In-situ hydrogen charging test device and test method for assisting axial strain

Abstract

The invention provides an in-situ hydrogen filling test device and test method for assisting axial strain, and belongs to the technical field of in-situ hydrogen filling detection, and the in-situ hydrogen filling test device comprises an in-situ hydrogen filling box and a test adjusting mechanism. A hollow cavity is formed in the in-situ hydrogen filling box, a sample longitudinally penetrates through the in-situ hydrogen filling box, the in-situ hydrogen filling box has deformation in the height direction along with axial strain of the sample, a displacement sensor used for detecting the displacement amount of the in-situ hydrogen filling box in the height direction is arranged outside the in-situ hydrogen filling box, and a platinum sheet electrode is arranged at the top of the in-situ hydrogen filling box. The lower end of the platinum sheet electrode penetrates into the hollow cavity, and an acid reaction solution is injected into the in-situ hydrogen filling tank; the test adjusting mechanism comprises a lifting assembly and a transverse moving assembly. According to the in-situ hydrogen charging test device for assisting the axial strain, provided by the invention, in-situ hydrogen charging is carried out on a sample, meanwhile, the device can adapt to various axial strain tests, and the mechanical property condition of a material in a real environment can be reflected.

Description

Technical Field

[0001] The present invention belongs to the technical field of in-situ hydrogen charging detection, and more specifically, relates to an in-situ hydrogen charging test device and a test method for assisting axial strain. Background Art

[0002] Metal materials used in the oil and gas industry often encounter challenges from high temperature and high pressure environments, as well as erosion from corrosive gases containing large amounts of CO2 and H2S. This acidic gas can easily cause hydrogen embrittlement (HE) in metal materials, causing them to become brittle and thus reducing their service life. Therefore, in a hydrogen-containing environment, it can cause irreversible damage to metal materials and may also cause significant losses. Hydrogen embrittlement refers to the brittle fracture of metals below their yield strength after they have served in a specific service environment for a period of time. Hydrogen embrittlement is usually the result of the combined action of force and hydrogen. Once hydrogen embrittlement occurs, it cannot be eliminated, and there is often no warning before hydrogen embrittlement fracture. Therefore, once hydrogen embrittlement failure occurs, it will have extremely serious consequences.

[0003] At present, most of the research on hydrogen embrittlement mainly conducts electrochemical hydrogen charging or gas phase hydrogen charging experiments in advance and then conducts mechanical property tests. However, this does not match the actual use of metals. In practical applications, most metal materials are subject to stress and premature failure of materials occurs under the interaction of stress and hydrogen. The theory obtained by this pre-hydrogenation study of the mechanical properties of materials is inconsistent with the actual situation. At present, this type of in-situ hydrogen charging of the specimen can only be used in conjunction with a uniaxial tensile testing machine and has many defects and insecurities. Summary of the invention

[0004] The purpose of the present invention is to provide an in-situ hydrogen charging test device for assisting axial strain, which can realize in-situ hydrogen charging of samples and can be adapted to various axial strain tests at the same time, and can reflect the mechanical properties of materials in real environments.

[0005] To achieve the above object, the technical solution adopted by the present invention is: to provide an in-situ hydrogen charging test device for assisting axial strain, comprising: An in-situ hydrogen charging box, wherein the in-situ hydrogen charging box has a hollow chamber inside, a sample is longitudinally penetrated by the in-situ hydrogen charging box, the sample is respectively sealed with the top and bottom of the in-situ hydrogen charging box through a sealing assembly, the in-situ hydrogen charging box has a height deformation with the axial strain of the sample, a displacement sensor for detecting the height displacement of the in-situ hydrogen charging box is arranged on the outside of the in-situ hydrogen charging box, a platinum electrode is arranged on the top of the in-situ hydrogen charging box, the lower end of the platinum electrode penetrates into the hollow chamber, an acidic reaction solution is filled in the in-situ hydrogen charging box, and the platinum electrode is electrically connected to the sample so that the acidic reaction solution reacts to simulate the in-situ hydrogen charging environment in the hollow chamber; A test adjustment mechanism, the test adjustment mechanism includes a lifting assembly and a transverse movement assembly, the transverse movement assembly includes a screw transmission member and a screw drive member, the in-situ hydrogen filling box is installed on the screw transmission member through a horizontal support frame, and the screw drive member drives the screw transmission member to drive the in-situ hydrogen filling box to move laterally; the lifting assembly includes two hydraulic support frames and a hydraulic drive member, the two hydraulic support frames are both longitudinally arranged and spaced from each other, the upper end of the hydraulic support frame is provided with a lifting drive end, the two ends of the screw transmission member are respectively rotatably arranged on the two lifting drive ends, the screw drive member is arranged on any of the lifting drive ends, the hydraulic drive member is arranged on the outside of any of the hydraulic support frames, an electromagnetic switch for controlling the hydraulic distribution is arranged between the hydraulic drive member and the two hydraulic support frames, and the hydraulic drive member drives the two lifting drive ends to rise and fall synchronously to drive the in-situ hydrogen filling box to move longitudinally.

[0006] In a possible implementation, the in-situ hydrogen filling box includes: A telescopic box, wherein the middle part of the outer peripheral wall of the telescopic box is provided with an axial folding structure, the top of the telescopic box is provided with an open end, the top of the outer wall of the telescopic box is provided with a mounting plate extending outward, the displacement sensor is provided on the mounting plate, the lower end of the sample passes through the bottom of the telescopic box, and the horizontal support frame is clamped on the bottom circumference of the in-situ hydrogen charging box; A box cover is sealed and installed at the open end of the telescopic box body, the platinum sheet electrode longitudinally penetrates the box cover and extends to the interior of the telescopic box body, and the upper end of the sample penetrates the box cover.

[0007] In a possible implementation, a drain valve is provided at the bottom of the telescopic box, a plurality of vent holes are arranged side by side at the top of the box cover, and sodium bicarbonate particles are provided in the vent holes.

[0008] In a possible implementation, the sealing assembly includes: An inner sealing sleeve, the inner sealing sleeve being arranged on the outer periphery of the root of the gauge length deformation section of the sample; Two sub-clamps, the two sub-clamps are arranged horizontally opposite to each other, the opposite ends of the sub-clamps are provided with longitudinally bent clamping plates, the two clamping plates are respectively clamped on both sides of the inner sealing sleeve, and the sub-clamps are connected to the upper end surface of the in-situ hydrogen charging box or the lower end surface of the in-situ hydrogen charging box; An outer sealing sleeve is sleeved on the outer periphery of the two clamping plates.

[0009] In a possible implementation, a first hydraulic cylinder is provided at the lower portion of the hydraulic support frame, a first hydraulic chamber filled with hydraulic oil is provided in the first hydraulic cylinder, a first piston is provided at the top sliding seal of the first hydraulic chamber, a hydraulic rod is vertically provided at the upper end surface of the first piston, and the lifting drive end is correspondingly provided at the upper end of the hydraulic rod; the hydraulic drive component includes a second hydraulic cylinder, a second hydraulic chamber filled with hydraulic oil is provided inside the second hydraulic cylinder, a second piston is provided at the top sliding seal of the second hydraulic chamber, a driving assembly is provided at the bottom of the second hydraulic chamber, the two first hydraulic chambers and the second hydraulic chambers are connected by a connecting pipe, and the driving assembly drives the second piston to rise and fall so that the hydraulic oil in the second hydraulic chamber enters or leaves the two first hydraulic chambers, so as to drive the two first pistons to drive the first hydraulic rod to rise and fall.

[0010] In a possible implementation, the driving component includes: A traction roller, the traction roller is located at the bottom of the second hydraulic chamber, a traction rope is wound around the traction roller, and the traction rope is connected to the second piston; A traction motor, wherein the traction motor is arranged outside the second hydraulic cylinder, and a driving end of the traction motor is connected to the traction roller through a coupling for driving the traction roller to rotate; A reset component is disposed in the second hydraulic chamber and between the second piston and the traction roller, and is used for driving the second piston moved to the lower part of the second hydraulic chamber to move upward and reset.

[0011] In a possible implementation, the resetting component includes: A limiting edge, the limiting edge is integrally formed in the circumference of the middle and lower part of the second hydraulic cavity and is located above the traction roller; A spring, wherein the lower end of the spring is arranged in the circumference of the limiting edge, and the spring is located below the second piston. The second piston moving to the lower part of the second hydraulic chamber compresses the spring, and the spring provides elastic force to drive the second piston to move upward and reset.

[0012] In a possible implementation, a hydrogen concentration sensor is provided at a lifting drive end of at least one of the hydraulic support frames, and the hydrogen concentration sensor is electrically connected to an alarm via a controller.

[0013] The beneficial effect of the in-situ hydrogen charging test device for assisting axial strain provided by the present invention is that: compared with the prior art, the sample is enclosed in the in-situ hydrogen charging box, the electromagnetic switch is turned on, and the hydraulic drive is used to drive the two lifting drive ends to synchronously lift and lower to drive the in-situ hydrogen charging box to move longitudinally, and then the electromagnetic switch is turned off, and the screw drive is used to drive the screw transmission to drive the in-situ hydrogen charging box to move laterally, so that the in-situ hydrogen charging box moves to a predetermined stretching position to adapt to various axial strain test devices. By electrically connecting the sample and the platinum electrode, the platinum electrode is used as the anode and the sample is used as the cathode, and the acidic reaction solution reacts in the hollow chamber to simulate the in-situ hydrogen charging environment, so that the sample can perform an axial strain test of the sample under the in-situ hydrogen charging environment. At the same time, when the sample is subjected to the axial strain test, the axial displacement of the sample is monitored in real time using a displacement sensor. In the in-situ hydrogen charging test device for assisting axial strain provided by the present invention, a device that realizes in-situ hydrogen charging of the sample and can adapt to various axial strain tests at the same time can reflect the mechanical properties of the material under a real environment.

[0014] The present invention also provides an in-situ hydrogen charging test method for assisting axial strain, using the in-situ hydrogen charging test device for assisting axial strain, comprising the following steps: S1: The sample was mechanically ground from #150 to #2000 using metallographic silicon carbide paper, cleaned and dried in ethanol solution, and installed in an in-situ hydrogen filling box; S2: Move the in-situ hydrogen charging box to a predetermined position by using the lifting assembly and the lateral movement assembly in the test adjustment mechanism, and wrap the portion of the sample located outside the in-situ hydrogen charging box with silica gel; S3: Inject the acidic reaction solution into the in-situ hydrogen charging box, connect the platinum electrode and the sample to a constant current power supply, use the platinum electrode as the anode and the sample as the cathode, and the acidic reaction solution reacts in the hollow chamber to simulate the in-situ hydrogen charging environment, and perform a tensile test on the sample at the same time; S4: The in-situ hydrogen charging box deforms in the height direction along with the axial strain of the sample. The displacement sensor detects the deformation amount of the in-situ hydrogen charging box in the height direction to obtain the axial strain amount of the sample in the in-situ hydrogen charging environment.

[0015] In a possible implementation, in step S3, when the acidic reaction solution is injected into the in-situ hydrogen charging box, the acidic reaction solution is a 0.5 mol / L H2SO4 solution, and 1 g / L thiourea is added simultaneously.

[0016] The beneficial effect of the in-situ hydrogen charging test method for assisting axial strain provided by the present invention is that: compared with the prior art, since the test method uses the above-mentioned in-situ hydrogen charging test device for assisting axial strain, it has the same beneficial effect as the in-situ hydrogen charging test device for assisting axial strain, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of the structure of the in-situ hydrogen charging box and the sample provided by the present invention when they are matched; Figure 2 for Figure 1 A partial enlarged view of the M in the middle; Figure 3 A top view of the in-situ hydrogen charging box and the sample provided by the present invention when they are matched; Figure 4 A schematic structural diagram of an in-situ hydrogen charging test device for assisting axial strain provided by the present invention; Figure 5 A flow chart of an in-situ hydrogen charging test method for assisting axial strain provided by the present invention.

[0019] In the figure: 1. sample; 2. telescopic box; 3. box cover; 4. displacement sensor; 5. platinum electrode; 6. acidic reaction solution; 7. mounting plate; 8. drain valve; 9. vent; 10. inner sealing sleeve; 11. sub-chuck; 12. clamping plate; 13. outer sealing sleeve; 14. first hydraulic cylinder; 15. first hydraulic chamber; 16. first piston; 17. second hydraulic cylinder; 18. second hydraulic chamber; 19. second piston; 20. connecting pipe; 21. traction roller; 22. traction rope; 23. traction motor; 24. limiting edge; 25. spring; 26. hydrogen concentration sensor; 27. horizontal support frame; 28. hydraulic rod; 29. ​​screw transmission; 30. screw drive; 31. electromagnetic switch; 32. level; 33. counterweight. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0021] Unless explicitly defined otherwise, the use of terms such as "first," "second," or "third," etc., are intended to distinguish different objects rather than to describe a specific order.

[0022] Unless otherwise expressly defined, directional words such as the terms "center", "lateral", "longitudinal", "horizontal", "vertical", "top", "bottom", "inside", "outside", "up", "down", "front", "back", "left", "right", "clockwise", "counterclockwise", "high", "low", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, so they cannot be understood as limiting the specific scope of protection of the present invention.

[0023] See also Figures 1 to 4 , an in-situ hydrogen charging test device for assisting axial strain provided by the present invention is now described. An in-situ hydrogen charging test device for assisting axial strain, comprising an in-situ hydrogen charging box and a test adjustment mechanism. The in-situ hydrogen charging box is provided with a hollow chamber inside, and a sample 1 is longitudinally penetrated through the in-situ hydrogen charging box. The sample 1 is sealed with the top and bottom of the in-situ hydrogen charging box through sealing components respectively. The in-situ hydrogen charging box has a height deformation with the axial strain of the sample 1. A displacement sensor 4 for detecting the height displacement of the in-situ hydrogen charging box is provided on the outside of the in-situ hydrogen charging box. A platinum electrode 5 is provided on the top of the in-situ hydrogen charging box, and the lower end of the platinum electrode 5 penetrates into the hollow chamber. An acidic reaction solution 6 is filled in the in-situ hydrogen charging box, and the platinum electrode 5 is electrically connected to the sample 1 so that the acidic reaction solution 6 reacts to simulate the in-situ hydrogen charging environment in the hollow chamber; the test adjustment mechanism comprises a lifting component and a transverse movement component, and the transverse movement component comprises a screw transmission component 29 and a screw drive component 30 The in-situ hydrogen filling box is installed on the screw transmission member 29 through the horizontal support frame 27, and the screw driving member 30 drives the screw transmission member 29 to drive the lateral displacement of the in-situ hydrogen filling box; the lifting assembly includes two hydraulic support frames and a hydraulic driving member. The two hydraulic support frames are longitudinally arranged and spaced from each other. The upper end of the hydraulic support frame is provided with a lifting driving end. The two ends of the screw transmission member 29 are respectively rotatably arranged at the two lifting driving ends. The screw driving member 30 is arranged at any lifting driving end. The hydraulic driving member is arranged on the outside of any hydraulic support frame. An electromagnetic switch 31 for controlling the hydraulic distribution is arranged between the hydraulic driving member and the two hydraulic support frames. The hydraulic driving member drives the two lifting driving ends to rise and fall synchronously to drive the longitudinal displacement of the in-situ hydrogen filling box.

[0024] The present invention provides an in-situ hydrogen charging test device for assisting axial strain. Compared with the prior art, the sample 1 is enclosed in the in-situ hydrogen charging box, the electromagnetic switch 31 is turned on, and the hydraulic drive is used to drive the two lifting drive ends to synchronously lift and lower to drive the in-situ hydrogen charging box to move longitudinally. Then, the electromagnetic switch 31 is closed, and the lead screw drive 30 is used to drive the lead screw transmission 29 to drive the in-situ hydrogen charging box to move laterally, so that the in-situ hydrogen charging box moves to a predetermined stretching position to adapt to various axial strain test devices. By electrically connecting the sample 1 and the platinum electrode 5, the platinum electrode 5 is used as the anode, and the sample 1 is used as the cathode, and the acidic reaction solution 6 reacts in the hollow chamber to simulate the in-situ hydrogen charging environment, so that the sample 1 performs an axial strain test of the sample 1 under the in-situ hydrogen charging environment. At the same time, when the sample 1 performs the axial strain test, the displacement sensor 4 is used to monitor the axial displacement of the sample 1 in real time. In the in-situ hydrogen charging test device for assisting axial strain provided by the present invention, a device that realizes in-situ hydrogen charging of the sample 1 and can adapt to various axial strain tests at the same time can reflect the mechanical properties of the material under a real environment.

[0025] See also Figure 1 The in-situ hydrogen charging box includes a telescopic box body 2 and a box cover 3. The middle part of the outer peripheral wall of the telescopic box body 2 has an axial folding structure, the top of the telescopic box body 2 has an open end, the top of the outer wall of the telescopic box body 2 is provided with a mounting plate 7 extending outward, the displacement sensor 4 is arranged on the mounting plate 7, the lower end of the sample 1 passes through the bottom of the telescopic box body 2, and the horizontal support frame 27 is clamped on the bottom circumference of the in-situ hydrogen charging box; the box cover 3 is sealed and installed at the open end of the telescopic box body 2, the platinum sheet electrode 5 longitudinally passes through the box cover 3 and extends to the inside of the telescopic box body 2, and the upper end of the sample 1 passes through the box cover 3.

[0026] The telescopic box 2 and the box cover 3 are split structures, which can facilitate the installation of the sample 1. At the same time, the sealing material between the box cover 3 and the telescopic box 2 is made of rubber or silicone that is pressure-resistant and chemically inert, ensuring that during the hydrogen filling process, even if the internal pressure rises and the temperature fluctuates slightly, there will be no hydrogen leakage. By stretching the folding structure of the telescopic box 2, the internal space of the box can be quickly expanded, and the larger sample 1 can be easily accommodated, which provides the possibility for the smooth development of the experiment. On the contrary, if it is a test of small precision materials, the contraction folding structure can make the box fit closely to the sample 1, reduce unnecessary space waste, and ensure the efficiency of the hydrogen filling process. In addition, due to the existence of the folding structure, when the sample 1 is subjected to an axial strain test, the telescopic box 2 can also change with the change of the axial length of the sample 1, so that the axial deformation of the sample 1 can be quickly and intuitively detected.

[0027] For samples 1 of different widths, movable clamps can be set on the bottom of the telescopic box 2 and the box cover 3 respectively. The two movable clamps are respectively installed on both sides of the sample 1 and then clamped on the bottom of the telescopic box 2 and the box cover 3 at the same time, and the connection is sealed.

[0028] Preferably, a level 32 is provided on the horizontal support frame 27, and the level 32 can detect the levelness of the in-situ hydrogen charging box. In addition, a counterweight 33 is provided on the outer side of a lifting drive end where the lead screw drive 30 is not provided. If the levelness of the in-situ hydrogen charging box does not meet the requirements, the counterweight 33 can be adjusted to make the level 32 reach a level, thereby ensuring the horizontal state of the in-situ hydrogen charging box, and used in conjunction with the mechanical properties testing instrument, so that the sample 1 meets the requirements and is clamped in the fixture of the testing instrument.

[0029] See also Figure 1 and Figure 3 A drain valve 8 is provided at the bottom of the telescopic box 2, and a plurality of vents 9 are arranged side by side on the top of the box cover 3, and sodium bicarbonate particles are provided in the vents 9. During the sample 1 process, the drain valve 8 is in a closed state, which can prevent the acidic reaction solution 6 from leaking out of the hollow chamber. When the acidic reaction solution 6 needs to be discharged after the test is completed, it can be discharged by opening the drain valve 8, which is easy to operate. The vent 9 provides a channel for gas exchange inside and outside the box, ensuring the smooth flow of gas during the hydrogen filling process. Sodium bicarbonate particles are provided in the vent 9. During the hydrogen filling experiment, a small amount of acidic gas impurities will be mixed in. Once the acidic gas is discharged from the box, it will cause acid corrosion to the supporting experimental equipment and affect the experimental accuracy. As a mild alkaline neutralizer, the sodium bicarbonate particles are like a safety filter arranged in the vent 9. When the acid gas is discharged from the box through the vent 9, the sodium bicarbonate particles will quickly react with it and neutralize the acid gas into harmless salts and carbon dioxide gas, thereby effectively protecting external experimental equipment and operators.

[0030] See also Figures 1 to 3 The sealing assembly includes an inner sealing sleeve 10, two sub-clamps 11 and an outer sealing sleeve 13. The inner sealing sleeve 10 is sleeved on the outer periphery of the root of the gauge length deformation section of the specimen 1; the two sub-clamps 11 are arranged horizontally opposite to each other, and the opposite ends of the sub-clamps 11 are provided with longitudinally bent clamping plates 12, the two clamping plates 12 are clamped on both sides of the inner sealing sleeve 10 respectively, and the sub-clamps 11 are connected to the upper end surface of the in-situ hydrogen charging box or the lower end surface of the in-situ hydrogen charging box; the outer sealing sleeve 13 is sleeved on the outer periphery of the two clamping plates 12.

[0031] Among them, the inner sealing sleeve 10 is the first barrier in direct contact with the sample 1. It is tightly sleeved on the outer periphery of the root of the gauge deformation section of the sample 1. During the hydrogen filling process of the sample 1, the gauge deformation section is often the area with the most concentrated stress and the most sensitive changes, and the root of the gauge deformation section is the bonding area between the sample 1 and the in-situ hydrogen filling box. The inner sealing sleeve 10 can effectively prevent hydrogen from leaking from the bonding area, ensuring the constant hydrogen concentration during the experiment and the accuracy of the test results. The opposite ends of the sub-chuck 11 are provided with longitudinally bent clamping plates 12. This bending structure greatly enhances the stability and sealing of the clamping. When the two clamping plates 12 are clamped on both sides of the inner sealing sleeve 10, a secondary tightening of the inner sealing sleeve 10 is formed. Among them, the two ends of the clamping plate 12 are locked by bolts to squeeze the inner sealing sleeve 10 located between the two clamping plates 12 to further improve its sealing effect. After the two clamping plates 12 clamp the inner sealing sleeve 10, bolts are used to penetrate the sub-clamps 11 from top to bottom and screwed into the upper or lower end surface of the in-situ hydrogen charging box. This connection method allows the sealing component to adapt to different experimental layouts and sample 1 installation requirements. Finally, the outer sealing sleeve 13 is sleeved on the outer periphery of the two clamping plates 12, which adds a layer of protective cover to the internal structure that has been initially sealed, further strengthening the sealing effect. In summary, the inner sealing sleeve 10, the two sub-clamps 11 and the outer sealing sleeve 13 cooperate with each other to form a sealing assembly that fully guarantees the sealing of the in-situ hydrogen charging box and provides stable and reliable experimental conditions for scientific research on materials in a hydrogen environment.

[0032] See also Figure 4 A first hydraulic cylinder 14 is provided at the lower part of the hydraulic support frame, and a first hydraulic chamber 15 filled with hydraulic oil is provided in the first hydraulic cylinder 14, and a first piston 16 is provided at the top sliding seal of the first hydraulic chamber 15, and a hydraulic rod 28 is vertically provided on the upper end surface of the first piston 16, and a lifting drive end is correspondingly provided at the upper end of the hydraulic rod 28; the hydraulic drive component includes a second hydraulic cylinder 17, and a second hydraulic chamber 18 filled with hydraulic oil is provided in the second hydraulic cylinder 17, and a second piston 19 is provided at the top sliding seal of the second hydraulic chamber 18, and a driving assembly is provided at the bottom of the second hydraulic chamber 18, and the two first hydraulic chambers 15 and the second hydraulic chamber 18 are connected through a connecting pipe 20, and the driving assembly drives the second piston 19 to rise and fall, so that the hydraulic oil in the second hydraulic chamber 18 enters or leaves the two first hydraulic chambers 15, which is used to drive the two first pistons 16 to drive the first hydraulic rod 28 to rise and fall. Among them, the second hydraulic cylinder 17 is also connected to the adjacent first hydraulic cylinder 14 through a connecting pipe 20. The above-mentioned electromagnetic switch 31 is arranged on the connecting pipe 20. It can control the pressure of the hydraulic oil between the first hydraulic chamber 15 and the second hydraulic chamber 18, thereby controlling the lifting and lowering of the two hydraulic rods 28, and finally achieving the purpose of adjusting the height of the in-situ hydrogen filling box.

[0033] The lower part of the hydraulic support frame, where the first hydraulic cylinder 14 is arranged, is the power foundation of the entire support structure. The first hydraulic cylinder 14 is filled with a first hydraulic chamber 15 of hydraulic oil. At the top of the first hydraulic chamber 15, the first piston 16 provided with a sliding seal plays a transmission role. When the first piston 16 slides up and down in the first hydraulic chamber 15, the hydraulic rod 28 vertically arranged on its upper end surface converts the linear motion of the piston into an external supporting force. The lifting drive end is arranged at the upper end of the hydraulic rod 28, which is directly connected to the components that need to be supported and driven, and becomes a key node for force transmission. Whether it is an in-situ hydrogen filling box carrying a heavy specimen 1, or other auxiliary devices that need to dynamically adjust their positions during the experiment, the lifting drive end can rely on the stable force transmitted by the hydraulic rod 28 to accurately realize the lifting action and meet various dynamic requirements in the experimental process.

[0034] The second hydraulic chamber 18 filled with hydraulic oil in the second hydraulic cylinder 17 is connected to the first hydraulic chamber 15 through the connecting pipe 20 to construct a coordinated hydraulic passage. At the bottom of the second hydraulic chamber 18, a driving assembly is arranged to control the flow direction and flow rate of the hydraulic oil. The driving assembly drives the second piston 19 to rise and fall. When the second piston 19 is pressed down, the hydraulic oil in the second hydraulic chamber 18 flows into the two first hydraulic chambers 15 along the connecting pipe 20 under the action of pressure, so that the two first pistons 16 drive the first hydraulic rod 28 to rise synchronously, thereby raising the hydraulic support frame and the in-situ hydrogen charging box it supports; conversely, when the second piston 19 rises, the hydraulic oil flows back, and the first hydraulic rod 28 descends to achieve height adjustment. In summary, the hydraulic support frame and its related hydraulic drive components cooperate with each other, and with its stable and efficient hydraulic power transmission, it provides solid mechanical support and flexible controllability for the application of in-situ hydrogen charging boxes in complex experimental scenarios.

[0035] See also Figure 4 The driving assembly includes a traction roller 21, a traction motor 23 and a reset member. The traction roller 21 is located at the bottom of the second hydraulic chamber 18, and a traction rope 22 is wound around the traction roller 21, and the traction rope 22 is connected to the second piston 19; the traction motor 23 is arranged on the outside of the second hydraulic cylinder 17, and the driving end of the traction motor 23 is connected to the traction roller 21 through a coupling transmission, which is used to drive the traction roller 21 to rotate; the reset member is arranged in the second hydraulic chamber 18 and is located between the second piston 19 and the traction roller 21, which is used to drive the second piston 19 moved to the lower part of the second hydraulic chamber 18 to move upward and reset.

[0036] The traction roller 21 is located at the bottom of the second hydraulic chamber 18, and the traction rope 22 on it is directly connected to the second piston 19. This connection method can efficiently convert the rotational motion of the traction roller 21 into a linear pull on the second piston 19, ensuring the accuracy and stability of power transmission. The traction motor 23 is arranged on the outside of the second hydraulic cylinder 17, and its driving end is connected to the traction roller 21 through a coupling transmission. When the experimental scene needs to adjust the height of the in-situ hydrogen filling box, the traction motor 23 starts quickly after receiving the command. The traction motor 23 can rotate with a very small speed error according to the preset program, drive the traction roller 21 to rotate smoothly through the coupling, and then pull the traction rope 22, accurately drive the second piston 19 to move downward in the second hydraulic chamber 18, and realize the precise control of the flow direction and flow of the hydraulic oil, providing ideal conditions for the experiment.

[0037] The reset component is arranged in the second hydraulic chamber 18 and is located between the second piston 19 and the traction roller 21. When the traction motor 23 drives the second piston 19 to move downward and completes the task of raising the hydraulic support frame and the in-situ hydrogen charging box, the reset component begins to play a role. The reset component uses its own elastic potential energy or other reset mechanisms to drive the second piston 19 that has moved to the lower part of the second hydraulic chamber 18 to move upward and reset. This process not only ensures that the system can quickly return to the initial state and prepare for the next driving operation, but also prevents the second piston 19 from being in a low position for a long time due to factors such as gravity in some emergencies, such as power outages or motor failures, thereby avoiding damage to the hydraulic system and ensuring the safety and stability of the entire in-situ hydrogen charging box experimental device.

[0038] See also Figure 1 The reset member includes a limiting edge 24 and a spring 25. The limiting edge 24 is integrally formed in the circumference of the middle and lower part of the second hydraulic chamber 18 and is located above the traction roller 21; the lower end of the spring 25 is arranged in the circumference of the limiting edge 24, and the spring 25 is located below the second piston 19. The second piston 19 moving to the lower part of the second hydraulic chamber 18 compresses the spring 25, and the spring 25 provides elastic force to drive the second piston 19 to move upward and reset.

[0039] The limiting edge 24 defines the boundary for the downward movement of the spring 25 and the second piston 19. When the second piston 19 moves downward under the drive of the traction motor 23, the limiting edge 24 can effectively prevent it from moving downward excessively, avoiding accidents such as collision with the traction roller 21, and ensuring the safety of the system. When the experimental operation causes the second piston 19 to move to the lower part of the second hydraulic chamber 18, the second piston 19 will compress the spring 25. At this time, the spring 25 stores elastic potential energy. When the in-situ hydrogen charging box needs to move upward, the traction motor 23 drives the traction roller 21 to rotate in the opposite direction, and the traction rope 22 is continuously released from the traction roller 21. The spring 25 releases the elastic potential energy to gradually lift the second piston 19 to move upward. At the same time, the traction rope 22 is still in the state of pulling the second piston 19, so that the second piston 19 can slowly rise.

[0040] By using the above-mentioned reset component, when the traction motor 23 stops working or there is an emergency such as a power outage or motor failure, the spring 25 will use its stored elastic potential energy to release elastic force, drive the second piston 19 to move upward and reset. For example, during a long-term high-strength material hydrogen charging experiment, a power outage suddenly occurred. At this time, if there is no reset effect of the spring 25, the second piston 19 may be in a low position for a long time due to gravity, resulting in uneven distribution of hydraulic oil, and may even damage the sealing structure of the hydraulic system. However, thanks to the existence of the spring 25, it quickly pushes the second piston 19 to reset upward, ensuring the integrity of the hydraulic system, so that the experimental device can be quickly restarted after power is restored and continue to operate normally.

[0041] See also Figure 4 The traverse assembly includes a lead screw transmission member 29 and a lead screw driving member 30. The lead screw transmission member 29 is composed of a lead screw and a matching nut. The lead screw is usually made of high-strength alloy steel with excellent wear resistance and rigidity, and its surface is finely threaded to ensure smooth and accurate transmission. The nut is made of self-lubricating materials such as copper alloy, which tightly bites the lead screw to reduce friction loss and ensure transmission efficiency.

[0042] The lead screw drive 30 is a servo motor, which has high-precision control performance and can accurately output torque to drive the lead screw to rotate. The output shaft of the motor is firmly connected to one end of the lead screw through a coupling. The coupling uses an elastic coupling, which can effectively transmit torque and buffer the impact generated when the motor starts and stops, protecting the lead screw and the motor.

[0043] The horizontal support frame 27 is made of aluminum alloy, and has a lightweight design while ensuring sufficient structural strength. A slider is designed at the bottom, and the slider cooperates with the guide rail. The guide rail is fixedly installed on the base of the equipment along the direction in which the in-situ hydrogen charging box needs to move horizontally, providing stable support for the in-situ hydrogen charging box and guiding its linear movement. The support frame and the in-situ hydrogen charging box are connected by bolts, and rubber shock-absorbing pads are used at the connection to prevent the slight vibration generated by the hydrogen charging box during operation from being transmitted to the screw drive system, affecting its accuracy and service life. The two horizontal support frames 27 are distributed on the left and right and jointly supported on the bottom of the in-situ hydrogen charging box. The two horizontal support frames 27 can keep the sample 1 in a vertical state at all times and maintain the centering requirements of the sample 1, which greatly reduces the error of the experiment and prevents the influence of human errors on the experimental results during the clamping process.

[0044] Preferably, at least one lifting drive end of the hydraulic support frame is provided with a hydrogen concentration sensor 26, and the hydrogen concentration sensor 26 is electrically connected to an alarm through a controller. The hydrogen concentration sensor 26 monitors the subtle changes in the surrounding hydrogen concentration at all times. Because during the hydrogen filling experiment, even a very small amount of hydrogen leakage may cause serious consequences, which will not only affect the accuracy of the experimental data, but also may cause explosions when hydrogen and air are mixed to a certain proportion and encounter open flames, endangering the safety of personnel and equipment. The hydrogen concentration sensor 26 captures hydrogen concentration information in real time with its high-precision detection capability and quickly transmits the data to the controller. After receiving the signal from the hydrogen concentration sensor 26, the controller immediately performs a quick and accurate analysis and judgment. Once the hydrogen concentration exceeds the preset safety threshold, the controller decisively issues an instruction to trigger the alarm electrically connected to it. The alarm then emits a loud and rapid alarm sound to promptly inform the experimenter of the arrival of potential danger. The hydrogen concentration sensor 26, the controller and the alarm work together, and cooperate with other components such as the hydraulic drive assembly of the in-situ hydrogen filling box to provide a full range of guarantees for the normal operation of the sample 1 device.

[0045] Based on the same inventive concept, please refer to Figure 5 The present invention also provides an in-situ hydrogen charging test method for assisting axial strain, using the above-mentioned in-situ hydrogen charging test device for assisting axial strain, comprising the following steps: S1: Sample 1 was mechanically ground from #150 to #2000 using metallographic silicon carbide paper, cleaned in an ethanol solution and blown dry, and then installed in an in-situ hydrogen charging box.

[0046] During this process, the grinding pressure is controlled between 0.5-1.5N / cm², which can not only ensure the effective removal of surface defects, but also prevent damage to sample 1 due to excessive pressure. At the same time, each grinding time is about 3-5 minutes, which is appropriately adjusted according to the material and initial surface condition of sample 1 to ensure uniform grinding effect. The concentration of the selected ethanol solution is 95%-99%. This concentration range can ensure good solubility and fast volatility, which is conducive to the subsequent drying operation. When drying, clean hot air with a temperature of 40-50℃ is used, and the wind speed is controlled at 0.8-1.2m / s, which can not only quickly dry sample 1, but also avoid thermal shock or physical damage to sample 1 caused by high temperature and high-speed airflow.

[0047] S2: Use the lifting assembly and the lateral movement assembly in the test adjustment mechanism to move the in-situ hydrogen charging box to a predetermined position, and wrap the portion of the sample 1 located outside the in-situ hydrogen charging box with silica gel.

[0048] Turn on the electromagnetic switch 31, and the lifting component starts to move. The lifting speed of the lifting component can be adjusted between 0.5-2cm / s to meet the needs of different experimental rhythms. The lifting component moves into place, and then the electromagnetic switch 31 is turned off; the lateral movement accuracy of the lateral movement component reaches ±0.05mm, ensuring precise positioning in the horizontal direction.

[0049] The sealing property of silicone can effectively prevent these impurity gases from invading the in-situ hydrogen charging box, ensure the purity of the hydrogen charging environment, and avoid the introduction of impurities that interfere with the hydrogen charging effect. The selected silicone has a Shore hardness of 30-40HA and has good flexibility. It can fit tightly to both sample 1 and the joint between sample 1 and the in-situ hydrogen charging box. In addition, silicone forms an insulating layer on the exposed area of ​​sample 1, which prevents leakage in the exposed area of ​​sample 1 after the power supply is connected to the power supply. The thickness of the silicone package is controlled at 2-3mm, which can provide sufficient protection without affecting the heat exchange and other physical interactions between sample 1 and the external environment due to excessive thickness.

[0050] S3: Inject the acidic reaction solution 6 into the in-situ hydrogen charging box, connect the platinum electrode 5 and the sample 1 to a constant current power supply, use the platinum electrode 5 as the anode and the sample 1 as the cathode, and the acidic reaction solution 6 reacts in the hollow chamber to simulate the in-situ hydrogen charging environment, and at the same time, perform a tensile test on the sample 1.

[0051] The output current accuracy of the constant current power supply is controlled at ±0.001A to ensure the stability of the hydrogen charging process. The platinum electrode 5 acts as the anode, which can stably provide electrons during the power-on process, maintain the smooth flow of the circuit, and ensure the continuous migration of hydrogen ions; the sample 1 acts as the cathode, attracting hydrogen ions to gather on its surface. The tensile test is carried out while hydrogen is charged, which highly restores the stress state of the material in actual application. The loading rate of the tensile test is set to 0.1-0.3mm / min, and it is appropriately adjusted according to the material properties of sample 1 and the research purpose. It can not only ensure the effectiveness of the test, but also avoid premature fracture of sample 1 or inaccurate data due to excessive loading.

[0052] S4: The in-situ hydrogen charging box deforms in the height direction along with the axial strain of the sample 1. The displacement sensor 4 detects the deformation amount of the in-situ hydrogen charging box in the height direction to obtain the axial strain amount of the sample 1 in the in-situ hydrogen charging environment.

[0053] In step S3, when the acidic reaction solution 6 is injected into the in-situ hydrogen charging box, the acidic reaction solution 6 is a 0.5 mol / L H2SO4 solution, and 1 g / L thiourea is added at the same time. As a typical strong acid electrolyte, the 0.5 mol / L H2SO4 solution is the key player in providing hydrogen ions. When the constant current power supply is turned on, the hydrogen ions in the solution migrate toward the surface of the sample 1 in an orderly manner under the drive of the electric field, thereby simulating a strong acidic hydrogen charging environment rich in hydrogen ions. By constructing a hydrogen charging environment in the in-situ hydrogen charging box, researchers can predict the performance of the material under actual working conditions in advance, providing a key basis for the optimal design of the material.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An in-situ hydrogen charging test device for assisting axial strain, characterized in that: include: An in-situ hydrogen charging box, wherein the in-situ hydrogen charging box has a hollow chamber inside, a sample (1) is longitudinally penetrated by the in-situ hydrogen charging box, the sample (1) is respectively sealed with the top and bottom of the in-situ hydrogen charging box through a sealing assembly, the in-situ hydrogen charging box has a height deformation with the axial strain of the sample (1), a displacement sensor (4) for detecting the height displacement of the in-situ hydrogen charging box is arranged on the outside of the in-situ hydrogen charging box, a platinum electrode (5) is arranged on the top of the in-situ hydrogen charging box, the lower end of the platinum electrode (5) penetrates into the hollow chamber, an acidic reaction solution (6) is filled in the in-situ hydrogen charging box, and the platinum electrode (5) is electrically connected to the sample (1) so that the acidic reaction solution (6) reacts to simulate the in-situ hydrogen charging environment in the hollow chamber; A test adjustment mechanism, the test adjustment mechanism comprises a lifting assembly and a transverse movement assembly, the transverse movement assembly comprises a screw transmission member (29) and a screw drive member (30), the in-situ hydrogen filling box is installed on the screw transmission member (29) through a horizontal support frame (27), and the screw drive member (30) is used to drive the in-situ hydrogen filling box to move horizontally by driving the screw transmission member (29); the lifting assembly comprises two hydraulic support frames and a hydraulic drive member, the two hydraulic support frames are both longitudinally arranged and spaced from each other, the upper end of the hydraulic support frame is provided with a lifting drive end, the two ends of the screw transmission member (29) are respectively rotatably arranged on the two lifting drive ends, the screw drive member (30) is arranged on any of the lifting drive ends, the hydraulic drive member is arranged on the outside of any of the hydraulic support frames, an electromagnetic switch (31) for controlling hydraulic pressure distribution is arranged between the hydraulic drive member and the two hydraulic support frames, and the hydraulic drive member is used to drive the in-situ hydrogen filling box to move longitudinally by driving the two lifting drive ends to rise and fall synchronously.

2. An in-situ hydrogen charging test device for assisting axial strain as claimed in claim 1, characterized in that: The in-situ hydrogen charging box comprises: A telescopic box (2), wherein the middle portion of the outer peripheral wall of the telescopic box (2) has an axial folding structure, the top of the telescopic box (2) has an open end, the top of the outer wall of the telescopic box (2) is provided with a mounting plate (7) extending outward, the displacement sensor (4) is provided on the mounting plate (7), the lower end of the sample (1) passes through the bottom of the telescopic box (2), and the horizontal support frame (27) is clamped on the bottom circumference of the in-situ hydrogen charging box; A box cover (3), wherein the box cover (3) is sealed and mounted on the open end of the telescopic box (2), the platinum sheet electrode (5) longitudinally penetrates the box cover (3) and extends to the interior of the telescopic box (2), and the upper end of the sample (1) penetrates the box cover (3).

3. An in-situ hydrogen charging test device for assisting axial strain as claimed in claim 2, characterized in that: A drain valve (8) is provided at the bottom of the telescopic box (2), and a plurality of vent holes (9) are arranged side by side at the top of the box cover (3), wherein sodium bicarbonate particles are arranged in the vent holes (9).

4. The in-situ hydrogen charging test device for assisting axial strain according to claim 1, characterized in that: The sealing assembly comprises: An inner sealing sleeve (10), the inner sealing sleeve (10) being sleeved on the outer periphery of the root of the gauge length deformation section of the sample (1); Two sub-clamps (11), the two sub-clamps (11) are arranged horizontally opposite to each other, and longitudinally bent clamping plates (12) are arranged at opposite ends of the sub-clamps (11), the two clamping plates (12) are clamped on both sides of the inner sealing sleeve (10) respectively, and the sub-clamps (11) are connected to the upper end surface of the in-situ hydrogen charging box or the lower end surface of the in-situ hydrogen charging box; An outer sealing sleeve (13) is sleeved on the outer circumference of the two clamping plates (12).

5. The in-situ hydrogen charging test device for assisting axial strain according to claim 1, characterized in that: A first hydraulic cylinder (14) is arranged at the lower part of the hydraulic support frame, a first hydraulic chamber (15) filled with hydraulic oil is arranged in the first hydraulic cylinder (14), a first piston (16) is arranged at the top sliding seal of the first hydraulic chamber (15), a hydraulic rod (28) is arranged vertically on the upper end surface of the first piston (16), and the lifting drive end is arranged correspondingly at the upper end of the hydraulic rod (28); the hydraulic drive component comprises a second hydraulic cylinder (17), a second hydraulic chamber (18) filled with hydraulic oil is arranged in the second hydraulic cylinder (17), a second piston (19) is arranged at the top sliding seal of the second hydraulic chamber (18), a driving assembly is arranged at the bottom of the second hydraulic chamber (18), the two first hydraulic chambers (15) and the second hydraulic chamber (18) are connected through a connecting pipe (20), and the driving assembly drives the second piston (19) to rise and fall so that the hydraulic oil in the second hydraulic chamber (18) enters or leaves the two first hydraulic chambers (15), so as to drive the two first pistons (16) to drive the first hydraulic rod (28) to rise and fall.

6. An in-situ hydrogen charging test device for assisting axial strain as claimed in claim 5, characterized in that: The drive assembly comprises: A traction roller (21), the traction roller (21) being located at the bottom of the second hydraulic chamber (18), a traction rope (22) being wound around the traction roller (21), and the traction rope (22) being connected to the second piston (19); A traction motor (23), the traction motor (23) being arranged outside the second hydraulic cylinder (17), the driving end of the traction motor (23) being connected to the traction roller (21) via a coupling, and being used for driving the traction roller (21) to rotate; A reset member is arranged in the second hydraulic chamber (18) and between the second piston (19) and the traction roller (21), and is used for driving the second piston (19) moved to the lower part of the second hydraulic chamber (18) to move upward and reset.

7. An in-situ hydrogen charging test device for assisting axial strain as claimed in claim 6, characterized in that: The reset member comprises: A limiting edge (24), the limiting edge (24) being integrally formed in the circumference of the middle and lower part of the second hydraulic chamber (18) and being located above the traction roller (21); A spring (25), wherein the lower end of the spring (25) is arranged in the circumferential direction of the limiting edge (24), and the spring (25) is located below the second piston (19). The second piston (19) moves to the lower part of the second hydraulic chamber (18) to compress the spring (25), and the spring (25) provides an elastic force to drive the second piston (19) to move upward and reset.

8. The in-situ hydrogen charging test device for assisting axial strain as claimed in claim 1, characterized in that: A hydrogen concentration sensor (26) is provided at the lifting drive end of at least one of the hydraulic support frames, and the hydrogen concentration sensor (26) is electrically connected to an alarm via a controller.

9. An in-situ hydrogen charging test method for assisting axial strain, characterized in that: The in-situ hydrogen charging test device for assisting axial strain as claimed in any one of claims 1 to 8 is used, comprising the following steps: S1: Sample (1) was mechanically ground from #150 to #2000 using metallographic silicon carbide paper, cleaned in an ethanol solution and blown dry, and the sample (1) was installed in an in-situ hydrogen charging box; S2: using the lifting assembly and the lateral movement assembly in the test adjustment mechanism to move the in-situ hydrogen charging box to a predetermined position, and wrapping the portion of the sample (1) located outside the in-situ hydrogen charging box with silica gel; S3: injecting an acidic reaction solution (6) into the in-situ hydrogen charging box, connecting the platinum electrode (5) and the sample (1) to a constant current power supply, with the platinum electrode (5) as the anode and the sample (1) as the cathode, the acidic reaction solution (6) reacts in the hollow chamber to simulate the in-situ hydrogen charging environment, and at the same time, performing a tensile test on the sample (1); S4: The in-situ hydrogen charging box deforms in the height direction along with the axial strain of the sample (1). The displacement sensor (4) detects the deformation amount of the in-situ hydrogen charging box in the height direction, thereby obtaining the axial strain amount of the sample (1) in the in-situ hydrogen charging environment.

10. An in-situ hydrogen charging test method for assisting axial strain according to claim 9, characterized in that: In step S3, when the acidic reaction solution (6) is injected into the in-situ hydrogen charging box, the acidic reaction solution (6) is a 0.5 mol / L H2SO4 solution, and 1 g / L thiourea is added at the same time.

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