Device and method for testing hydrogen compatibility of material

Abstract

The invention belongs to the technical field of hydrogen energy safety engineering, and particularly relates to a material hydrogen compatibility testing device and method. The material hydrogen compatibility testing device comprises a high-pressure kettle; the stretching rod penetrates through the high-pressure kettle in a sliding sealing manner, and the two ends of the stretching rod are located on the inner side and the outer side of the high-pressure kettle respectively; the two ends of a columnar sample are connected with the autoclave and the stretching rod through the clamps respectively, and the central axis of the sample coincides with the central axis of the stretching rod. The problem that in the prior art, the requirement for the machining precision of a disc sample is harsh can be solved, and the problem that in the prior art, the disc sample possibly deforms or generates uneven internal stress in the clamping process can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of hydrogen energy safety engineering, and in particular, relates to a material hydrogen compatibility testing device and a material hydrogen compatibility testing method. Background Art

[0002] As a new energy source, hydrogen has been favored in recent years because of its green and environmental protection. At the same time, the development of hydrogen energy has also led to an increasing demand for hydrogen. The increase in hydrogen demand has led to an increase in hydrogen storage and transportation.

[0003] In the process of hydrogen storage and transportation, high-pressure compression is generally used. In recent years, due to the continuous increase in the pressure of high-pressure hydrogen systems and the more severe service environment, the hydrogen embrittlement problem of materials used in high-pressure hydrogen systems has become particularly prominent.

[0004] Hydrogen embrittlement will increase the brittleness of the material, causing cracks after failure, which are prone to crack propagation, leading to sudden failure of the high-pressure hydrogen system during service and leakage of hydrogen stored inside, causing significant casualties and property losses.

[0005] In order to ensure the service safety of high-pressure hydrogen systems, the materials used must undergo hydrogen compatibility tests to ensure safety.

[0006] Existing metal material hydrogen compatibility testing devices and methods mainly include differential pressure high-pressure hydrogen and material compatibility testing devices and methods, which use disc-shaped sheets as samples and use the pressure difference between the upper and lower surfaces of the disc sample to apply a load to the disc sample.

[0007] The following problems exist in this test process: 1. The disc specimen is relatively thin and needs to maintain uniform thickness, so the processing accuracy of the specimen is relatively stringent; 2. The disc specimen needs to be clamped in an annular shape. During the clamping process, deformation or uneven internal stress may occur, which has a great impact on subsequent test results; 3. The displacement measurement device is placed in the test chamber and is easily damaged by the high-pressure hydrogen environment, resulting in inaccurate measurements. Summary of the invention

[0008] In response to the technical problems mentioned above, the present invention aims to propose a material hydrogen compatibility testing device, which uses a columnar specimen different from a disc specimen, and can solve the problem of stringent processing precision requirements for disc specimens in the prior art, as well as the problem that disc specimens in the prior art may deform or generate uneven internal stress during the clamping process.

[0009] The present invention also proposes a material hydrogen compatibility testing method, which adopts the material hydrogen compatibility testing device provided by the present invention, and can perform hydrogen compatibility testing on the material.

[0010] According to the present invention, a material hydrogen compatibility testing device is provided, comprising:

[0011] Autoclave;

[0012] A stretching rod is provided on the autoclave in a sliding seal, and two ends of the stretching rod are respectively located at the inner and outer sides of the autoclave;

[0013] A clamp, wherein two ends of the columnar sample are respectively connected to the autoclave and the stretching rod through the clamp, and the central axis of the sample coincides with the central axis of the stretching rod.

[0014] In a preferred embodiment, the autoclave comprises an autoclave body and an autoclave cover for sealing the autoclave body. Specifically, the autoclave body is configured as a cylinder with an upper end open, and the autoclave cover is coaxially sealed and disposed at the upper end of the autoclave body. A sealing gasket is disposed between the autoclave cover and the autoclave body, and a plurality of bolt holes are disposed on the autoclave cover along the circumferential direction for installing fastening bolts, and the plurality of fastening bolts fix and seal the autoclave cover at the upper end of the autoclave body.

[0015] In a preferred embodiment, the stretching rod is slidably and sealably penetrated on the kettle cover in the vertical direction. The lower end of the stretching rod is located below the kettle cover, that is, inside the kettle body. The upper end of the stretching rod is located above the kettle cover, that is, outside the kettle body.

[0016] The stretching rod and the kettle cover are sealed by a sealing member.

[0017] A fixture for fixing the sample is set in the autoclave, and a fixture is also set at the lower end of the stretching rod. In addition, the central axes of the two fixtures coincide, so as to avoid the problem of misalignment between the fixture and the sample during the stretching rod loading process, which causes the stretching rod to be subjected to a lateral load component. If the stretching rod is subjected to a lateral load component, on the one hand, it will cause the stretching rod to deform laterally, aggravate the wear between the stretching rod and the autoclave cover, and affect the sealing performance. On the other hand, it will affect the measurement accuracy of load and displacement, thereby reducing the accuracy of this material hydrogen compatibility experiment.

[0018] During the experiment, both ends of the columnar sample were connected to the stretching rod and the autoclave through clamps, and the central axis of the sample coincided with the central axis of the stretching rod.

[0019] In a preferred embodiment, the specimen can be made of the material to be tested into a round bar specimen or a dog-bone bar specimen used in conventional tensile and fatigue tests.

[0020] The chuck fixtures for round rod specimens or dog-bone rod specimens are relatively mature and will not affect the middle gauge length section during the clamping process. This can avoid the deformation or uneven internal stress that occurs when using disc specimens in the prior art, which has a significant impact on subsequent test results.

[0021] In addition, the processing accuracy required for making round rod specimens or dog-bone rod specimens is much lower than that of disc specimens. Using round rod specimens or dog-bone rod specimens can reduce the production cost of the specimens.

[0022] In a preferred embodiment, the clamp is arranged to be movable relative to the stretching rod, and a moving path of the clamp is perpendicular to and intersects with a central axis of the stretching rod.

[0023] Under this setting, even when the sample is connected to the autoclave and the stretching rod through the clamp, the sample and the stretching rod are not coaxial due to installation errors during the stretching of the sample by the stretching rod. The clamp can automatically respond to the tension of the stretching rod and adjust the position of the sample to minimize the coaxiality deviation between the stretching rod and the autoclave cover, thereby avoiding the stretching rod from being subjected to lateral load components, reducing the wear of the stretching rod, and improving the accuracy of the experiment.

[0024] In a preferred embodiment, the clamp is arranged to be rotatable relative to the stretching rod, and the rotation axis of the clamp is parallel to the rotation axis of the stretching rod.

[0025] In this setup, the grips are also able to respond to the tension of the tensile rod, eliminating the effects of torque on the specimen during loading.

[0026] In a preferred embodiment, the clamp is connected to the stretching rod or the autoclave via a calibration mechanism, and the calibration mechanism includes a rotating chassis, a slideway is arranged on the rotating chassis, and a slider is slidably arranged in the slideway.

[0027] The calibration mechanism may be arranged between the stretching rod and its corresponding clamp, or the calibration mechanism may be arranged between the autoclave and its corresponding clamp.

[0028] In a specific embodiment, when the calibration mechanism is disposed between the stretching rod and its corresponding clamp, the rotating chassis is connected to the clamp via a rotating shaft to form a rotating pair, so that the rotating chassis can rotate relative to the clamp. The slider is fixedly connected to the lower end of the stretching rod.

[0029] Alternatively, the rotating chassis is coaxially rotatably arranged at the lower end of the stretching rod via a rotating shaft, and the sliding block is fixedly connected to the clamp.

[0030] In a specific embodiment, when the calibration mechanism is disposed between the autoclave and its corresponding fixture, the rotating chassis is connected to the fixture via a rotating shaft to form a rotating pair, so that the rotating chassis can rotate relative to the fixture. The slider is fixedly connected to the lower end of the autoclave.

[0031] Alternatively, the rotating chassis is coaxially rotatably connected to the autoclave via a rotating shaft, and the slider is fixedly connected to the fixture.

[0032] In a preferred embodiment, the clamp is arranged to be rotatable relative to the stretching rod, and the rotation axis of the clamp coincides with the central axis of the stretching rod.

[0033] In a preferred embodiment, a load sensor is arranged on the stretching rod.

[0034] Furthermore, the load sensor is located on the portion of the stretching rod that is located outside the autoclave. In this way, the load sensor is arranged outside the autoclave to measure the load of the load and the load of the sample. On the one hand, it can avoid the high-pressure hydrogen environment in the autoclave from affecting the sensitivity and reliability of the load sensor, and prevent the load sensor from being damaged in the high-pressure hydrogen environment, thereby improving the service life of the load sensor and the accuracy of the experiment. On the other hand, if the load sensor is arranged inside the autoclave, it is also necessary to provide a hole on the autoclave for passing the load sensor wire, which will increase the difficulty of sealing and reduce the structural stability of the autoclave. The load sensor of the present invention is arranged outside the autoclave, which avoids the occurrence of the above-mentioned problems.

[0035] In a preferred embodiment, a displacement bracket is connected between the stretching rod and the autoclave, and a displacement sensor for measuring the tensile deformation of the sample is arranged on the displacement bracket.

[0036] In a preferred embodiment, the displacement bracket comprises a measuring section, the measuring section is parallel to the central axis of the stretching rod, and the displacement sensor is arranged on the measuring section.

[0037] Furthermore, the displacement bracket also includes a connecting section.

[0038] The connecting section is perpendicular to the stretching rod, one end of the connecting section is fixedly connected to the stretching rod, and the other end of the connecting section is fixedly connected to the measuring section.

[0039] The upper end of the measuring section is fixedly connected to the connecting section, and the lower end of the measuring section is fixedly connected to the autoclave. The displacement sensor is located between the upper and lower ends of the measuring section.

[0040] In a preferred embodiment, as shown in the figure, a plurality of displacement brackets are provided, and the plurality of displacement brackets are evenly arranged along the circumferential direction, and a displacement sensor is respectively provided on each displacement bracket. The plurality of displacement brackets can balance the force on the stretching rod, so that the force on the stretching rod is even, and prevent the stretching rod from tilting. At the same time, the displacement sensors installed on the plurality of displacement brackets can measure simultaneously, reducing the influence of errors in the measurement process.

[0041] In a preferred embodiment, it further comprises a stretching mechanism and a loading beam movably arranged on the stretching mechanism, and the autoclave and the stretching rod are connected to the stretching mechanism and the loading beam respectively.

[0042] Specifically, as shown in the figure, the stretching mechanism includes a bottom plate, a column and a top plate. The top plate is fixedly arranged above the bottom plate through the column.

[0043] The lower end of the autoclave is fixedly arranged on the upper end surface of the bottom plate. A loading beam is movably arranged on the stretching mechanism in the vertical direction, and the loading beam is fixedly connected to the stretching rod. The loading beam can drive the stretching rod to move upward, thereby applying an upward pulling force to the sample.

[0044] In a preferred embodiment, the material hydrogen compatibility testing device further comprises:

[0045] A gas supply mechanism is connected to the autoclave. A pipeline connected to the gas supply mechanism is arranged on the autoclave.

[0046] In a preferred embodiment, the gas supply mechanism comprises a hydrogen cylinder group and a nitrogen cylinder group, the hydrogen cylinder group is connected to the autoclave via a first pipe valve member, and the nitrogen cylinder group is connected to the autoclave via a second pipe valve member.

[0047] The hydrogen cylinder group can provide hydrogen to the autoclave, and the first pipe valve can achieve stable output of hydrogen in the hydrogen cylinder group or realize flow cutoff to prevent air or high-pressure gas in the downstream pipeline from being compressed into the hydrogen cylinder group.

[0048] The nitrogen cylinder group contains high-pressure nitrogen, which can purge the gas in the autoclave. A discharge pipeline for exhaust is provided on the autoclave. The second pipe valve can realize the stable output of nitrogen in the nitrogen cylinder group or realize the interception, preventing the air, high-pressure hydrogen in the hydrogen cylinder group or high-pressure gas in the downstream pipeline from being compressed to the nitrogen cylinder group.

[0049] In a preferred embodiment, a primary pressurizing mechanism and a secondary pressurizing mechanism are sequentially arranged between the gas supply mechanism and the autoclave.

[0050] The hydrogen enters the primary pressurizing mechanism and the secondary pressurizing mechanism through the hydrogen cylinder group and the first pipe valve member to be pressurized and then enters the autoclave.

[0051] In a preferred embodiment, it further comprises a temperature control module, and the temperature control module controls the temperature of the autoclave.

[0052] In this embodiment, the temperature control module exchanges heat for the autoclave through an oil bath to ensure that the ambient temperature inside the autoclave is stable and controllable, thereby providing the required ambient temperature for the tensile specimen.

[0053] According to the present invention, a material hydrogen compatibility testing method is also provided, using the material hydrogen compatibility testing device provided by the present invention, comprising the following steps:

[0054] The autoclave containing the sample was purged with nitrogen;

[0055] Use hydrogen to replace the nitrogen in the autoclave. After the replacement is completed, increase the hydrogen pressure in the autoclave according to the experimental requirements;

[0056] Control the temperature of the autoclave according to the experimental requirements;

[0057] The sample is stretched, and the load and displacement are recorded to obtain the stress-strain curve.

[0058] In the actual measurement process, the test sample is placed in the autoclave and fastened with a clamp. The length between the two clamps is measured as the gauge length, and the load sensor and displacement sensor are fixedly connected. After the autoclave is replaced with nitrogen three times, the nitrogen in the autoclave is replaced with hydrogen. After the replacement is completed, the hydrogen required for the experiment is filled to maintain the pressure, and the temperature control module is turned on to control the temperature of the hydrogen environment in the autoclave. The sample is stretched, the load size and displacement size are recorded, and the final stress-strain curve is obtained.

[0059] Compared with the prior art, the advantages of the present application are as follows.

[0060] The present invention adopts a columnar specimen, and the axial ends of the columnar specimen are fixedly connected to a clamp and a stretching rod respectively. Under this setting, on the one hand, the processing accuracy requirements of the columnar specimen are low, which is convenient for production; on the other hand, the columnar specimen will not be deformed or produce uneven internal stress due to the fixed connection of the clamp or the stretching rod, thereby improving the accuracy of the experiment.

[0061] In addition, the clamp of the present invention is movably arranged in the autoclave. During the tensile test, the clamp can automatically calibrate the position in response to the tension of the stretching rod, so that the central axis of the clamp and the stretching rod coincide, which can effectively solve the problem of different axes during the loading process of the stretching rod and avoid wear of the sliding connection between the stretching rod and the autoclave. Through this arrangement, on the one hand, the accuracy of the experiment can be improved; on the other hand, the service life of the stretching rod can be extended.

[0062] The displacement sensor and load sensor of the present invention are both arranged outside the autoclave, thereby avoiding the influence of the hydrogen environment in the autoclave on the displacement sensor and the load sensor, ensuring the sensitivity and reliability of the displacement sensor and the load sensor, and further improving the accuracy of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] The present invention will be described below with reference to the accompanying drawings.

[0064] Figure 1 A schematic diagram showing an embodiment of an autoclave and its auxiliary structures of a material hydrogen compatibility testing device according to the present invention;

[0065] Figure 2 A schematic diagram showing an embodiment of a calibration mechanism according to the present invention;

[0066] Figure 3 A schematic diagram showing an embodiment of a rotating chassis according to the present invention is shown;

[0067] Figure 4 A schematic diagram showing an embodiment of a slider according to the present invention;

[0068] Figure 5 A schematic top view of a first embodiment of a displacement bracket according to the present invention is shown;

[0069] Figure 6 A schematic top view of a second embodiment of a displacement bracket according to the present invention is shown;

[0070] Figure 7 A schematic diagram showing an embodiment of a material hydrogen compatibility testing device according to the present invention is shown.

[0071] In the figure: 1, autoclave; 10, discharge pipeline; 11, autoclave body; 12, autoclave cover; 13, fastening bolts;

[0072] 2. stretching rod; 21. load sensor;

[0073] 3. Fixture;

[0074] 4. calibration mechanism; 41. slideway; 42. slider; 43. rotating chassis; 44. rotating shaft;

[0075] 5. displacement bracket; 51. displacement sensor; 52. measuring section; 53. connecting section;

[0076] 61, stretching mechanism; 611, bottom plate; 612, column; 613, top plate; 62, loading beam;

[0077] 7. Gas supply mechanism; 71. Hydrogen cylinder group; 72. Nitrogen cylinder group; 73. First pipe valve member; 74. Second pipe valve member;

[0078] 81. First-stage booster mechanism; 82. Second-stage booster mechanism;

[0079] 9. Temperature control module;

[0080] 100. Material hydrogen compatibility testing device.

[0081] In the present application, all drawings are schematic drawings, which are only used to illustrate the principles of the present invention and are not drawn according to the actual scale. DETAILED DESCRIPTION

[0082] The present invention will be described below with reference to the accompanying drawings.

[0083] It should be noted that the directional terms or qualifiers "upper", "lower", "left", "right", etc. used in this application are all with reference to the drawings to which they are referred. They are not used to limit the absolute positions of the components involved, but can be changed according to specific circumstances.

[0084] Figure 1 A schematic diagram showing an autoclave 1 and its accessory structures of a material hydrogen compatibility testing device 100 according to the present invention.

[0085] like Figure 1 As shown, the material hydrogen compatibility testing device 100 comprises an autoclave 1 .

[0086] The autoclave 1 comprises a kettle body 11 and a kettle cover 12 for sealing the kettle body 11. Specifically, in the present embodiment, the kettle body 11 is configured as a cylinder with an open upper end, and the kettle cover 12 is coaxially and sealingly disposed at the upper end of the kettle body 11. Preferably, a sealing gasket (not shown in the figure) is disposed between the kettle cover 12 and the kettle body 11, and a plurality of bolt holes are disposed on the kettle cover 12 along the circumferential direction for installing fastening bolts 13, and the plurality of fastening bolts 13 fix and seal the kettle cover 12 at the upper end of the kettle body 11.

[0087] A stretching rod 2 is provided in a sliding and sealing manner on the autoclave 1 , and two ends of the stretching rod 2 are located at the inner and outer sides of the autoclave 1 respectively.

[0088] Specifically, in this embodiment, the stretching rod 2 is slidably and sealably penetrated on the kettle cover 12 in the vertical direction. The lower end of the stretching rod 2 is located below the kettle cover 12, that is, inside the kettle body 11. The upper end of the stretching rod 2 is located above the kettle cover 12, that is, outside the kettle body 11.

[0089] The stretching rod 2 and the kettle cover 12 are sealed by a seal (not shown in the figure). The specific sealing mechanism between the stretching rod 2 and the kettle cover 12 is not a technical point of the present invention and will not be described in detail here.

[0090] A clamp 3 for fixing the sample is provided in the autoclave 1, and a clamp 3 is also provided at the lower end of the stretching rod 2, and the central axes of the two clamps 3 coincide, so as to avoid the problem of the stretching rod 2 being subjected to a lateral load component due to the misalignment of the clamp 3 and the sample (not shown in the figure) during the loading process of the stretching rod 2. If the stretching rod 2 is subjected to a lateral load component, on the one hand, the stretching rod 2 will be deformed laterally, aggravating the wear between the stretching rod 2 and the autoclave cover 12 and affecting the sealing performance. On the other hand, it will affect the measurement accuracy of the load and displacement, thereby reducing the accuracy of this material hydrogen compatibility experiment.

[0091] During the experiment, both ends of the columnar sample are connected to the stretching rod 2 and the autoclave 1 through the clamps 3 , respectively, and the central axis of the sample coincides with the central axis of the stretching rod 2 .

[0092] In a preferred embodiment, the specimen can be made of the material to be tested into a round bar specimen or a dog-bone bar specimen used in conventional tensile and fatigue tests.

[0093] The chuck fixtures for round rod specimens or dog-bone rod specimens are relatively mature and will not affect the middle gauge length section during the clamping process. This can avoid the deformation or uneven internal stress that occurs when using disc specimens in the prior art, which has a significant impact on subsequent test results.

[0094] In addition, the processing accuracy required for making round rod specimens or dog-bone rod specimens is much lower than that of disc specimens. Using round rod specimens or dog-bone rod specimens can reduce the production cost of the specimens.

[0095] In a preferred embodiment, in order to further avoid the situation where the stretching rod 2 is not coaxial with the clamp 3 and the sample (not shown in the figure) during the loading process, causing the stretching rod 2 to be subjected to a lateral load component, the clamp 3 is configured to be able to move relative to the stretching rod 2, and the moving path of the clamp 3 is perpendicular to and intersects the central axis of the stretching rod 2.

[0096] Under this setting, even when the sample is connected to the autoclave 1 and the stretching rod 2 through the clamp 3, the sample and the stretching rod 2 are not coaxial during the stretching of the sample by the stretching rod 2 due to installation errors, the clamp 3 can automatically respond to the pulling force of the stretching rod 2 and adjust the position of the sample to minimize the coaxiality deviation between the stretching rod 2 and the autoclave cover 12, thereby avoiding the situation where the stretching rod 2 is subjected to lateral load components, reducing the wear of the stretching rod 2, and improving the accuracy of the experiment.

[0097] Further, on the basis that the clamp 3 can move relative to the stretching rod 2 , the clamp 3 is configured to be rotatable relative to the stretching rod 2 , and the rotation axis of the clamp 3 is parallel to the rotation axis of the stretching rod 2 .

[0098] In this setting, the clamp 3 can also respond to the tension of the stretch rod 2 and eliminate the influence of the torque on the specimen during the loading process.

[0099] In a preferred embodiment, when the clamp 3 cannot move relative to the stretching rod 2, if it is necessary to enable the clamp 3 to respond to the tension of the stretching rod 2 and eliminate the influence of the torque on the sample during the loading process, the clamp 3 can be set to be able to rotate relative to the stretching rod 2, and the rotation axis of the clamp 3 coincides with the central axis of the stretching rod 2.

[0100] According to the present invention, in a specific embodiment, the fixture 3 is calibrated by the calibration mechanism 4 (not in Figure 1 ) to move or rotate relative to the stretching rod 2. It is easy to understand that the calibration mechanism 4 can be arranged between the stretching rod 2 and its corresponding clamp 3, and the calibration mechanism 4 can also be arranged between the autoclave 1 and its corresponding clamp 3.

[0101] Furthermore, two calibration mechanisms 4 may be provided, and the two calibration mechanisms 4 are respectively provided between the stretching rod 2 and its corresponding clamp 3 , and between the autoclave 1 and its corresponding clamp 3 .

[0102] In a specific embodiment, Figure 2 to Figure 4 As shown, Figure 2 is a schematic diagram of the structure of the calibration mechanism 4 of the present invention, Figure 3 for Figure 2 Schematic diagram of the cross section in the nn direction, Figure 4 The calibration mechanism 4 includes a rotating chassis 43 , a slideway 41 and a slider 42 .

[0103] In this embodiment, the slideway 41 is a groove provided on one end surface of the rotating chassis 43, and the slider 42 is adapted to the slideway 41, that is, the slider 42 can move along the slideway 41. Further, the moving path of the slider 42 passes through the central axis of the rotating chassis 43.

[0104] A rotating shaft 44 is disposed on the other end surface of the rotating chassis 43 , and the central axis of the rotating shaft 44 coincides with the central axis of the rotating chassis 43 .

[0105] In a specific embodiment, when the calibration mechanism 4 is disposed between the stretching rod 2 and its corresponding clamp 3, the rotating chassis 43 is connected to the clamp 3 via the rotating shaft 44 to form a rotating pair, so that the rotating chassis 43 can rotate relative to the clamp 3. The slider 42 is fixedly connected to the lower end of the stretching rod 2.

[0106] Alternatively, the rotating chassis 43 is coaxially rotatably arranged at the lower end of the stretching rod 2 via the rotating shaft 44 , and the slider 42 is fixedly connected to the clamp 3 .

[0107] In a specific embodiment, when the calibration mechanism 4 is disposed between the autoclave 1 and the corresponding fixture 3, the rotating chassis 43 is connected to the fixture 3 via the rotating shaft 44 to form a rotating pair, so that the rotating chassis 43 can rotate relative to the fixture 3. The slider 42 is fixedly connected to the lower end of the autoclave 1.

[0108] Alternatively, the rotating chassis 43 is coaxially rotatably connected to the autoclave 1 via the rotating shaft 44 , and the slider 42 is fixedly connected to the fixture 3 .

[0109] like Figure 1 As shown, a load sensor 21 is provided on the stretching rod 2. Further, the load sensor 21 is located on the portion of the stretching rod 2 located outside the autoclave 1. In this way, the load sensor 21 is arranged outside the autoclave 1 to measure the load applied to the sample.

[0110] On the one hand, it can prevent the high-pressure hydrogen environment in the autoclave 1 from affecting the sensitivity and reliability of the load sensor 21 and prevent the load sensor 21 from being damaged in the high-pressure hydrogen environment, thereby improving the service life of the load sensor 21 and the accuracy of the experiment.

[0111] On the other hand, if the load sensor 21 is disposed inside the autoclave 1, a hole for passing the wire of the load sensor 21 needs to be provided on the autoclave 1, which increases the difficulty of sealing and reduces the structural stability of the autoclave 1. The load sensor 21 of the present invention is disposed outside the autoclave 1, thereby avoiding the above problems.

[0112] like Figure 1 and Figure 5 As shown, a displacement bracket 5 is connected between the stretching rod 2 and the autoclave 1 , and a displacement sensor 51 for measuring the tensile deformation of the sample is arranged on the displacement bracket 5 .

[0113] According to the present invention, the displacement bracket 5 comprises a measuring section 52 , the measuring section 52 is parallel to the central axis of the stretching rod 2 , and the displacement sensor 51 is arranged on the measuring section 52 .

[0114] Furthermore, the displacement bracket 5 also includes a connecting section 53 .

[0115] The connecting section 53 is perpendicular to the stretching rod 2 , one end of the connecting section 53 is fixedly connected to the stretching rod 2 , and the other end of the connecting section 53 is fixedly connected to the measuring section 52 .

[0116] The upper end of the measuring section 52 is fixedly connected to the connecting section 53, and the lower end of the measuring section 52 is fixedly connected to the autoclave 1. The displacement sensor 51 is located between the upper and lower ends of the measuring section 52.

[0117] In a preferred embodiment, Figure 6As shown, there are multiple displacement brackets 5, and the multiple displacement brackets 5 are evenly arranged along the circumferential direction, and a displacement sensor 51 is respectively arranged on each displacement bracket 5. The multiple displacement brackets 5 can balance the force on the stretching rod 2, make the stretching rod 2 evenly stressed, and prevent the stretching rod 2 from tilting.

[0118] In a specific embodiment, the material hydrogen compatibility testing device 100 further includes a stretching mechanism 61 and a loading beam 62 movably disposed on the stretching mechanism 61 , and the autoclave 1 and the stretching rod 2 are connected to the stretching mechanism 61 and the loading beam 62 , respectively.

[0119] Specifically, Figure 1 As shown, the stretching mechanism 61 includes a bottom plate 611, a column 612 and a top plate 613. The top plate 613 is fixedly arranged above the bottom plate 611 through the column 612.

[0120] The lower end of the autoclave body 11 of the autoclave 1 is fixedly arranged on the upper end surface of the bottom plate 611. A loading beam 62 is movably arranged in the vertical direction on the stretching mechanism 61, and the loading beam 62 is fixedly connected to the stretching rod 2. The loading beam 62 can drive the stretching rod 2 to move upward, thereby applying an upward pulling force to the sample.

[0121] It is easy to understand that the specific structures of the stretching mechanism 61 and the loading beam 62 are all prior arts, which are not the technical points of the present invention and will not be described in detail here.

[0122] It should be noted that, although the present embodiment describes the structure of the stretching mechanism 61 and the loading beam 62 , the present invention is not limited to such a structure, as long as it can provide an upward pulling force for the stretching rod 2 relative to the autoclave 1 .

[0123] like Figure 7 As shown, in a specific embodiment, the material hydrogen compatibility testing device 100 further includes a gas supply mechanism 7 , which is connected to the autoclave 1 to provide gas to the autoclave 1 .

[0124] It is easy to understand that the autoclave 1 is provided with a pipeline (not shown in the figure) connected to the gas supply mechanism 7 .

[0125] In a specific embodiment, the gas supply mechanism 7 includes a hydrogen cylinder group 71 , and the hydrogen cylinder group 71 is connected to the autoclave 1 via a first pipe valve member 73 .

[0126] The hydrogen cylinder group 71 can provide hydrogen to the autoclave 1 , and the first pipe valve member 73 can achieve stable output of hydrogen in the hydrogen cylinder group 71 or realize flow cutoff to prevent air or high-pressure gas in the downstream pipeline from being compressed into the hydrogen cylinder group 71 .

[0127] In a preferred embodiment, the gas supply mechanism 7 further includes a nitrogen bottle group 72 , and the nitrogen bottle group 72 is connected to the autoclave 1 via a second pipe valve member 74 .

[0128] The nitrogen cylinder group 72 contains high-pressure nitrogen, which can purge the gas in the autoclave 1. A discharge pipeline 10 for exhaust is provided on the autoclave 1. The second pipe valve 74 can realize the stable output of nitrogen in the nitrogen cylinder group 72 or realize the interception, so as to prevent the air, the high-pressure hydrogen in the hydrogen cylinder group 71 or the high-pressure gas in the downstream pipeline from being compressed to the nitrogen cylinder group 72.

[0129] When the hydrogen cylinder group 71 is provided, the first pipe valve member 73 can prevent the high-pressure nitrogen in the nitrogen cylinder group 72 from being compressed into the hydrogen cylinder group 71 .

[0130] In a preferred embodiment, a primary pressurizing mechanism 81 and a secondary pressurizing mechanism 82 are sequentially arranged between the gas supply mechanism 7 and the autoclave 1 .

[0131] The hydrogen enters the primary pressurizing mechanism 81 and the secondary pressurizing mechanism 82 through the hydrogen cylinder assembly 71 and the first pipe valve member 73 to be pressurized and then enters the autoclave 1 .

[0132] In a preferred embodiment, the material hydrogen compatibility testing device 100 further includes a temperature control module 9 , which controls the temperature of the autoclave 1 .

[0133] In this embodiment, the temperature control module 9 performs heat exchange on the autoclave 1 by oil bathing, so as to ensure that the internal ambient temperature of the autoclave 1 is stable and controllable, thereby providing the required ambient temperature for the tensile specimen.

[0134] According to the present invention, a method for testing hydrogen compatibility of a material is also provided, comprising the following steps:

[0135] The autoclave containing the sample was purged with nitrogen;

[0136] Use hydrogen to replace the nitrogen in the autoclave. After the replacement is completed, increase the hydrogen pressure in the autoclave according to the experimental requirements;

[0137] Control the temperature of the autoclave according to the experimental requirements;

[0138] The sample is stretched, and the load and displacement are recorded to obtain the stress-strain curve.

[0139] In view of the problems that sample processing is difficult and measuring devices are easily damaged in high-pressure hydrogen environments during material performance testing in high-pressure hydrogen environments, the purpose of the present invention is to provide a material hydrogen compatibility testing device 100, thereby providing testing technology and equipment support for the selection of high-pressure hydrogen materials.

[0140] The material hydrogen compatibility testing device 100 includes a displacement purge module, a tensile testing machine module, a high-pressure hydrogen environment reactor module, a pressurization and temperature change module and a displacement measurement module.

[0141] The high-pressure hydrogen environment reactor module comprises a high-pressure reactor 1, a reactor body 11, a reactor cover 12, fastening bolts 13 and corresponding sealing components.

[0142] The displacement purge module mainly provides nitrogen for displacement purge and hydrogen for experiment for the material hydrogen compatibility test device 100. The displacement purge module, namely the gas supply mechanism 7, mainly includes a hydrogen cylinder group 71, a nitrogen cylinder group 72, a first pipe valve member 73, and a second pipe valve member 74.

[0143] The hydrogen cylinder group 71 mainly provides a hydrogen source for the autoclave 1 and realizes the replacement and purging of hydrogen in the pipeline of the entire device.

[0144] The nitrogen cylinder group 72 mainly provides a gas source for the air replacement in the pipeline of the entire device and the autoclave 1. The first pipe valve 73 can realize the stable output or cutoff of the hydrogen in the hydrogen cylinder group 71, and prevent the high-pressure nitrogen in the air, the nitrogen cylinder group 72, or the high-pressure gas in the downstream pipeline from being compressed to the hydrogen cylinder group 71. The second pipe valve 74 can realize the stable output or cutoff of the nitrogen in the nitrogen cylinder group 72, and prevent the high-pressure hydrogen in the air, the hydrogen cylinder group 71, or the high-pressure gas in the downstream pipeline from being compressed to the nitrogen cylinder group 72.

[0145] The tensile testing machine module mainly includes a tensile mechanism 61, a bottom plate 611, a column 612, a top plate 613 and a loading beam 62, as well as corresponding tensile rods 2, load sensors 21, clamps 3, etc., which can provide the required load for sample stretching.

[0146] The function of the stretching rod 2 is to connect the loading crossbeam 62 and the material sample in the autoclave 1 to provide a load transfer function. At the same time, since part of the stretching rod 2 needs to extend into the autoclave 1 and contact with high-pressure hydrogen, ordinary carbon steel materials or stainless steel materials may suffer from hydrogen embrittlement damage during long-term experiments, affecting the accuracy of the test, and severe fatigue fractures may occur, affecting the safety of the test. During the experiment, the stretching rod 2 needs to contact the autoclave cover 12 of the autoclave 1 and produce relative sliding. Ordinary carbon steel materials or stainless steel materials may suffer from wear during long-term experiments, which leads to poor sealing and hydrogen leakage. In this embodiment, the stretching rod 2 is made of 316L stainless steel material with high strength, high wear resistance and hydrogen embrittlement resistance, which can effectively avoid the above problems. At the same time, the stretching rod 2 adopts a transverse slidable connection, which can effectively solve the problem of different axes during the loading process of the stretching rod 2 and avoid wear of the stretching rod 2 under transverse force.

[0147] The main function of the load sensor 21 is to measure the load size during the tensile test. In order to ensure the sensitivity and reliability of the load sensor 21 and to prevent the problem of reduced structural strength caused by perforation of the autoclave 1, the load sensor 21 is connected to the stretching rod 2 and placed outside the autoclave 1, using an external measurement method to provide a tool for load measurement during the tensile process of the sample.

[0148] The main function of the clamp 3 is to provide clamping force for the sample during the stretching process to ensure that the sample does not fall off. In order to reduce the impact of the high-pressure hydrogen and high-temperature environment on the clamping force of the clamp 3, the clamp 3 is made of high-strength, high-wear-resistant, and hydrogen-embrittlement-resistant 316L stainless steel.

[0149] High-pressure hydrogen environment autoclave module, namely autoclave 1, such as Figure 2 As shown, it mainly includes a discharge pipeline 10, a kettle body 11, a kettle cover 12, and fastening bolts 13. The high-pressure hydrogen environment kettle module mainly provides a simulated high-pressure hydrogen high and low temperature environment for tensile tests, and truly characterizes the mechanical behavior of materials in a typical hydrogen environment.

[0150] In order to reduce the influence of the high-pressure hydrogen and high-temperature environment on the strength of the autoclave 1, the autoclave 1 is made of high-strength, high-wear-resistant, and hydrogen-embrittlement-resistant 316L stainless steel material.

[0151] The autoclave 1 is fixed on the stretching mechanism 61, and the bottom is connected to the stretching mechanism 61. The internal space of the autoclave 1 is used for sample connection. The bottom of the internal space is equipped with a clamp 3, and the clamp 3 is connected to the bottom of the autoclave 1 through a calibration mechanism 4. Figure 3 As shown, the calibration mechanism 4 can adjust the coaxiality of the tensile specimen in real time during the experiment to avoid problems such as inaccurate measurement data and equipment damage caused by excessive coaxiality deviation.

[0152] The calibration mechanism 4 includes a slide 41, a slider 42, a rotating chassis 43 and a rotating shaft 44. The slide 41 adopts a trapezoidal cross-section, which is conducive to the engagement and fixation with the slider 42. The lower end of the rotating chassis 43 is connected to the autoclave 1 through the rotating shaft 44, which can eliminate the influence of torque on the sample during the loading process.

[0153] The boosting and temperature-changing module includes a primary boosting mechanism 81, a secondary boosting mechanism 82, a temperature control module 9 and accessories, which can control the pressure and temperature in the autoclave 1. In order to improve the boosting efficiency and the upper limit of the boosting, the boosting and temperature-changing module adopts a multi-stage compression mechanism for boosting. Hydrogen enters the primary boosting mechanism 81 and the secondary boosting mechanism 82 through the hydrogen cylinder group 71 and the first pipe valve 73 for boosting and then enters the autoclave 1.

[0154] The displacement measurement module includes a displacement sensor 51, a displacement bracket 5 and a corresponding data processing system (not shown in the figure). The displacement measurement adopts an external measurement method. The displacement bracket 5 is fixed on the stretching rod 2. A single or multiple displacement brackets 5 are evenly distributed around the circumference of the stretching rod 2. Figure 4 Assume that the number of displacement brackets 5 is n, then the angle θ between the two brackets is designed as follows:

[0155]

[0156] During the measurement process, assuming that the values ​​of the displacement sensors 51 on the displacement brackets 5 are u1, u2, u3, ...un, respectively, the actual measurement value u is taken as the average value, that is,

[0157]

[0158] In the actual measurement process, the test sample is placed in the autoclave 1 and fastened with the clamp 3, the length between the two clamps 3 is measured as the gauge length, and the load sensor 21 and the displacement sensor 51 are fixedly connected. After the autoclave 1 is replaced with nitrogen three times, the nitrogen in the autoclave 1 is replaced with hydrogen. After the replacement is completed, the hydrogen required for the experiment is filled to maintain the pressure, the temperature control module 9 is turned on to control the temperature of the hydrogen environment in the autoclave 1, the sample is stretched, the load size and the displacement size are recorded, and the final stress-strain curve is obtained.

[0159] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0160] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0161] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0162] Finally, it should be noted that the above is only a preferred embodiment of the present invention and does not constitute any limitation to the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments or to replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A material hydrogen compatibility testing device, characterized in that: include: Autoclave (1); A stretching rod (2) is slidingly sealed and passed through the autoclave (1), with two ends of the stretching rod (2) being located at the inner and outer sides of the autoclave (1) respectively; A clamp (3), wherein both ends of the columnar sample are respectively connected to the autoclave (1) and the stretching rod (2) through the clamp (3), and the central axis of the sample coincides with the central axis of the stretching rod (2).

2. The material hydrogen compatibility testing device according to claim 1, characterized in that: The clamp (3) is arranged to be movable relative to the stretching rod (2), and the moving path of the clamp (3) is perpendicular to and intersects with the central axis of the stretching rod (2).

3. The material hydrogen compatibility testing device according to claim 2, characterized in that: The clamp (3) is arranged to be rotatable relative to the stretching rod (2), and the rotation axis of the clamp (3) is parallel to the rotation axis of the stretching rod (2).

4. The material hydrogen compatibility testing device according to claim 3, characterized in that: The clamp (3) is connected to the stretching rod (2) or the autoclave (1) via a calibration mechanism (4), wherein the calibration mechanism (4) comprises a rotating chassis (43), a slideway (41) is arranged on the rotating chassis (43), and a slider (42) is slidably arranged in the slideway (41).

5. The material hydrogen compatibility testing device according to claim 1, characterized in that: The clamp (3) is arranged to be rotatable relative to the stretching rod (2), and the rotation axis of the clamp (3) coincides with the central axis of the stretching rod (2).

6. The material hydrogen compatibility testing device according to claim 1, characterized in that: A load sensor (21) is arranged on the stretching rod (2).

7. The material hydrogen compatibility testing device according to claim 1, characterized in that: A displacement bracket (5) is connected between the stretching rod (2) and the autoclave (1), and a displacement sensor (51) for measuring the tensile deformation of the sample is arranged on the displacement bracket (5).

8. The material hydrogen compatibility testing device according to claim 7, characterized in that: The displacement bracket (5) comprises a measuring section (52), the measuring section (52) is parallel to the central axis of the stretching rod (2), and the displacement sensor (51) is arranged on the measuring section (52).

9. The material hydrogen compatibility testing device according to any one of claims 1 to 8, characterized in that: It also comprises a stretching mechanism (61) and a loading beam (62) movably arranged on the stretching mechanism (61), and the autoclave (20) and the stretching rod (20) are respectively connected to the stretching mechanism (61) and the loading beam (62).

10. The material hydrogen compatibility testing device according to any one of claims 1 to 8, characterized in that: Also includes: A gas supply mechanism (7), wherein the gas supply mechanism (7) is connected to the autoclave (1).

11. The material hydrogen compatibility testing device according to claim 10, characterized in that: The gas supply mechanism (7) comprises a hydrogen bottle group (71) and a nitrogen bottle group (72); the hydrogen bottle group (71) is connected to the autoclave (1) via a first pipe valve member (73); and the nitrogen bottle group (72) is connected to the autoclave (1) via a second pipe valve member (74).

12. The material hydrogen compatibility testing device according to claim 10, characterized in that: A primary pressure boosting mechanism (81) and a secondary pressure boosting mechanism (82) are arranged in sequence between the gas supply mechanism (7) and the autoclave (1).

13. The material hydrogen compatibility testing device according to claim 10, characterized in that: It also comprises a temperature control module (9), and the temperature control module (9) controls the temperature of the autoclave (1).

14. A method for testing hydrogen compatibility of materials, characterized in that: Using the material hydrogen compatibility testing device according to any one of claims 1 to 13 comprises the following steps: The autoclave containing the sample was purged with nitrogen; Use hydrogen to replace the nitrogen in the autoclave. After the replacement is completed, increase the hydrogen pressure in the autoclave according to the experimental requirements; Control the temperature of the autoclave according to the experimental requirements; The sample is stretched, and the load and displacement are recorded to obtain the stress-strain curve.

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