A tensile hydrogen embrittlement evaluation apparatus and method with local hydrogen input correction

Abstract

The application discloses a local hydrogen input correction tensile hydrogen embrittlement evaluation device, which comprises a local window forming structure for tightly sealing a tensile sample and defining an effective exposure domain on the surface of the tensile sample, which is in communication with a hydrogen charging medium, so that the tensile sample is locally permeated with hydrogen only at the effective exposure domain; an electrochemical hydrogen charging and detection unit for charging hydrogen to the tensile sample and detecting the current on the oxidation side of the tensile sample; a slow strain rate tensile unit for applying an axial tensile load to the tensile sample; a synchronous acquisition unit for synchronously acquiring the current on the oxidation side, a background current, a tensile load, a strain and a fracture time and a fracture position; and a data processing unit connected with the synchronous acquisition unit, so that the difference of the final hydrogen embrittlement evaluation quantity can truly reflect the response of the material to the local hydrogen permeation condition, thereby improving the comparability, reliability and traceability of the local hydrogen embrittlement evaluation result. The application also discloses a local hydrogen input correction tensile hydrogen embrittlement evaluation method.

Description

Technical Field

[0001] This invention belongs to the field of hydrogen embrittlement sensitivity assessment technology, and in particular relates to a tensile hydrogen embrittlement assessment device and method with local hydrogen input correction. Background Technology

[0002] When metallic materials operate in hydrogen-containing environments, hydrogen atoms can penetrate the material's interior through corrosion, cathodic protection, electrochemical hydrogen charging, gaseous hydrogen, or localized defects. They can accumulate near tensile loads, residual stresses, welded joints, notches, or pitting pits. Oil and gas pipelines, hydrogen pipelines, marine engineering structures, high-strength steel fasteners, pressure vessel steel, and welded joints are all susceptible to hydrogen embrittlement. Common testing methods include electrochemical hydrogen permeation testing, tensile testing after hydrogen charging, and in-situ electrochemical hydrogen charging slow strain rate tensile testing. Electrochemical hydrogen permeation testing can obtain information on hydrogen diffusion and permeation current, but it may not simultaneously reflect tensile damage. In-situ electrochemical hydrogen charging slow strain rate tensile testing can simultaneously obtain mechanical curves and hydrogen charging conditions, but common methods focus more on device clamping, corrosive environments, or final mechanical properties.

[0003] One current method for hydrogen embrittlement testing is as follows: A standard or notched tensile specimen is prepared, and its surface is ground, polished, cleaned, and coated as necessary. An electrochemical hydrogen-filled cell or a dual-electrolysis cell is used to define the localized or overall exposure area of ​​the specimen. Hydrogen filling or hydrogen permeation testing is initiated, and tensile testing is performed at a set slow strain rate. Stress-strain curves, electrochemical current curves, and fracture locations are collected. Finally, the changes in reduction of area, elongation, or strength are compared with a hydrogen-free control specimen. This scheme can perform hydrogen permeation detection under in-situ hydrogen-filled tensile or loaded conditions. When comparing different local hydrogen permeation areas and regions, if only the window size or window position is used as a grouping condition and the final loss rate is compared, the area or position will be directly correlated with the result difference. However, the result is also affected by factors such as the amount of hydrogen input corresponding to the effective area, the stress state corresponding to the window position, and whether the sealing and fracture positions meet the preset conditions. Therefore, it cannot be directly attributed to the window area or position itself. In this case, if only the local window area is changed, the larger the window, the greater the total amount of hydrogen input that can enter the material. If flux normalization is not performed according to the effective exposure area and the sample is not restricted to the same target coupled dose window, the final loss rate difference may come from the difference in hydrogen input, rather than from the material's true response to the local area change.

[0004] Existing in-situ hydrogen-filled slow strain rate tensile devices and hydrogen permeation testing devices under loading conditions can combine hydrogen-filled environment, electrochemical detection, and tensile testing. Existing hydrogen embrittlement evaluation methods usually use indicators such as reduction of area loss rate, elongation loss rate, or fracture time. However, they do not address the comparability of different local windows. Before the samples enter the final evaluation, they uniformly record parameters such as effective exposure area, hydrogen input per unit area, window stress participation, load participation period, fracture acceptance zone, invalid reason code, and next test condition version, and put these factors into the same set of records and acceptance rules to confirm whether the samples are comparable before calculating hydrogen embrittlement indicators. It is evident that this can easily lead to biases in the attribution of hydrogen embrittlement causes. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a tensile hydrogen embrittlement assessment device and method with local hydrogen input correction. This ensures that the difference in the final hydrogen embrittlement assessment truly reflects the material's response to local hydrogen permeation conditions, rather than being an artifact caused by window area, stress state, time synchronization, or fracture attribution deviation. This significantly improves the comparability, reliability, and traceability of local hydrogen embrittlement assessment results.

[0006] The present invention provides a tensile hydrogen embrittlement assessment device with local hydrogen input correction, comprising:

[0007] A localized window forming structure is used to compress and seal the tensile specimen, defining an effective exposure area on the surface of the tensile specimen that communicates with the hydrogen-filled medium. So that the tensile specimen is only in the effective exposure area. Localized hydrogen permeation occurred at the site;

[0008] An electrochemical hydrogen charging and detection unit is used to charge the tensile specimen with hydrogen and detect the oxidation side current passing through the tensile specimen.

[0009] A slow strain rate tensile unit is used to apply an axial tensile load to the tensile specimen.

[0010] The synchronous acquisition unit is used to synchronously acquire the oxidation side current, background current, tensile load, strain, fracture time, and fracture location.

[0011] The data processing unit, connected to the synchronous acquisition unit, is configured to: establish a local hydrogen input unit using the sample number and window number as indexes; perform pilot calibration; determine background stability based on the background current; and use the coupling dose of the reference local hydrogen input unit as a reference. A target-coupled dose window is established centered on the target; a background-corrected hydrogen permeation current is obtained based on the oxidation-side current and the background current, and the effective exposure domain is determined based on the background-corrected hydrogen permeation current and the effective exposure domain. Effective exposure area Calculate the area-normalized hydrogen flux According to the effective exposure domain Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; for the area-normalized hydrogen flux The window stress participation factor and the load participation function Integrating the product over the effective test period yields the coupling dose. Based on the fracture trajectory and fracture acceptance zone Calculation of the degree of overlap and the breakage overlap coefficient The effectiveness of the local hydrogen input unit is evaluated based on preset acceptance conditions, including the target coupling dose window, generating an effectiveness flag V. If the acceptance fails, an invalid reason code R is written, and the next test condition version is generated. ; and calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are valid with validity marker V.

[0012] Preferably, in the above-mentioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the target coupling dose window is established according to the window position or window type, and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version together with the window conditions.

[0013] Preferably, in the above-mentioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the data processing unit calculates the window stress participation factor. At that time, first, the effective exposure domain is... The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

[0014] Preferably, in the above-mentioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the preset acceptance conditions include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and the coupling dose. Entering the target coupling dose window and the break coincidence coefficient The fracture acceptance criteria are met; the invalid reason code R at least distinguishes between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; the data processing unit, after summarizing the candidate adjustment items corresponding to the invalid reason code R, generates only one version of the next test conditions. The next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation start point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

[0015] Preferably, in the above-described tensile hydrogen embrittlement assessment device with localized hydrogen input correction, the fracture acceptance zone... The effective exposure domain The boundaries of the pre-defined outward expansion distance, notch influence zone, finite element high-stress zone, digital image correlation high-strain zone, or weld heat-affected zone are determined; the fracture coincidence coefficient is mentioned. Falling into the fracture receiving area according to the fracture trajectory The length of the fracture trajectory is determined by the proportion of the fracture length to the total length of the fracture trajectory, the proportion of the fracture surface projection area, or the location of the fracture center.

[0016] This invention provides a method for assessing tensile hydrogen embrittlement with local hydrogen input correction, utilizing a tensile hydrogen embrittlement assessment device with local hydrogen input correction as described in any of the above claims, comprising:

[0017] S1. Prepare a tensile specimen. A local window is formed on the surface of the tensile specimen through the local window forming structure to define the effective exposure area. And record the window number and window position;

[0018] S2. Determine the effective exposure area. and its effective exposure area ;

[0019] S3. Establish a local hydrogen input unit using the sample number and the window number as indexes;

[0020] S4. Perform pilot calibration, determine background stability based on background current, and use the coupling dose of the reference local hydrogen input unit. Establish a target-coupled dose window centered on the target;

[0021] S5. Conduct in-situ local hydrogen permeation and slow strain rate tensile synchronous test, and synchronously acquire oxidation side current, background current, tensile load, strain, fracture time and fracture location through the synchronous acquisition unit.

[0022] S6. Based on the effective exposure area Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ;

[0023] S7. Obtain the background-corrected hydrogen permeation current based on the oxidation-side current and the background current, and then determine the background-corrected hydrogen permeation current based on the effective exposure area. Calculate the area-normalized hydrogen flux and the area-normalized hydrogen flux The window stress participation factor and the load participation function Integrating the product over the effective test period yields the coupling dose. ;

[0024] S8. Determine the fracture acceptance zone And based on the fracture trajectory and the fracture receiving area Calculation of the degree of overlap and the breakage overlap coefficient ;

[0025] S9. Perform effectiveness acceptance based on preset acceptance conditions, including the target coupling dose window, generate an effectiveness flag V, and write an invalidity reason code R if the acceptance fails and generate the next test condition version. ;

[0026] S10. Calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are marked as valid by validity marker V.

[0027] Preferably, in the above-described tensile hydrogen embrittlement assessment method with local hydrogen input correction, in step S6, the window stress participation factor is calculated. At that time, first, the effective exposure domain is... The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

[0028] Preferably, in the above-mentioned tensile hydrogen embrittlement assessment method with local hydrogen input correction, in step S4, the target coupling dose window is established according to the window position or window type, and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version together with the window conditions.

[0029] Preferably, in the above-mentioned tensile hydrogen embrittlement assessment method with local hydrogen input correction, in step S9, the preset acceptance conditions include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and the coupling dose. Entering the target coupling dose window and the break coincidence coefficient The fracture acceptance criteria are met; the invalid reason code R at least distinguishes between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; after summarizing the candidate adjustment items corresponding to the invalid reason code R, only one version of the next test condition is generated. The next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation start point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

[0030] Preferably, in the above-described tensile hydrogen embrittlement assessment method with local hydrogen input correction, in step S10, the hydrogen embrittlement evaluation quantity includes the hydrogen embrittlement loss rate. The hydrogen embrittlement loss rate The relative loss rate of reduction of area, elongation after fracture, or fracture displacement between the hydrogen-free control sample and the partially hydrogen-permeated sample; the hydrogen embrittlement evaluation metric also includes the sensitivity to unit coupled dose. This is used to compare the plasticity loss corresponding to a unit coupling permeation dose.

[0031] As described above, the tensile hydrogen embrittlement assessment device with local hydrogen input correction provided by the present invention includes a local window forming structure for pressing and sealing the tensile specimen, thereby defining an effective exposure area on the surface of the tensile specimen that communicates with the hydrogen-filled medium. So that the tensile specimen is only in the effective exposure area. Localized hydrogen permeation occurs at the location; an electrochemical hydrogen charging and detection unit is used to charge the tensile specimen with hydrogen and detect the oxidation-side current passing through the tensile specimen; a slow strain rate tensile unit is used to apply an axial tensile load to the tensile specimen; a synchronous acquisition unit is used to synchronously acquire the oxidation-side current, background current, tensile load, strain, fracture time, and fracture location; a data processing unit, connected to the synchronous acquisition unit, is configured to: establish a localized hydrogen input unit using the specimen number and window number as indexes; perform pilot calibration, determine background stability based on the background current, and use the coupling dose of the reference localized hydrogen input unit. A target-coupled dose window is established centered on the target; a background-corrected hydrogen permeation current is obtained based on the oxidation-side current and the background current, and the effective exposure domain is determined based on the background-corrected hydrogen permeation current and the effective exposure domain. Effective exposure area Calculate the area-normalized hydrogen flux According to the effective exposure domain Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; for the area-normalized hydrogen flux The window stress participation factor and the load participation function Integrating the product over the effective test period yields the coupling dose. Based on the fracture trajectory and fracture acceptance zone Calculation of the degree of overlap and the breakage overlap coefficient The effectiveness of the local hydrogen input unit is evaluated based on preset acceptance conditions, including the target coupling dose window, generating an effectiveness flag V. If the acceptance fails, an invalid reason code R is written, and the next test condition version is generated. Furthermore, the method calculates the hydrogen embrittlement assessment value for valid local hydrogen input units marked V, thus ensuring that the difference in the final hydrogen embrittlement assessment value truly reflects the material's response to local hydrogen permeation conditions, rather than being an artifact caused by window area, stress state, time synchronization, or fracture attribution deviation. This significantly improves the comparability, reliability, and traceability of local hydrogen embrittlement assessment results. The method provided by this invention has the same advantages. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 A schematic diagram of an embodiment of a tensile hydrogen embrittlement assessment device with local hydrogen input correction provided by the present invention;

[0034] Figure 2 This is a schematic diagram of an embodiment of a tensile hydrogen embrittlement assessment method with local hydrogen input correction provided by the present invention. Detailed Implementation

[0035] The core of this invention is to provide a tensile hydrogen embrittlement assessment device and method with local hydrogen input correction, which can ensure that the difference in the final hydrogen embrittlement evaluation quantity truly reflects the material's response to local hydrogen permeation conditions, rather than an illusion caused by window area, stress state, time synchronization, or fracture attribution deviation. This can significantly improve the comparability, reliability, and traceability of local hydrogen embrittlement assessment results.

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] An example implementation of the tensile hydrogen embrittlement assessment device with local hydrogen input correction provided by the present invention is as follows: Figure 1 As shown, Figure 1 This is a schematic diagram of an embodiment of a tensile hydrogen embrittlement assessment device with local hydrogen input correction provided by the present invention. The device may include:

[0038] Local window forming structure 1 is used to compress and seal the tensile specimen, defining an effective exposure area on the surface of the tensile specimen that is in communication with the hydrogen-filled medium. This ensures that the tensile specimen is only exposed within the effective exposure area. Localized hydrogen permeation occurred at the site;

[0039] Specifically, the local window formation structure can be composed of a dual electrolytic cell housing, sealing gaskets, and clamping components. The sealing gaskets include polytetrafluoroethylene (PTFE) gaskets and silicone gaskets, which are connected by nano-adhesive and clamped by the dual electrolytic cell housing and clamping components. This ensures that only the sample area corresponding to the inner hole of the gasket is in contact with the electrolyte, while the remaining areas are isolated from the electrolyte. The sample surface area corresponding to the inner hole of the gasket is the effective exposure area. For each window, record its shape, center coordinates, distance from the notch tip or weld boundary, sample thickness, and window number. In other embodiments, a corrosion-resistant shielding film, a micro-electrolysis cell, a replaceable clamping fixture, or a localized vapor-phase hydrogen-filled cavity can be used to form an effective exposure area. As long as the effective exposure area can be recorded Only background inspection and area inspection need to be completed; there are no restrictions here.

[0040] Electrochemical hydrogen charging and detection unit 2 is used to charge the tensile sample with hydrogen and detect the current through the oxidation side of the tensile sample.

[0041] Specifically, the electrochemical hydrogen charging and detection unit can employ a Devanathan-Stachurski dual electrolytic cell. On the hydrogen charging side, the platinum electrode is connected to the positive terminal of the hydrogen charging power supply, and the tensile sample is connected to the negative terminal. On the oxidation side, the tensile sample serves as the working electrode and is connected to the electrochemical workstation along with a saturated calomel reference electrode and a platinum auxiliary electrode. For example, the electrolyte on the hydrogen charging side can be... of With 3g / L Mixed solutions, oxidation-side detection solutions can be used of The solution, the hydrogen charging current density can be In other embodiments, hydrogen input methods can also include constant current hydrogen charging, constant potential hydrogen charging, high-pressure gas phase hydrogen charging, or environmental corrosion hydrogen charging. When the oxidation-side current cannot be directly obtained, an area-normalized hydrogen flux can be established using equivalent hydrogen charging parameters that can be converted into hydrogen input. Or area-normalized cumulative hydrogen input No restrictions are imposed here.

[0042] Slow strain rate tensile element 3 is used to apply axial tensile load to the tensile specimen.

[0043] Specifically, the slow strain rate tensile unit uses upper and lower clamps to hold the two ends of the tensile specimen, applying axial tension to the specimen at a low strain rate. This couples hydrogen diffusion, localized stress, and plastic deformation on the same timescale; for example, the strain rate can be... Or the stretching speed can be Those skilled in the art can make reasonable selections based on the material grade, sample thickness, and evaluation purpose; no restrictions are imposed here.

[0044] Synchronous acquisition unit 4 is used to synchronously acquire oxidation side current, background current, tensile load, strain, fracture time and fracture location.

[0045] Specifically, the time recording of the slow strain rate stretching unit and the electrochemical workstation are aligned with a common start-up time, and the synchronous acquisition unit synchronously acquires the oxidation-side current. Background current Tensile load ,strain The hydrogen charging start time, tensile start time, fracture time, and fracture location are used as the function for subsequent load participation. It provides a unified time benchmark for the verification of the effectiveness of calculation and time synchronization.

[0046] Data processing unit 5, connected to the synchronous acquisition unit, is configured to: establish a local hydrogen input unit using the sample number and window number as indexes; perform pilot calibration; determine background stability based on the background current; and use the coupling dose of the reference local hydrogen input unit. A target-coupled dose window is established centered on the target; a background-corrected hydrogen permeation current is obtained based on the oxidation-side current and the background current, and the effective exposure domain is determined based on the background-corrected hydrogen permeation current. Effective exposure area Calculate the area-normalized hydrogen flux According to the effective exposure domain Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; for area-normalized hydrogen flux Window stress participation factor and load participation function Integrating the product over the effective test period yields the coupling dose. Based on the fracture trajectory and fracture acceptance zone Calculation of the degree of overlap and the breakage overlap coefficient The effectiveness of the local hydrogen input unit is verified based on preset acceptance conditions, including the target coupling dose window, and an effectiveness flag V is generated. If the acceptance fails, an invalid reason code R is written and the next test condition version is generated. ; and calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are valid with validity marker V.

[0047] Specifically, the data processing unit can be a local hydrogen input unit running on a computer, performing functions such as table recording, pilot calibration, coupled dose calculation, load synchronization acceptance, fracture acceptance, invalid reason code recording, and test condition version recording. These functions can be implemented by a table or data processing program on the same computer, rather than by separate physical devices. The local hydrogen input unit must at least record the sample number, window number, and effective exposure area. Effective exposure area Background current, leader calibration parameters, window stress participation factor, load participation function, target coupled dose window, fracture receiving zone Fracture coincidence coefficient Validity marker V, invalidity reason code R, and next test condition version It serves as a common index for electrochemical data, tensile data, fracture location, and evaluation output; the condition version recording function will correspond invalid reason code R to the next physical test action such as replacing the seal, replacing the window, adjusting the common start-up time, adjusting the hydrogen charging current or hydrogen charging time.

[0048] As described above, in the embodiments of the tensile hydrogen embrittlement assessment device with local hydrogen input correction provided by the present invention, a local window forming structure is included to compress and seal the tensile specimen, thereby defining an effective exposure area on the surface of the tensile specimen that communicates with the hydrogen-filled medium. This ensures that the tensile specimen is only exposed within the effective exposure area. Localized hydrogen permeation occurs at the location; an electrochemical hydrogen charging and detection unit is used to charge the tensile specimen with hydrogen and detect the oxidation-side current passing through the tensile specimen; a slow strain rate tensile unit is used to apply axial tensile load to the tensile specimen; a synchronous acquisition unit is used to synchronously acquire oxidation-side current, background current, tensile load, strain, fracture time, and fracture location; a data processing unit, connected to the synchronous acquisition unit, is configured to: establish a localized hydrogen input unit using the specimen number and window number as indexes; perform pilot calibration, determine background stability based on the background current, and use the coupling dose of the reference localized hydrogen input unit. A target-coupled dose window is established centered on the target; the background-corrected hydrogen permeation current is obtained based on the oxidation-side current and the background current, and the effective exposure domain is determined based on the background-corrected hydrogen permeation current. Effective exposure area Calculate the area-normalized hydrogen flux According to the effective exposure domain Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; for area-normalized hydrogen flux Window stress participation factor and load participation function Integrating the product over the effective test period yields the coupling dose. Based on the fracture trajectory and fracture acceptance zone Calculation of the degree of overlap and the breakage overlap coefficient The effectiveness of the local hydrogen input unit is verified based on preset acceptance conditions, including the target coupling dose window, and an effectiveness flag V is generated. If the acceptance fails, an invalid reason code R is written and the next test condition version is generated. Furthermore, the hydrogen embrittlement evaluation quantity is calculated for effective local hydrogen input units marked V. Therefore, it can ensure that the difference in the final hydrogen embrittlement evaluation quantity truly reflects the material's response to local hydrogen permeation conditions, rather than the artifacts caused by window area, stress state, time synchronization, or fracture attribution deviation. This can significantly improve the comparability, reliability, and traceability of local hydrogen embrittlement assessment results.

[0049] In a specific embodiment of the above-mentioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the target coupling dose window is established according to the window position or window type and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version along with the window conditions.

[0050] Specifically, pilot calibration can continuously record for at least 3600 seconds on the same batch of reference local hydrogen input cells or the same window before the formal test; when the oxidation-side background current is lower than If the coefficient of variation of the background current is no greater than 5% within the last 600 seconds, the background is considered stable; the effective coupling dose of the reference local hydrogen input unit at the same window position is used. Establish a target coupling dose window of ±10% around the center. Separate windows are created for the center window and the non-center window, without requiring them to have the same coupling dose. The hydrogen charging current density, oxidation potential, calibration duration, load co-triggering time, window stress participation factor value table, and window conditions are all included in the test condition version. 3600s is the value used in this embodiment. When the material thickness or surface condition changes, the calibration time can be extended, but the target coupling dose window must not be changed in reverse after the test.

[0051] In another specific embodiment of the aforementioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the data processing unit calculates the window stress participation factor. At that time, first target the effective exposure domain. The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

[0052] Specifically, the area-average equivalent stress is calculated according to... Calculation, where To effectively expose the domain The equivalent stress field within the same batch is then compared with the maximum value within the same effective loading interval within the same batch comparison window. As ,make ; Window segments with the same geometry and loading conditions in uniform parallel segments can be uniformly selected. The notched specimens were averaged and normalized according to the finite element stress field. The stress concentration factor Kt was only used to determine the specimen geometry and was not directly used to replace the stress concentration factor Kt. For example, take When the notch center window has the following window stress participation factors at nodes 0.3Rel, 0.6Rel, 0.9Rel, and Rm: The values ​​are 0.32, 0.61, 0.82, and 1.00 respectively, and the values ​​for non-center windows are 0.24, 0.43, 0.58, and 0.68 respectively. Linear interpolation is used between adjacent nodes. For yield strength, For tensile strength; in other embodiments, area-average equivalent stress. It can also be derived from digital image correlation strain calculation, strain gauge measurement, or load-to-cross-sectional area conversion, load participation function. The values ​​can also be taken in segments according to the pre-locked stress or strain nodes, but they must not be changed after the test to accommodate the results; there is no restriction here.

[0053] In another specific embodiment of the aforementioned tensile hydrogen embrittlement assessment device with local hydrogen input correction, the preset acceptance conditions include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and coupling dose. Entering the target coupling dose window and the breakover coefficient The fracture acceptance criteria are met; the invalid reason code R must at least distinguish between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; the data processing unit will generate only one version of the next test conditions after summarizing the candidate adjustment items corresponding to the invalid reason code R. Next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation start point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

[0054] Specifically, the preset acceptance criteria can be: background current less than Furthermore, the coefficient of variation within the last 600 seconds should not exceed 5%, corresponding to background non-compliance reason code B01; effective exposure area before and after the test. The relative deviation is no greater than 5%, corresponding to area non-compliance reason code A01; the time stamp deviation of current, load, strain and fracture event is no greater than 1s, corresponding to load synchronization non-compliance reason code T01; coupling dose Entering the target coupling dose window within ±10% of the reference value at the same window position corresponds to the coupling dose non-compliance reason code D01; breakage coincidence coefficient A value not less than 0.70 corresponds to the breakage acceptance failure reason code F01. For example, the background current obtained in a certain test... Background coefficient of variation 7.2%, area bias 6.4%, synchronization bias 1.6s, coupling dose Fracture coincidence coefficient Then the validity marker V is for verification, and the invalidity reason code is... At this point, only one version of the next test condition will be generated. Re-nickel plating and inspect the gaskets to treat B01 and A01; calibrate the common trigger clock of the electrochemical workstation and the stretching machine to treat T01; maintain hydrogen charging current density. In this case, the effective hydrogen charging time will be increased by 20%, thus reducing the coupling dose. Increased to approximately It then enters the target coupling dose window to process D01, repositions the window, and breaks the receiving area. To handle F01; proceed to the next test condition version. After retesting, background current The coefficient of variation in the last 600 seconds was 2.6%, the area bias was 2.3%, the synchronization bias was 0.6 seconds, and the coupling dose was [not specified]. Fracture coincidence coefficient All pre-set acceptance conditions were met, therefore the validity marker V of the retest unit was valid, and the invalidation reason code R was marked as PASS, and the next test condition version was not triggered. The process demonstrates the invalid reason code R, the next test condition version, and so on. A complete closed loop of retesting and validity marker V.

[0055] In a preferred embodiment of the aforementioned tensile hydrogen embrittlement assessment device with localized hydrogen input correction, the fracture acceptance zone... From effective exposure domain Determination of the following parameters: pre-defined expansion distance, notch influence zone, finite element high-stress zone, digital image correlation high-strain zone, or weld heat-affected zone boundary; fracture coincidence coefficient. Falling into the fracture acceptance zone according to the fracture trajectory The length of the fracture trajectory is determined by the proportion of the fracture length to the total length of the fracture trajectory, the proportion of the fracture surface projection area, or the location of the fracture center.

[0056] Specifically, the fracture coincidence coefficient ,in The fracture trajectory of the specimen is shown, where L represents the length of the trajectory after dimensional calibration. This can be achieved by taking a vertical photograph with a standard digital camera and placing the scale within the same frame as the specimen, then extracting the fracture trajectory from the image. centerline and fracture acceptance zone Calculate the fracture coincidence coefficient after the boundary. No special measuring equipment is required; when the fracture coincidence coefficient A value below 0.70 only indicates that the fracture cannot be reliably attributed to that window, not that the fracture is not hydrogen embrittlement, and thus becomes a candidate for re-identifying or re-testing the window. For example, the notch center window... , Fracture coincidence coefficient Approximately 0.86; Off-center window , Fracture coincidence coefficient The value is approximately 0.78, and both meet the fracture acceptance condition of 0.70.

[0057] An implementation example of the tensile hydrogen embrittlement assessment method with local hydrogen input correction provided by this invention is as follows: Figure 2 As shown, Figure 2This is a schematic diagram of an embodiment of a tensile hydrogen embrittlement assessment method with local hydrogen input correction provided by the present invention. Using the tensile hydrogen embrittlement assessment apparatus with local hydrogen input correction as described in any of the above claims, the method may include the following steps:

[0058] S1. Prepare a tensile specimen by creating a local window structure on the surface of the tensile specimen to define the effective exposure area. And record the window number and window position;

[0059] Specifically, the tensile specimen can be a standard plate tensile specimen, a notched plate tensile specimen, a welded joint specimen, or a specimen containing a pitting simulated area. Before the test, the specimen surface is sequentially ground, polished, and cleaned, and coated as needed, for example... Nickel plating was performed at a current density of 200s; for each window, the window shape, window center coordinates, distance from the notch tip or weld boundary, sample thickness, and window number were recorded.

[0060] S2. Determine the effective exposure area and its effective exposure area ;

[0061] Specifically, the effective exposure domain The effective exposed area is the sample surface region that is actually connected to the hydrogen-filling medium or the detection medium within the local window. To effectively expose the domain The area, in units of Its calculation formula can be ,in, This refers to the area on the sample surface that is actually connected to the hydrogen-filling medium or the detection medium. The area element can be derived from the window's geometric dimensions, the washer's inner diameter, or pre- and post-trial image calibrations. If the window is a regular circle, it can be determined from the inner diameter... For conversion, if the window is irregularly shaped, it can be converted from the pixel area of ​​the image mask. When using image calibration, the ruler and the window are photographed or scanned together. After completing the size calibration and edge extraction, the conversion is done by pixel area, rather than placing the device on the window and taking the reading directly. When the inner diameters of the hydrogen charging side and the oxidation side windows are the same, this common area is used as the effective exposed area. If the areas on both sides are different, they should be recorded separately and should not be mixed. After the test, the window boundary should be obtained again to determine whether the sealing boundary has drifted.

[0062] S3. Establish local hydrogen input units using sample number and window number as indexes;

[0063] Specifically, the local hydrogen input unit must at least write into the effective exposure domain. Effective exposure area Background current, leader calibration parameters, target coupled dose window, source of window stress participation coefficient, source of load participation function, fracture receiving zone Synchronously collect timestamps, validity markers (V), invalid reason codes (R), and next test condition versions. This unit serves as a common index for electrochemical data, tensile data, fracture locations, and evaluation outputs; the experimental condition version is loaded when establishing this unit for the first experiment. At this point, the next test condition version Empty; only load the version of the next test conditions generated in the previous round during retesting. This is the version of the test conditions for this round.

[0064] S4. Perform pilot calibration, determine background stability based on background current, and use the coupling dose of the reference local hydrogen input unit. Establish a target-coupled dose window centered on the target;

[0065] Specifically, for the same batch of reference local hydrogen input cells or the same window, continuous recording should be performed for at least 3600 seconds before the formal test; when the oxidation-side background current is lower than If the coefficient of variation of the background current is no greater than 5% within the last 600 seconds, the background is considered stable; the effective coupling dose of the reference local hydrogen input unit at the same window position is used. Establish a target coupling dose window of ±10% around the center. Separate windows are created for the center window and the non-center window, without requiring them to have the same coupling dose. The hydrogen charging current density, oxidation potential, calibration duration, load co-triggering time, window stress participation factor value table, and window conditions are all included in the test condition version. 3600s is the value used in this embodiment. When the material thickness or surface condition changes, the calibration time can be extended, but the target coupling dose window must not be changed in reverse after the test.

[0066] S5. Conduct in-situ local hydrogen permeation and slow strain rate tensile synchronous test, and synchronously collect oxidation side current, background current, tensile load, strain, fracture time and fracture location through synchronous acquisition unit.

[0067] Specifically, simultaneous tests were conducted on the hydrogen charging side, the electrochemical detection side, and the tensile testing machine; background correction was applied to the hydrogen permeation current. When the workstation outputs the total current on the oxidation side At that time, by Subtracting pre-passivation or no-load background current The result is given in amperes (A); when the workstation directly outputs current density... When, the background current density of the same unit is deducted. The division by the effective exposure area will not be repeated subsequently. Area-normalized hydrogen flux in total current recording mode In the current density recording method Converted to Then divide directly by the Faraday constant F, and do not divide again by the effective exposed area. ,in , The unit is The local hydrogen input unit simultaneously records the current branch and unit conversion used.

[0068] S6. Based on the effective exposure area Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ;

[0069] Specifically, first calculate the effective exposure domain. Area-average equivalent stress ,in To effectively expose the domain The equivalent stress field within the same batch is then compared with the maximum value within the same effective loading interval within the same batch comparison window. As reference stress ,make Therefore ; Window segments with the same geometry and loading conditions in uniform parallel segments can be uniformly selected. The notched specimens were averaged and normalized according to the finite element stress field, and the stress concentration factor was... Used only to determine the specimen geometry, not directly substituted. Let the common triggering time of electrochemical detection and tensile loading be . The fracture time is Then when hour, ,in This represents the peak load of this test, and the time from reaching the peak load to fracture. Keep it at 1, when , Or time synchronization failure For example in , , and stage, The values ​​are 0.3, 0.6, 0.9, and 1, respectively.

[0070] S7. Obtain the background-corrected hydrogen permeation current based on the oxidation-side current and the background current, and then use the background-corrected hydrogen permeation current and the effective exposure area as a basis. Calculate the area-normalized hydrogen flux and area-normalized hydrogen flux Window stress participation factor and load participation function Integrating the product over the effective test period yields the coupling dose. ;

[0071] Specifically, area-normalized cumulative hydrogen input Area-normalized hydrogen flux Integral over the effective test period: Coupled dose Area-normalized hydrogen flux Window stress participation factor and load participation function The integral of the product over the effective test period: The unit is ,in The common starting point for effective penetration and stretching, The last valid sampling time before the fracture was calculated using the trapezoidal integral of adjacent points from the discrete sampling data. and Coupled dose It is a comparative measure relating local permeation flux, local stress state, and loading stage under the same aperture; it is not considered a material intrinsic constant, nor is it equivalent to the total amount of hydrogen retained inside the sample. The target coupling dose window is set to the reference coupling dose at the same position according to the window location. ±10%; when the load participates in the function No effective overlap or coupling dose If the target coupling dose window is exceeded or the timestamp deviation exceeds 1 second, the corresponding reason code is written and candidate options for adjusting the co-triggering, hydrogen charging duration, or hydrogen charging current are generated. This step does not generate a formal version of the next test conditions. .

[0072] S8. Determine the fracture acceptance zone And based on the fracture trajectory and fracture receiving area Calculation of the degree of overlap and the breakage overlap coefficient ;

[0073] Specifically, the fracture-receiving area From effective exposure domain Determination of the corresponding stress influence zone; fracture coincidence coefficient. ,in The fracture trajectory of the specimen is shown, where L represents the trajectory length after dimensional calibration. Indicates the fracture trajectory With the fracture receiving area The spatial intersection; a regular digital camera can be used to take a vertical picture with the scale and the sample in the same frame, and the fracture trajectory can be extracted from the image. centerline and fracture acceptance zone Calculate the fracture coincidence coefficient after the boundary. No special measuring equipment is required; the fracture coincidence coefficient is predetermined in this embodiment. A value of 0.70 or higher is acceptable. A value below 0.70 only indicates that the fracture cannot be reliably attributed to this window, and does not equate to the fracture not being hydrogen embrittlement. This becomes a candidate for redoing the window location or retesting.

[0074] S9. Perform effectiveness acceptance based on preset acceptance conditions, including the target coupling dose window, generate an effectiveness flag V, and write an invalidity reason code R when the acceptance fails, and generate the next test condition version. ;

[0075] Specifically, the preset acceptance criteria can be: background current less than 1μA and coefficient of variation not greater than 5% in the last 600s; effective exposure area before and after the test. The relative deviation is no greater than 5%; the timestamp deviation of current, load, strain, and fracture event is no greater than 1 second; coupling dose Entering the target coupling dose window within ±10% of the reference value at the same window position; breakover coefficient Not less than 0.70; each item corresponds sequentially to background non-compliance reason code B01, area non-compliance reason code A01, load synchronization non-compliance reason code T01, coupling dose non-compliance reason code D01, and fracture acceptance non-compliance reason code F01; if any item is not met, the validity mark V is re-verified and written into the corresponding invalid reason code R. After summarizing the candidate adjustment items, only one formal version of the next test condition is generated. Next test condition version The adjustment must include at least one of the following: window processing, sealing or surface treatment, synchronous acquisition triggering, load participation start point, hydrogen charging current, hydrogen charging duration, and fracture acceptance zone setting. This adjustment must be locked before retesting and cannot be modified after the retest results are generated. If all conditions are met, the validity flag V is valid; if invalid, the reason code R is recorded as PASS, and the next test condition version will not be triggered. .

[0076] S10. Calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are marked as valid by validity marker V.

[0077] Specifically, hydrogen embrittlement loss rate ,in and The reduction of area (R&A) of the sample is shown for the hydrogen-free control and the sample with partial hydrogen permeation, respectively. Alternatively, the elongation after fracture or the fracture displacement δ can be used instead of the R&A. When using the fracture displacement... Hydrogen embrittlement loss rate All calculations should be performed using dimensionless decimals; for example, 30.60% corresponds to... When displaying percentages externally, use Avoid mixing percentages and decimals; unit-coupled dose sensitivity. When the coupling dose The unit is hour, The unit is , This is used to compare the plastic loss corresponding to a unit coupling permeation dose; it is not an intrinsic material constant and does not replace the hydrogen embrittlement loss rate. In this embodiment, the hydrogen embrittlement loss rate is used. As the primary metric for evaluating hydrogen embrittlement As an auxiliary comparison metric; in other embodiments, hydrogen embrittlement loss rate Alternatively, fracture time reduction rate or local fracture morphology grade can be used, but alternative indicators should be correlated with coupling dose. Fracture coincidence coefficient After being associated with the validity marker V, it enters the evaluation stage.

[0078] In a specific embodiment of the above-described tensile hydrogen embrittlement assessment method with local hydrogen input correction, in step S6, the window stress participation factor is calculated. At that time, first target the effective exposure domain. The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

[0079] For example, for a U-notch plate specimen of X65 pipeline steel with Kt=2.0, take... The average equivalent stress in the region of the gap center window at nodes 0.3Rel, 0.6Rel, 0.9Rel, and Rm is calculated. Take 256MPa, 488MPa, 656MPa, and 800MPa in sequence, and divide by... Back window stress participation factor The values ​​are 0.32, 0.61, 0.82, and 1.00 respectively; for non-centered windows... The corresponding values ​​are 192 MPa, 344 MPa, 464 MPa, and 544 MPa. The values ​​are 0.24, 0.43, 0.58, and 0.68, respectively, with linear interpolation between adjacent nodes; where Rel is the yield strength and Rm is the tensile strength; existing finite element contour plots and transverse stress curves show that the transverse stress differences of the Kt=2.0 specimen at the 0.3Rel, 0.6Rel, 0.9Rel, and Rm stages are 225MPa, 370MPa, 215MPa, and 90MPa, respectively; the above and The calculated values ​​were selected based on the stress distribution trend of the finite element method, and were replaced by the same regional averaging method in actual use.

[0080] In another specific embodiment of the above-mentioned tensile hydrogen embrittlement assessment method with local hydrogen input correction, in S4, the target coupling dose window is established according to the window position or window type, and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version along with the window conditions.

[0081] For example, taking a smooth plate-shaped specimen of X65 pipeline steel with a wall thickness of 14.3 mm as the object, the total length of the specimen is 198 mm, the parallel section is 60 mm, the width is 14 mm, and the window area is A. e =0.5024cm², strain rate is The window is located in a uniform parallel segment, therefore ; Based on the characteristic points of the curve, select t=0, 7000s, 14000s, 21000s, 28000s, and 30000s, and adjust the background current density. The following values ​​were taken sequentially: 0, 9.5, 8.6, 8.0, 10.8, and 11.5 μA. The corresponding load participation functions λ are 0, 0.52, 0.98, 1, 1, and 1, respectively. The results are obtained by trapezoidal integration and taking the Faraday constant. To obtain the reference coupling dose Establish with this value as the center The target coupling dose window; the background current of the reference cell is Area deviation 2.0%, synchronization deviation 0.5s, breakage coincidence coefficient =0.85, all of which meet the preset acceptance conditions, so the validity mark V is valid, and the invalid reason code R is recorded as PASS.

[0082] In another specific embodiment of the above-mentioned tensile hydrogen embrittlement assessment method with local hydrogen input correction, in S9, the preset acceptance conditions include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and coupling dose. Entering the target coupling dose window and the breakover coefficient The fracture acceptance criteria must be met; the invalid reason code R must at least distinguish between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; after summarizing the candidate adjustment items corresponding to the invalid reason code R, only one version of the next test condition will be generated. Next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation start point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

[0083] For example, for a U-notched plate-shaped specimen of X65 pipeline steel with Kt=2.0, the notch radius is 2.45mm, the window radius is 4mm, and the window area is... The stretching speed was 0.012 mm / min. Windows were set at the center of the notch and in the smooth sections outside the center, and a control without hydrogen permeation was set. The coupling dose of the reference cell at the center of the notch was... Corresponding to the target coupled dose window Coupling dose of non-central window reference cell Corresponding to the target coupled dose window The central and non-central windows were constructed using reference units at the same location, and the target coupling dose window was not reversed using the sample to be evaluated after the test. The background currents of the two reference units were 0.43 μA and 0.47 μA, respectively, the area deviations were 2.4% and 2.1%, respectively, and the synchronization deviations were 0.6 s and 0.7 s, respectively, all of which met the preset acceptance conditions. According to the original curve reading, the peak loads of the samples without hydrogen permeation, with hydrogen permeation at the notch center, and without hydrogen permeation at the non-central location were approximately 12.0 kN, 13.2 kN, and 11.8 kN, respectively.

[0084] In a preferred embodiment of the above-described tensile hydrogen embrittlement assessment method with local hydrogen input correction, in S10, the hydrogen embrittlement assessment metric includes the hydrogen embrittlement loss rate. Hydrogen embrittlement loss rate The relative loss rate of reduction of area, elongation after fracture, or fracture displacement between the hydrogen-free control sample and the partially hydrogen-permeated sample; the hydrogen embrittlement evaluation also includes the sensitivity to unit coupled dose. This is used to compare the plasticity loss corresponding to a unit coupling permeation dose.

[0085] For example, based on the fracture displacements of 2.81 mm, 1.95 mm, and 2.64 mm for un-hydrogenated, notch-center-hydrogenated, and non-notch-hydrogenated samples, respectively, the hydrogen embrittlement loss rate at the notch-center window and the non-notch-center window is calculated. The values ​​were 0.3060 (30.60%) and 0.0605 (6.05%), respectively, representing unit coupled dose sensitivity. They are respectively and The center window of the gap It is approximately 15.0 times that of the non-central window; the fracture surface at the center of the notch is dominated by cleavage planes and secondary cracks, while the non-central fracture surface exhibits a mixed morphology of dimples and quasi-cleavage, consistent with the aforementioned loss differences; it should be noted that the coupling dose The hydrogen flux transmitted from the oxidation side is calculated based on window stress and load involvement, and is used to define the comparison aperture between samples. This is not equivalent to the local hydrogen retention capacity of the sample; therefore, the coupling dose of the central window... Lower hydrogen embrittlement loss rate A higher value does not constitute a calculation contradiction. For example, consider the contraction rate without hydrogen. Hydrogen-filled section shrinkage rate The hydrogen embrittlement loss rate was obtained. (i.e., 10.32%), unit coupled dose sensitivity Existing experimental data records that the parent material in and At strain rates, current densities are respectively determined by peak values. , Down to , The decreases were 89.92% and 25.94% respectively; the weld seam was and At strain rates, current densities are respectively from , Down to , The decreases were 73.06% and 24.02%, respectively.

[0086] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A tensile hydrogen embrittlement assessment device with local hydrogen input correction, characterized in that, include: A localized window forming structure is used to compress and seal the tensile specimen, defining an effective exposure area on the surface of the tensile specimen that communicates with the hydrogen-filled medium. So that the tensile specimen is only in the effective exposure area. Localized hydrogen permeation occurred at the site; An electrochemical hydrogen charging and detection unit is used to charge the tensile specimen with hydrogen and detect the oxidation side current passing through the tensile specimen. A slow strain rate tensile unit is used to apply an axial tensile load to the tensile specimen. The synchronous acquisition unit is used to synchronously acquire the oxidation side current, background current, tensile load, strain, fracture time, and fracture location. The data processing unit, connected to the synchronous acquisition unit, is configured to: establish a local hydrogen input unit using the sample number and window number as indexes; perform pilot calibration; determine background stability based on the background current; and use the coupling dose of the reference local hydrogen input unit as a reference. Establish a target-coupled dose window centered on the target; The background-corrected hydrogen permeation current is obtained based on the oxidation-side current and the background current, and the effective exposure domain is then used as the basis for determining the background-corrected hydrogen permeation current. Effective exposure area Calculate the area-normalized hydrogen flux ; According to the effective exposure domain Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; for the area-normalized hydrogen flux The window stress participation factor and the load participation function Integrating the product over the effective test period yields the coupling dose. ; Based on the fracture trajectory and fracture acceptance zone Calculation of the degree of overlap and the breakage overlap coefficient The effectiveness of the local hydrogen input unit is evaluated based on preset acceptance conditions, including the target coupling dose window, generating an effectiveness flag V. If the acceptance fails, an invalid reason code R is written, and the next test condition version is generated. ; and calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are valid with validity marker V.

2. The tensile hydrogen embrittlement assessment device with local hydrogen input correction according to claim 1, characterized in that, The target coupling dose window is established according to the window position or window type and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version along with the window conditions.

3. The tensile hydrogen embrittlement assessment device with local hydrogen input correction according to claim 1, characterized in that, The data processing unit calculates the window stress participation coefficient. At that time, first target the effective exposure domain. The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

4. The tensile hydrogen embrittlement assessment device with local hydrogen input correction according to any one of claims 1 to 3, characterized in that, The preset acceptance criteria include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and the coupling dose. Entering the target coupling dose window and the break coincidence coefficient The fracture acceptance criteria are met; the invalid reason code R at least distinguishes between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; the data processing unit, after summarizing the candidate adjustment items corresponding to the invalid reason code R, generates only one version of the next test condition. The next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation starting point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

5. The tensile hydrogen embrittlement assessment device with local hydrogen input correction according to claim 1, characterized in that, The fracture receiving area The effective exposure domain The boundaries of the pre-defined outward expansion distance, notch influence zone, finite element high-stress zone, digital image correlation high-strain zone, or weld heat-affected zone are determined; the fracture coincidence coefficient is mentioned. Falling into the fracture receiving area according to the fracture trajectory The length of the fracture trajectory is determined by the proportion of the fracture length to the total length of the fracture trajectory, the proportion of the fracture surface projection area, or the location of the fracture center.

6. A method for assessing tensile hydrogen embrittlement with local hydrogen input correction, characterized in that, The tensile hydrogen embrittlement assessment apparatus using local hydrogen input correction as described in any one of claims 1 to 5 comprises: S1. Prepare a tensile specimen. A local window is formed on the surface of the tensile specimen through the local window forming structure to define the effective exposure area. And record the window number and window position; S2. Determine the effective exposure area. and its effective exposure area ; S3. Establish a local hydrogen input unit using the sample number and the window number as indexes; S4. Perform pilot calibration, determine background stability based on background current, and use the coupling dose of the reference local hydrogen input unit. Establish a target-coupled dose window centered on the target; S5. Conduct in-situ local hydrogen permeation and slow strain rate tensile synchronous test, and synchronously acquire oxidation side current, background current, tensile load, strain, fracture time and fracture location through the synchronous acquisition unit. S6. Based on the effective exposure area Stress participation factor in the internal stress state calculation window And calculate the load participation function based on the load stage. ; S7. Obtain the background-corrected hydrogen permeation current based on the oxidation-side current and the background current, and then determine the background-corrected hydrogen permeation current based on the effective exposure area. Calculate the area-normalized hydrogen flux and the area-normalized hydrogen flux The window stress participation factor and the load participation function Integrating the product over the effective test period yields the coupling dose. ; S8. Determine the fracture acceptance zone And based on the fracture trajectory and the fracture receiving area Calculation of the degree of overlap and the breakage overlap coefficient ; S9. Perform effectiveness acceptance based on preset acceptance conditions, including the target coupling dose window, generate an effectiveness flag V, and write an invalidity reason code R if the acceptance fails and generate the next test condition version. ; S10. Calculate the hydrogen embrittlement evaluation quantity for local hydrogen input units that are marked as valid by validity marker V.

7. The method for assessing tensile hydrogen embrittlement with local hydrogen input correction according to claim 6, characterized in that, In step S6, the window stress participation coefficient is calculated. At that time, first target the effective exposure domain. The equivalent stress within the range is averaged by area, and then normalized using the maximum area-averaged equivalent stress of the same batch comparison window, so that... ; Calculate the load participation function The value is determined by the ratio of the cumulative maximum load up to the current moment to the peak load of this test. It is kept at 1 after the peak load is reached until the fracture. It is taken as 0 before the joint triggering moment of electrochemical detection and tensile loading, after the fracture, or when the time synchronization is not qualified.

8. The method for assessing tensile hydrogen embrittlement with local hydrogen input correction according to claim 6, characterized in that, In S4, the target coupling dose window is established according to the window position or window type, and locked before the formal test, and is not modified in reverse according to the sample to be evaluated after the test; the calibration results of the pilot calibration are written into the test condition version along with the window conditions.

9. The method for assessing tensile hydrogen embrittlement with local hydrogen input correction according to any one of claims 6 to 8, characterized in that, In S9, the preset acceptance conditions include background current stability, consistency of effective exposure area before and after the test, effectiveness of data acquisition time synchronization, and the coupling dose. Entering the target coupling dose window and the break coincidence coefficient The fracture acceptance criteria are met; the invalid reason code R at least distinguishes between background non-compliance, area non-compliance, load synchronization non-compliance, coupling dose non-compliance, and fracture acceptance non-compliance; after summarizing the candidate adjustment items corresponding to the invalid reason code R, only one version of the next test condition is generated. The next test condition version This includes at least one of the following: replacing the seal, replacing the window, calibrating the synchronous acquisition trigger, adjusting the load participation starting point, adjusting the hydrogen charging current, or adjusting the hydrogen charging time.

10. The method for assessing tensile hydrogen embrittlement with local hydrogen input correction according to any one of claims 6 to 8, characterized in that, In step S10, the hydrogen embrittlement evaluation metric includes the hydrogen embrittlement loss rate. The hydrogen embrittlement loss rate The relative loss rate of reduction of area, elongation after fracture, or fracture displacement between the hydrogen-free control sample and the partially hydrogen-permeated sample; the hydrogen embrittlement evaluation metric also includes the sensitivity to unit coupled dose. This is used to compare the plasticity loss corresponding to a unit coupling permeation dose.

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