An electrochemical in-situ hydrogen charging fatigue test device suitable for strain control

Abstract

The utility model discloses a kind of electrochemical in-situ hydrogen charging fatigue test devices suitable for strain control, comprising: hydrogen charging container, T-shaped rubber clamping body, two conical rubber clamping bodies, testing machine column and extensometer, hydrogen charging container is filled with electrolyte inside, first central hole and multiple electrode holes are set in top, second central hole is set in bottom, two through holes are set in side face along;T-shaped rubber clamping body is set on second central hole;Conical rubber clamping body is set on through hole, by T-shaped rubber clamping body, sample clamping end and the inner wall of second central hole are realized tight cooperation, avoid electrolyte leakage in test process, extensometer probe passes through conical rubber clamping body and sample working section direct contact, accurate collection sample deformation data in loading process, conical rubber clamping body separates the sensor part of extensometer from electrolyte, avoid electrolyte excretion and the interference of extensometer sensitive element, significantly improve the precision of test data.

Description

Technical Field

[0001] This utility model relates to the field of in-situ hydrogen charging test technology, specifically an electrochemical in-situ hydrogen charging fatigue test device suitable for strain control. Background Technology

[0002] Hydrogen energy, as a clean, efficient, and sustainable secondary energy source, has become a key breakthrough in solving the energy crisis and environmental pollution problems due to its unique physical and chemical properties. However, in the development and utilization of hydrogen energy, metal equipment such as high-pressure containers and transportation pipelines used for hydrogen storage are often directly subjected to cyclic loads or dynamic operating conditions. Under these circumstances, complex physicochemical reactions occur between the metal materials and hydrogen, leading to the deterioration of the material's mechanical properties and potentially even causing unexpected brittle fracture of the metal materials. This undoubtedly significantly increases the risk of equipment leakage and explosion.

[0003] Hydrogen-induced fatigue testing combines hydrogen charging with fatigue testing, allowing for real-time study of the dynamic interaction between stress field and hydrogen diffusion behavior. This more realistically reproduces the hydrogen-induced fatigue damage behavior of materials under actual service conditions, providing a scientifically sound technical means to analyze the degradation laws, microscopic failure mechanisms, and dynamic processes of metallic materials under hydrogen environments. Among these methods, electrochemical hydrogen charging offers numerous advantages, including rapid charging, simple operation, high safety, and environmental friendliness. It eliminates the need for complex high-pressure vessel systems, avoiding the sealing difficulties and explosion risks associated with high-pressure equipment. Furthermore, precise control of electrochemical parameters enables accurate adjustment and maintenance of hydrogen concentration, facilitating in-depth research into the hydrogen-induced fatigue damage behavior of metallic materials under different hydrogen concentrations.

[0004] However, existing in-situ electrochemical hydrogen-charged fatigue testing devices are mostly suitable for load-controlled (stress fatigue) conditions. Although they can provide a fatigue performance testing environment under electrochemical hydrogen-charged conditions by inserting the sample into the hydrogen-charged container and using the electrolyte and electrode rods inside, the electrolyte can easily corrode the metal components of the extensometer, such as the extensometer sensor, directly leading to a decrease in the extensometer's sensitivity. This affects the real-time performance and accuracy of strain signal control. Furthermore, the electric field and current during in-situ hydrogen charging may form stray loops with the extensometer's metal components, causing electrochemical interference that is superimposed on the strain signal, thus interfering with the control system's judgment of the true strain. Therefore, existing in-situ electrochemical hydrogen-charged fatigue testing devices cannot directly insert the extensometer probe into the hydrogen-charged container and make direct contact with the working section of the sample. Consequently, the range of strain control cannot be completely limited to the hydrogen-charged area, affecting the accuracy of the test results. Utility Model Content

[0005] The purpose of this invention is to provide an electrochemical in-situ hydrogen-charged fatigue testing device suitable for strain control, which can accurately collect deformation data of the sample during the loading process under hydrogen loading environment and realize strain-controlled loading, significantly improving the accuracy and reliability of the test data.

[0006] The technical solution of this utility model is: An electrochemical in-situ hydrogen-charged fatigue testing device suitable for strain control includes: a hydrogen-charging container, which is a transparent cylindrical shell with an internal cavity for filling with NaOH electrolyte; a first central hole and a second central hole for inserting a sample are respectively formed at the center of the top and bottom circular end faces of the hydrogen-charging container; two clamping ends of the sample are located in the first and second central holes respectively, and the second central hole and the clamping ends of the sample are sealed by a sealing element; the working section of the sample is located within the cavity of the hydrogen-charging container; and multiple electrode holes are also formed at the top of the hydrogen-charging container, with an electrode inserted into each electrode hole. The hydrogen filling container is equipped with a graphite rod, and two through holes spaced 25 mm apart are opened on its side along its height direction. The sealing element is a T-shaped rubber clamp body, which is set on the second central hole. It includes a disk and a cylinder vertically connected to the center of the disk. The T-shaped rubber clamp body also includes a through hole that penetrates the cylinder and the disk along the central axis of the cylinder. The outer surface of the cylinder is sealed to the channel of the second central hole, which can effectively prevent electrolyte leakage along the wall of the central hole at the bottom of the container. The through hole is used to clamp the sample, which can fix the sample and prevent electrolyte leakage along the sample. The diameter of the first central hole is larger than the diameter of the sample clamping end to ensure that the axial deformation of the sample during loading is not constrained by the hydrogen filling container. Two conical rubber clamps are correspondingly disposed on the through hole. Each conical rubber clamp includes: a first cylindrical section, externally sealed to the inner wall of the through hole, and internally having a first circular channel along its axial direction. The outer diameter of the first cylindrical section is slightly larger than the diameter of the orifice of the through hole on the outer wall of the hydrogen filling container, so that its outer surface fits tightly against the inner surface of the orifice of the through hole on the outer wall of the hydrogen filling container. The inner diameter of the first circular channel is larger than the probe diameter of the extensometer. Sufficient space is reserved to ensure that the two probes move relatively with the deformation of the sample during the test, avoiding the obstruction of probe movement due to insufficient orifice space. This can affect measurement or control accuracy. The second cylindrical section has a smaller diameter than the first cylindrical section, and an axial second circular channel is formed inside. The inner wall of the second circular channel is sealed to the outer surface of the probe. The diameter of the second circular channel is slightly smaller than the probe diameter of the extensometer, so that the rubber tightly wraps around the probe, preventing electrolyte leakage along the probe. The conical section has a conical channel inside, with the smaller diameter end connecting to the second circular channel and the larger diameter end connecting to the first circular channel. The extensometer is fixed to the testing machine column by an extensometer bracket and is located on one side of the hydrogen filling container. The probes are respectively inserted into corresponding conical rubber clamps, and the ends of the two probes are in contact with the surface of the middle gauge section of the sample in the cavity. All probes are made of ceramic.

[0007] Furthermore, in order to ensure uniform hydrogen concentration on the outer surface of the sample, the plurality of electrode holes are arranged in a ring array with the first central hole as the center, and an electrode clamp is held on the graphite rod, the electrode clamp being connected to the anode of the power supply.

[0008] Furthermore, the hydrogen filling container is provided with a solution injection port at the top to facilitate the injection of electrolyte.

[0009] Furthermore, the extensometer support includes: a support plate, one end of which is mounted on the test machine column via a connector, and the other end has two slots for the probe of the extensometer to pass through; bolt holes are provided near the center of the plate surface; two spring steel plates, one end of which is fixed to the bolt holes by first bolts, and the other end of which presses against the extensometer. A washer is provided between the first bolts and the bolt holes.

[0010] Furthermore, the connecting component includes: a vertical adjustment component, comprising a fixing block sleeved on the column of the testing machine, the fixing block comprising two symmetrically arranged clamping blocks, each clamping block having multiple first threaded holes, each first threaded hole being equipped with a second bolt, the two clamping blocks being connected by the second bolt; and a horizontal adjustment component, comprising a second threaded hole, a slotted hole, and a screw, the second threaded hole being located on the side of the two clamping blocks that are far apart from each other, the second threaded hole being adapted to the second bolt, the slotted hole being located on the surface of the support plate, the slot of the slotted hole being aligned with the length direction of the support plate, the second bolt passing through the slotted hole and being tightened in the second threaded hole, the nut of the second bolt being abutted against the surface of the support plate.

[0011] Furthermore, the sides of the two clamping blocks that are close to each other are in contact with the outer peripheral surface of the test machine column.

[0012] Furthermore, the outer diameter of the cylinder of the T-shaped rubber clamp is slightly larger than the diameter of the second central hole, so that the outer surface of the cylinder can fit tightly against the inner wall of the second central hole. The inner diameter of the through hole of the T-shaped rubber clamp is slightly smaller than the diameter of the clamping section of the sample, so that the clamping section of the sample can pass through the through hole and the clamping section fits tightly with the through hole. During the hydrogen charging process, on the one hand, it can effectively restrain the shaking or displacement of the hydrogen charging container during the test, ensuring the stability of the hydrogen charging test environment; on the other hand, it can form a double sealing effect, preventing electrolyte leakage along the gap between the sample clamping end and the through hole of the T-shaped rubber clamp, and also preventing electrolyte leakage downward along the gap between the cylinder of the T-shaped rubber clamp and the inner wall of the second central hole.

[0013] Furthermore, the conical section adopts a corrugated structure. This effectively weakens the constraint force exerted on the probe by the conical rubber clamp during cyclic loading, ensuring that the two probes can move freely relative to each other when performing deformation measurement or strain control.

[0014] Compared with the prior art, the beneficial effects of this utility model are: This invention utilizes a transparent hydrogen-filling container to perform hydrogen filling operations on the sample, allowing clear observation of the hydrogen filling process and the dynamic progress of sample changes. This provides intuitive evidence for in-depth research into the low-cycle fatigue damage behavior of materials in hydrogen-exposed environments, and is more suitable for practical engineering applications. The T-shaped rubber clamp ensures a seamless and tight fit between the clamping end of the fatigue sample and the inner wall of the second central hole, effectively preventing electrolyte leakage during the test. This ensures the stability of the hydrogen concentration in the test environment, avoids fluctuations in test environment parameters caused by electrolyte leakage, and prevents corrosion of other components. Simultaneously, this invention employs an external extensometer. By passing the extensometer probe through the channel of the conical rubber clamp and directly contacting the surface of the working section of the sample in the electrolyte, it accurately collects deformation data of the sample during loading and achieves strain-controlled cyclic loading. Meanwhile, the conical rubber clamp can isolate the sensor part of the extensometer from the electrolyte, effectively avoiding the interference of the electrolyte on the sensitive element of the extensometer and the problem of electrolyte leakage, thereby preventing it from having an adverse effect on the strain test results and control accuracy of the extensometer, and significantly improving the accuracy of the test data.

[0015] The hydrogen filling container of this invention features multiple electrode holes evenly distributed around a central hole on its top. An anode graphite rod is inserted into each electrode hole, and each graphite rod is connected in parallel to the anode of a DC power supply via electrode clamps. This design enables uniform hydrogen filling of all areas of the sample surface, effectively reducing the dispersion of test results caused by poor hydrogen filling, thereby improving the reliability and comparability of the test results. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0017] Figure 2 This is a schematic diagram of the internal structure of the hydrogen filling container of this utility model.

[0018] Figure 3 This is a schematic diagram of the hydrogen filling container structure of this utility model.

[0019] Figure 4 This is a schematic diagram of the T-shaped rubber clamping body structure of this utility model.

[0020] Figure 5 This is a schematic diagram of the external structure of the conical rubber clamp of this utility model.

[0021] Figure 6 This is a cross-sectional view of the internal structure of the conical rubber clamp of this utility model.

[0022] Figure 7 This is a schematic diagram of the support plate and spring steel sheet structure of this utility model.

[0023] Figure 8This is a schematic diagram of the support plate structure of this utility model; Figure 9 This is a schematic diagram of the fixing block structure of this utility model; Figure 10 for Figure 8 Schematic diagram of the assembly direction of the central fixed block.

[0024] Among them, 1. Sample, 2. Graphite rod, 3. Electrode clamp, 4. Hydrogen filling container, 5. T-shaped rubber clamp, 6. Conical rubber clamp, 7. Extensometer, 8. Spring steel sheet, 9. First bolt, 10. Extensometer bracket, 11. Second bolt, 12. Gasket, 13. Clamping block, 14. Testing machine column; 4-1. First central hole, 4-2. Solution injection hole, 4-3. Electrode hole, 4-4. Through hole, 4-5. Second central hole, 5-1. Cylinder, 5-2. Through hole, 6-1. Cylinder, 6-2. First circular channel, 6-3. Second circular channel, 10-1. Channel, 10-2. Bolt hole, 10-3. Slotted hole, 13-1. First threaded hole, 13-2. Second threaded hole. Detailed Implementation

[0025] The following is combined with Figures 1 to 10 The specific embodiments of this utility model will be described in detail below. In the description of this utility model, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0026] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0027] It should be noted that the circuit connections involved in this utility model all adopt conventional circuit connection methods and do not involve any innovation.

[0028] Example like Figure 1 As shown, an electrochemical in-situ hydrogen-charging fatigue testing device suitable for strain control includes: a hydrogen-charging container 4, a sealing element, two conical rubber clamps 6, and an extensometer 7, as shown. Figure 1 , Figure 2 and Figure 3 As shown, the hydrogen filling container 4 is a transparent cylindrical shell with an internal cavity to be filled with NaOH electrolyte. A first central hole 4-1 and a second central hole 4-5 for inserting the sample 1 are respectively opened at the center of the top circular end face and the center of the bottom circular end face of the hydrogen filling container 4. The two clamping ends of the sample 1 are located in the first central hole 4-1 and the second central hole 4-5, respectively, and the second central hole 4-5 and the clamping ends of the sample 1 are sealed by a sealing element. The working section of the sample 1 is located inside the cavity of the hydrogen filling container 4. Multiple electrode holes 4-3 are also opened at the top of the hydrogen filling container 4, and a graphite rod 2 is inserted into each electrode hole 4-3. Two through holes 4-4 with a spacing of 25 mm are opened on the side of the hydrogen filling container 4 along its height direction; Figure 2 As shown, the sealing element is a T-shaped rubber clamp 5, which is disposed on the second central hole 4-5. It includes a disk and a cylinder 5-1 vertically connected to the center of the disk. The T-shaped rubber clamp 5 also includes a through hole 5-2 extending through the cylinder 5-1 and the disk along the central axis of the cylinder 5-1. The outer surface of the cylinder 5-1 is sealed to the channel of the second central hole 4-5, effectively preventing electrolyte leakage along the wall of the central hole at the bottom of the container. The through hole 5-2 is used to clamp the clamping end of the sample 1, fixing the sample 1 and preventing electrolyte leakage along the sample. The diameter of the first central hole 4-1 is larger than the diameter of the clamping end of the sample 1 to ensure that the axial deformation of the sample 1 during loading is not constrained by the hydrogen-filled container 4. Figure 3 As shown, two conical rubber clamps 6 are correspondingly disposed on the through hole 4-4. Each conical rubber clamp 6 includes: a first cylindrical section, a conical section, and a second cylindrical section connected in sequence. The second cylindrical section and the conical section pass through the through hole 4-4 and are located inside the hydrogen filling container 4. The conical section can contract and stretch. The outer side of the first cylindrical section is sealed to the inner wall of the through hole 4-4. A first circular channel 6-2 is opened along its axial direction inside. The outer diameter of the first cylindrical section 6-1 is slightly larger than the diameter of the orifice of the through hole 4-4 on the outer wall of the hydrogen filling container 4, so that its outer surface is tightly fitted to the inner surface of the orifice of the through hole 4-4 on the outer wall of the hydrogen filling container 4. The inner diameter of the first circular channel 6-2 is larger than the probe of the extensometer 7. The needle diameter; to ensure sufficient space for the relative movement of the two probes with the deformation of sample 1 during the test, and to avoid hindering the movement of the probes due to insufficient aperture space, thereby affecting the measurement or control accuracy; the diameter of the second cylindrical section is smaller than that of the first cylindrical section, and a second circular channel 6-3 is opened inside along its axial direction. The inner wall of the second circular channel 6-3 is sealed to the outer side of the probe. The aperture of the second circular channel 6-3 is slightly smaller than the probe diameter of the extensometer 7, so that the rubber tightly wraps the probe of the extensometer and prevents the electrolyte from leaking along the probe of the extensometer 7; a tapered channel is opened inside the tapered section, with the smaller aperture end connected to the second circular channel 6-3 and the larger aperture end connected to the first circular channel 6-2; such as Figure 1As shown, the testing machine column 14 is located on one side of the hydrogen filling container; the extensometer 7 is fixed to the testing machine column 14 via the extensometer bracket 10 and is located on one side of the hydrogen filling container, as shown. Figure 2 As shown, the probes are respectively inserted into the corresponding conical rubber clamps 6, and the ends of the two probes are in contact with the surface of the middle gauge section of the sample 1 in the cavity. It is worth noting that the probes in this embodiment are all made of ceramic. By using an external method for the key components of the extensometer, only the ends of the two ceramic probes of the extensometer 7 are in contact with the effective working section of the sample 1. This eliminates the need to consider the interference and corrosion of the electrolyte on the control accuracy of the extensometer 7, and also ensures that the strain control range is completely limited to the hydrogen-filled area, making the test results more accurate and reasonable.

[0029] In some embodiments, such as Figure 3 As shown, in order to ensure uniform hydrogen concentration on the outer surface of sample 1, multiple electrode holes 4-3 are arranged in a ring array with the first central hole 4-1 as the center. Electrode clamps 3 are held on graphite rod 2 and connected to the anode of power supply.

[0030] like Figure 3 As shown, the top of the hydrogen charging container is equipped with a solution injection port 4-2 to facilitate the injection of electrolyte.

[0031] like Figure 7 and Figure 8 As shown, the extensometer bracket 10 includes a support plate and two spring steel plates 8. One end of the support plate is mounted on the test machine column 14 via a connector, and the other end has two channels 10-1 for the probes of the extensometer 7 to pass through. Bolt holes 10-2 are provided near the center of the plate surface. One end of each of the two spring steel plates 8 is fixed to the bolt holes 10-2 by a first bolt 9, and the other end presses against the extensometer 7. A washer 12 is provided between the first bolt 9 and the bolt holes 10-2.

[0032] like Figure 9 and Figure 10 As shown, the connecting parts include: a vertical adjustment part and a horizontal adjustment part. The vertical adjustment part includes a fixing block, which is sleeved on the column 14 of the testing machine. The fixing block includes two symmetrically arranged clamping blocks 13. Each clamping block 13 has multiple first threaded holes 13-1. Each first threaded hole 13-1 is equipped with a second bolt 11. The two clamping blocks 13 are connected by the second bolt 11. The horizontal adjustment part includes a second threaded hole 13-2, a slotted hole 10-3 and a screw. The second threaded hole 13-2 is opened on the side of the two clamping blocks 13 that is far away from each other. The second threaded hole 13-2 is adapted to the second bolt 11. The slotted hole 10-3 is opened on the plate surface of the support plate. The channel of the slotted hole 10-3 is consistent with the length direction of the support plate. The second bolt 11 passes through the slotted hole 10-3 and is tightened in the second threaded hole 13-2. The nut of the second bolt 11 abuts against the plate surface of the support plate.

[0033] like Figure 1 As shown, the sides of the two clamping blocks 13 that are close to each other are in contact with the outer peripheral surface of the test machine column 14.

[0034] In some embodiments, the outer diameter of the cylinder 5-1 of the T-shaped rubber clamp 5 is slightly larger than the diameter of the second central hole, so that the outer surface of the cylinder 5-1 can fit tightly against the inner wall of the second central hole 4-5. The inner diameter of the through hole 5-2 of the T-shaped rubber clamp 5 is slightly smaller than the diameter of the clamping section of the sample 1, so that the clamping section of the sample 1 can pass through the through hole 5-2 and the clamping section fits tightly against the through hole 5-2. During the hydrogen charging process, on the one hand, it can effectively restrain the shaking or displacement of the hydrogen charging container 4 during the test, ensuring the stability of the hydrogen charging test environment; on the other hand, it can form a double sealing effect, preventing the electrolyte from leaking along the gap between the clamping end of the sample 1 and the through hole 5-2 of the T-shaped rubber clamp 5, and also preventing the electrolyte from seeping downwards along the gap between the cylinder 5-1 of the T-shaped rubber clamp 5 and the inner wall of the second central hole 4-5.

[0035] like Figure 5 and Figure 6 As shown, the conical section adopts a corrugated structure. This effectively weakens the constraint force generated by the six pairs of probes in the conical rubber clamp during cyclic loading, ensuring that the two probes can move freely relative to each other when performing deformation measurement or strain control.

[0036] When using: Insert the lower clamping section of sample 1 into the through hole 5-2 of the T-shaped rubber clamp 5. Adjust the position so that the T-shaped rubber clamp 8 tightly grips the clamping section of sample 1. Then, insert the entire T-shaped rubber clamp 8 into the second central hole 4-5 on the bottom surface of the hydrogen filling container 4 and extend it out from the first central hole 4-1 on the top surface. Squeeze the T-shaped rubber clamp 5 into the second central hole 4-5 as well, ensuring that the outer surface of the cylindrical body 5-1 of the T-shaped rubber clamp 5 is tightly fitted to the inner wall of the second central hole 4-5. Insert four graphite rods 2 into the hydrogen filling container 4 through the electrode holes 4-3. The length of the graphite rods 2 should be slightly greater than the height of the hydrogen filling container 4 to facilitate reliable connection with the electrode clamps 3.

[0037] The assembled hydrogen filling container 4 and sample 1 are placed on the testing machine, and the hydraulic pump of the testing machine clamps is operated to clamp the clamping sections at both ends of sample 1.

[0038] Adjust the two clamping blocks 13 to a suitable height position on the test machine column 14 to facilitate the installation of the extensometer 7, and screw the second bolt 11 into the corresponding threaded hole 13-1. The second bolt 11 is an internal hexagon countersunk bolt. Tighten and fix the two clamping blocks 13 to the test machine column 14.

[0039] Align the reserved hole of the spring steel sheet 8 with the bolt hole 10-2 of the extensometer bracket 10, and fix it to the extensometer bracket 10 with the first bolt 9. Then align the slotted hole 10-3 of the extensometer bracket 10 with the second threaded hole 13-2 on the clamping block 13, adjust the lateral position of the extensometer bracket 10, and fix the extensometer bracket 10 to the clamping block 13 by screwing the second screw 11 into the second threaded hole 13-2.

[0040] Insert the two probes of the extensometer 7 through the conical rubber clamp 6 and adjust them to a suitable position, ideally with the corrugated section in a freely elongated state after installation. Insert the two probes of the extensometer 7 into the through-hole 4-4 on the side wall of the hydrogen filling container 4, so that the probe tips contact the outer surface of the working section of the sample 1. At the same time, squeeze the conical rubber clamp 6 into the through-hole 4-4 of the hydrogen filling container 4 to ensure a tight fit. Fine-tune the distance between the two probes of the extensometer to achieve the initial error range, and pull the spring plate 8 to press the extensometer 7, ensuring that the probe tips are in stable contact with the surface of the working section of the sample 1.

[0041] Using a conduit or syringe, inject the pre-prepared electrolyte through the solution injection port 4-2 of the hydrogen filling container 4.

[0042] The graphite rod 3 is connected in series with the anode of the DC power supply using electrode clamp 3 and wires, while the sample 1 is connected to the cathode of the DC power supply.

[0043] Set the fatigue test parameters and DC power supply current, and start the test.

[0044] The procedure for removing the device after the test is as follows: Turn off the DC power supply, use a syringe to draw out the electrolyte in the hydrogen charging container 4 through the solution injection hole 4-2, pry open the spring steel plate 8, pull out the conical rubber clamp 6, and remove the extensometer 7. Loosen the upper and lower clamps of the testing machine and remove the remaining parts as a whole.

[0045] Remove the electrode clips 3 from sample 1 and graphite rod 2, and remove the graphite carbon rod.

[0046] Release the T-shaped rubber clamp 5 and remove sample 1.

[0047] The above-disclosed embodiments are merely preferred embodiments of the present invention. However, the embodiments of the present invention are not limited thereto, and any variations that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. An electrochemical in-situ hydrogen charging fatigue testing apparatus suitable for strain control, characterized by, include: The hydrogen filling container (4) is a transparent cylindrical shell with an internal cavity. The top center and bottom center of the hydrogen filling container (4) are respectively provided with a first central hole (4-1) and a second central hole (4-5) for inserting the sample (1). The two clamping ends of the sample (1) are located in the first central hole (4-1) and the second central hole (4-5) respectively. The second central hole (4-5) and the clamping ends of the sample (1) are sealed by a sealing element. The working section of the sample (1) is located in the cavity of the hydrogen filling container (4). The top of the hydrogen filling container (4) is also provided with a solution injection hole (4-2) and multiple electrode holes (4-3). A graphite rod (2) is inserted into each electrode hole (4-3). Two through holes (4-4) are opened on the side of the hydrogen filling container (4) along its height direction. Two conical rubber clamps (6) are correspondingly disposed on the through hole (4-4). Each conical rubber clamp (6) includes: a first cylindrical section, which is externally sealed to the inner wall of the through hole (4-4) and has a first circular channel (6-2) opened along its axial direction; a second cylindrical section, which has a diameter smaller than that of the first cylindrical section and has a second circular channel (6-3) opened along its axial direction; and a conical section that can be folded and stretched. The conical section has a conical channel opened inside, with the smaller diameter end connected to the second circular channel (6-3) and the larger diameter end connected to the first circular channel (6-2). The extensometer (7) is fixed on the test machine column (14) of the test machine by the extensometer bracket (10). The probes of the extensometer (7) are respectively inserted into the corresponding conical rubber clamps (6). The outer side of the probe is sealed to the inner wall of the second circular channel (6-3), and the ends of the two probes are in contact with the working section surface of the sample (1).

2. The electrochemical in-situ hydrogen charging fatigue testing device suitable for strain control according to claim 1, wherein, The sealing element is a T-shaped rubber clamp (5), which is disposed on the second central hole (4-5) and includes a disk and a cylinder (5-1) vertically connected to the center of the disk. The T-shaped rubber clamp (5) also includes a through hole (5-2) through the cylinder (5-1) and the disk, which is opened along the central axis of the cylinder (5-1). The outer surface of the cylinder (5-1) is sealed to the channel of the second central hole (4-5). The through hole (5-2) is used to clamp the clamping end of the sample (1).

3. The electrochemical in-situ hydrogen charging fatigue testing device suitable for strain control according to claim 2, characterized in that, The outer diameter of the cylinder (5-1) of the T-shaped rubber clamp (5) is slightly larger than the diameter of the second central hole (4-5) so that the outer surface of the cylinder (5-1) can fit tightly with the inner wall of the second central hole (4-5). The inner diameter of the through hole (5-2) of the T-shaped rubber clamp (5) is slightly smaller than the diameter of the clamping section of the sample (1) so that the clamping section of the sample (1) can pass through the through hole (5-2) and the clamping section fits tightly with the through hole (5-2).

4. The electrochemical in-situ hydrogen charging apparatus for strain control according to claim 1, wherein Multiple electrode holes (4-3) are arranged in a ring array with the first central hole (4-1) as the center. An electrode clamp (3) is held on the graphite rod (2), and the electrode clamp (3) is connected to the anode of the power supply.

5. The electrochemical in-situ hydrogen charging apparatus for strain control according to claim 1, wherein The extensometer bracket (10) includes: The support plate is mounted on the column (14) of the testing machine at one end via a connector, and has two slots (10-1) at the other end for the probe of the extensometer (7) to pass through. The plate surface is provided with bolt holes (10-2) near the middle position. Two spring steel plates (8) are fixed at one end to the bolt hole (10-2) by the first bolt (9) and at the other end to the extensometer (7).

6. The electrochemical in-situ hydrogen charging apparatus for strain-controlled fatigue test according to claim 5, wherein The connector includes: The vertical adjustment component includes a fixing block, which is sleeved on the column (14) of the testing machine. The fixing block includes two symmetrically arranged clamping blocks (13). Each clamping block (13) has multiple first threaded holes (13-1). Each first threaded hole (13-1) is equipped with a second bolt (11). The two clamping blocks (13) are connected by the second bolt (11). The lateral adjustment component includes a second threaded hole (13-2), a slotted hole (10-3), and a screw. The second threaded hole (13-2) is located on the side of the two clamping blocks (13) that are far apart from each other. The second threaded hole (13-2) is adapted to the second bolt (11). The slotted hole (10-3) is located on the plate surface of the support plate. The channel of the slotted hole (10-3) is aligned with the length direction of the support plate. The second bolt (11) passes through the slotted hole (10-3) and is tightened in the second threaded hole (13-2). The nut of the second bolt (11) abuts against the plate surface of the support plate.

7. The electrochemical in-situ hydrogen charging apparatus for strain-controlled fatigue test according to claim 6, wherein The two clamping blocks (13) are close to each other on one side and are in contact with the outer peripheral surface of the test machine column (14).

8. The electrochemical in-situ hydrogen charging apparatus for strain-controlled fatigue test according to claim 1, wherein The tapered section adopts a corrugated structure.

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