling time, a structured index set containing time-dimensional correspondences is generated to obtain a preliminary synchronization index dataset. The initial synchronization index dataset is subjected to integrity verification and timing consistency verification. Redundant or conflicting entries caused by alignment are removed to obtain the synchronization index data.

7. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 6, characterized in that, The process of identifying and removing numerical mutations in the synchronized test data to obtain valid test data specifically includes the following steps: The synchronous test data is divided into continuous data segments according to a preset time window, and the baseline statistical value of each parameter is calculated independently for each data segment. The baseline statistical value includes the arithmetic mean. The real-time data of each parameter in the synchronous test data is compared with the baseline statistical value of the data segment to which the parameter belongs: if a single point of data deviates from the arithmetic mean by more than a preset dispersion threshold, it is marked as an isolated outlier; if the rate of change of two consecutive points of data exceeds the baseline change trend range, it is marked as a continuous mutation point; if the environmental parameter exceeds the allowable range of the test metadata, it is marked as an environmental failure point, and the anomaly type label set is generated by associating the labeling results; the environmental parameters include temperature and humidity; Physical rules are established based on the stress-strain relationship of copper and copper alloy strips and foils: the rationality of clamping force fluctuations is verified by real-time tensile changes, and the continuity of environmental parameter changes is verified by historical temperature and humidity trends; the abnormality type marker set is substituted into the physical rules for secondary verification: if the clamping force mutation point does not correspond to a reasonable tensile change, the point is confirmed as an equipment interference anomaly; if the environmental parameter mutation point does not show continuous change characteristics, the point is confirmed as a sensor distortion anomaly, so as to obtain the final abnormal point location set. All abnormal data points are removed from the final set of outlier points to generate a data sequence with null values. A differentiated repair strategy is used to fill the null values: isolated null values ​​are filled by linear interpolation of adjacent data, and continuous null value segments are filled by the moving average of adjacent data segments to obtain the repaired data sequence. Identify and repair sections in the data sequence where environmental parameters undergo non-abrupt drift, and dynamically compensate for the real-time stretching and clamping force of these sections to obtain an environmental coupling compensation dataset. The dynamic compensation includes: compensating the clamping force according to a preset ratio when the temperature continues to shift, and correcting the stretching amount according to material properties when the humidity continues to shift. Temporal consistency analysis is performed on the environmental coupling compensation dataset: if the parameter feature quantity undergoes a jump without environmental support between adjacent data segments, it is determined to be a hidden abnormal segment. Dynamic smoothing processing based on feature quantity changes is applied to the data of this segment to obtain the re-verification dataset. The re-validation dataset is reassembled according to the original time sequence, and the original data corresponding to all outliers are removed. The valid data points that have passed the full process validation are retained to obtain valid test data.

8. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 1, characterized in that, The process of generating a stress relaxation curve based on the synchronization index data, comparing it with the corresponding standard relaxation curve, and generating a relaxation test report specifically includes the following steps: Based on the aforementioned synchronization index data, a stress relaxation curve is generated; Based on the test metadata, a standard relaxation curve is matched; The stress relaxation curve is compared with the standard relaxation curve to determine whether the copper and copper alloy strip and foil samples are qualified, and the qualification information is obtained. A relaxation test report is generated based on the sample characteristic data, the synchronization index data, the stress relaxation curve, and the pass / fail judgment information.

9. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 8, characterized in that, The process of generating the stress relaxation curve based on the synchronization index data specifically includes the following steps: Extract real-time stress and corresponding sampling time from the synchronous index data, and divide the data into continuous time periods according to a preset duration; aggregate stress data independently for each time period to generate a segmented aggregated dataset containing the average stress at the beginning of the time period, the stress extreme value within the time period, and the stress attenuation at the end of the time period. Traverse the segmented aggregated dataset to identify stress change characteristics: when the stress attenuation within a time period exceeds a preset change threshold, it is marked as an accelerated relaxation inflection point; when the deviation between the stress value at the end of the time period and the average stress value at the beginning of the next time period is less than a preset tolerance, it is marked as the starting point of the steady state; the segment with the largest span between adjacent accelerated relaxation inflection points is marked as the main relaxation stage to obtain an aggregated dataset with inflection point markings. Based on the aggregated dataset with inflection point labels, a high-precision fitting strategy is used to generate a continuous curve for the main relaxation phase; an initial stress constraint fitting is used for the section before the inflection point of accelerated relaxation; an asymptotic convergence fitting is used for the section after the steady-state starting point; and a smooth transition processing is applied at the inflection point junction to eliminate step abrupt changes in order to obtain the fitted curve segment. Extract the periods of sudden changes in environmental parameters from the synchronous index data, identify the overlapping sections of the fitted curve segments with the periods of sudden changes in environmental parameters; based on the environmental sensitivity parameters of the material in the test metadata, perform reverse compensation on the stress values ​​of the overlapping sections: when the temperature rises, adjust the stress values ​​upward according to a preset ratio, and when the humidity is abnormal, adjust the stress values ​​downward according to the material's moisture absorption characteristics, so as to obtain the environmentally compensated curve. The stress change rate of the curve after environmental compensation is scanned, and oscillation segments where the frequency of alternating positive and negative changes exceeds a preset threshold are identified. A reference envelope is generated based on the stress change trend of adjacent non-oscillation segments. The data of the oscillation segment is constrained to the range of the reference envelope, the trend characteristics are preserved and high-frequency fluctuations are suppressed, so as to obtain a continuous curve after oscillation suppression. After oscillation suppression, the continuous curves are spliced ​​along the time axis, and the marked inflection point information is inserted to generate a stress relaxation curve; the stress relaxation curve fully retains the characteristics of the three stages of accelerated relaxation, main relaxation and steady state.

10. The method for testing tensile stress relaxation of copper and copper alloy strips and foils according to claim 8, characterized in that, The step of comparing the stress relaxation curve with the standard relaxation curve to determine whether the copper and copper alloy strip / foil samples are qualified, and obtaining qualification information, specifically includes the following steps: The feature point set is extracted from the stress relaxation curve and the standard relaxation curve. The feature point set includes the initial stress point, the starting point of the main relaxation stage, the inflection point position, and the stable stress convergence point. The feature point set of the stress relaxation curve and the standard relaxation curve is time-aligned using a dynamic time warping algorithm to obtain the aligned feature point sequence. Based on the aligned feature point sequence, the stress difference between the stress relaxation curve and the standard relaxation curve at each stage is calculated, and the maximum deviation, average deviation and deviation change trend are statistically analyzed to obtain a set of segmented difference indices. Based on the predefined tolerance range in the test metadata, the compliance of the segmented difference index set is determined. If the stress difference value of a certain stage exceeds the upper limit of the tolerance, it is marked as an out-of-tolerance segment, and the duration and magnitude of the out-of-tolerance are recorded to obtain the out-of-tolerance marking result set. By integrating the segmented difference index set and the out-of-tolerance label result set, and introducing the material use scenario weight coefficient, the severity level of the out-of-tolerance segment is assessed. If the out-of-tolerance occurs in the initial stage, a higher weight is assigned, and if it occurs in the stable stage, a lower weight is assigned, so as to obtain the weighted out-of-tolerance assessment result. Based on the weighted out-of-tolerance assessment results, determine whether the sample is qualified: if the weighted assessment results of all out-of-tolerance sections do not exceed the preset tolerance threshold, the sample is deemed qualified; if the weighted assessment result of any out-of-tolerance section exceeds the tolerance threshold, the sample is deemed unqualified, and defect description information including out-of-tolerance location, out-of-tolerance magnitude, and duration is generated; combining the qualification judgment conclusion and the defect description information, a qualification judgment information is generated.

11. A tensile stress relaxation testing system for copper and copper alloy strips and foils, characterized in that, The system applies the tensile stress relaxation test method for copper and copper alloy strips and foils as described in any one of claims 1 to 10. The system includes a binocular imaging and recognition unit, a test calibration and environmental control unit, a tensile loading control unit, a test index calculation unit, and a test report generation unit, wherein: The binocular imaging and recognition unit is used to perform binocular imaging on copper and copper alloy strip and foil samples, acquire binocular imaging data, and perform recognition to obtain sample feature data and match the corresponding test metadata. The test calibration and environment control unit is used to perform test calibration and environmental control, determine whether the test conditions are met, and pre-treat the copper and copper alloy strip foil samples when the test conditions are met. A tensile loading control unit is used to control the tensile loading of the copper and copper alloy strip and foil samples according to the test metadata. The test index calculation unit is used to collect synchronous test data according to a preset sampling frequency, and to perform anomaly removal and index calculation on the synchronous test data to obtain synchronous index data. The test report generation unit is used to generate a stress relaxation curve based on the synchronous index data, compare it with the corresponding standard relaxation curve, and generate a relaxation test report. The binocular imaging and recognition unit specifically includes: A binocular imaging module is used to perform binocular imaging on copper and copper alloy strip and foil samples to acquire binocular imaging data. The identification and recording module is used to identify the length, width, and thickness of the binocular imaging data, record the data, and obtain sample feature data. A foil sample type matching module is used to match the corresponding foil sample type based on the sample feature data; The test metadata matching module is used to match the corresponding test metadata according to the type of the foil sample. Specifically, the test calibration and environment control unit includes: The calibration recording module is used to perform force sensing zero-point calibration and displacement range calibration, and to record the calibration data. The data comparison module is used to compare the calibration data with historical data to determine whether the deviation exceeds the limit; The environmental control module is used to control the temperature and humidity according to the test metadata when the deviation does not exceed the limit, and to determine whether the environmental conditions are met. A preload force application module is used to apply a preload force to the copper and copper alloy strip and foil samples after environmental conditions are met. The test report generation unit specifically includes: The stress curve generation module is used to generate a stress relaxation curve based on the synchronization index data. A standard defect matching module is used to match a standard relaxation curve based on the test metadata. The pass / fail judgment module is used to compare the stress relaxation curve with the standard relaxation curve to determine whether the copper and copper alloy strip and foil samples are qualified and to obtain pass / fail judgment information. The test report generation module is used to generate a relaxation test report based on the sample characteristic data, the synchronization index data, the stress relaxation curve, and the pass / fail judgment information.

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