A hydrogen embrittlement test method and device for slow strain tensile test evaluation

Abstract

The present invention relates to the technical field of metal hydrogen embrittlement evaluation test, in particular to a hydrogen embrittlement test method and device for slow strain tensile test evaluation, comprising a test bench, a traction component and a servo motor, wherein the traction component is fixedly installed above the test bench, the traction component comprises a screw, a slide rail, a slider and a fixed plate installed on the slider, the servo motor is fixedly installed above the traction component, and the output shaft of the servo motor is fixedly connected to the end of the screw in the traction component through a coupling, and a traction disc is symmetrically installed at the middle of the fixed plate in the traction component and the upper part of the test bench, the present invention utilizes a detachable and replaceable traction disc as a fixed component for tensile test detection materials, and provides a mutually independent and stable clamping method for a variety of test materials, thereby avoiding the limitations of the current traditional tensile test platform on material selection and improving applicable scenarios and uses.

Description

Technical Field

[0001] The invention relates to the technical field of metal hydrogen embrittlement evaluation test, in particular to a hydrogen embrittlement test method and device for slow strain tensile test evaluation. Background Art

[0002] During the solidification process of metal, hydrogen embrittlement occurs when the hydrogen dissolved in the metal cannot be released in time and diffuses to the vicinity of defects in the metal. At room temperature, atomic hydrogen combines into molecular hydrogen at the defects and continues to aggregate, thereby generating huge internal pressure and causing the metal to crack. Once hydrogen embrittlement occurs, it will not only affect the mechanical properties of the material, but also have a serious impact on the safety and reliability of the equipment.

[0003] High-strength metal materials are more susceptible to hydrogen embrittlement, such as structural steel, aluminum alloys, and nickel alloys. Aluminum alloy is a widely used material, especially in the fields of construction, aviation, automobiles, and shipbuilding. Stress corrosion and hydrogen embrittlement of aluminum alloys have caused certain restrictions on their application. In aluminum alloys, hydrogen can enter the material from the external environment and concentrate in some local areas, causing the brittleness of these areas to increase significantly;

[0004] Therefore, non-destructive testing of metal materials should be carried out regularly, such as using acoustic emission testing, ultrasonic testing, X-ray testing and other methods to evaluate the health of materials, and conducting slow strain tensile tests on aluminum alloy materials in conjunction with hydrogen embrittlement testing. The actual tensile properties and compressive load values ​​of aluminum alloy materials after hydrogen embrittlement can be accurately determined, and data and theoretical and practical support can be provided for subsequent production, processing or maintenance and inspection. However, aluminum alloy products come in a variety of forms, and the currently commonly used tensile test platforms can only provide a single clamp method, which is difficult to meet the strength testing needs of various materials after hydrogen embrittlement. Summary of the invention

[0005] In order to address the deficiencies of the prior art, the present invention provides a hydrogen embrittlement testing device for slow strain tensile test evaluation, thereby solving the problem that the currently commonly used tensile test platforms can only provide a single clamp mode and are difficult to meet the needs of post-hydrogen embrittlement strength detection tests for various materials.

[0006] The technical solution adopted by the present invention to solve its technical problem is a hydrogen embrittlement test device for slow strain tensile test evaluation, which includes a test bench, a traction assembly and a servo motor. The traction assembly is fixedly installed above the test bench. The traction assembly includes a screw, a slide rail, a slider and a fixed plate installed on the slider. The servo motor is fixedly installed above the traction assembly, and the output shaft of the servo motor is fixedly connected to the end of the screw in the traction assembly through a coupling. The traction disc is symmetrically installed in the middle of the fixed plate in the traction assembly and the upper part of the test bench.

[0007] The traction disk includes an inner disk and an outer disk. The inner disk is fixedly installed, and the outer disk is installed on the inner disk by means of rotational cooperation. A group of positioning seats are installed around the disk surface of the inner disk, and positioning pieces are installed on the positioning seats by means of rotational cooperation. The outer disk is provided with a positioning notch that engages with the positioning piece.

[0008] Preferably, the outer disk is fixedly mounted with a first clamping assembly, a second clamping assembly, a third clamping assembly and a fourth clamping assembly, and the first clamping assembly, the second clamping assembly, the third clamping assembly and the fourth clamping assembly are circumferentially distributed on the outer disk.

[0009] Preferably, the first clamping assembly and the second clamping assembly are arranged opposite to each other, and the main structures in the first clamping assembly and the second clamping assembly are composed of two elastic plates with the same structure, the first elastic plate is fixedly mounted on the outer disk, and the second elastic plate is fixedly mounted on the first elastic plate by means of tension bolts, and the inner plate surface of the elastic plate in the first clamping assembly is provided with wavy teeth for clamping sheet materials, and the elastic plate in the second clamping assembly is provided with an elastic disk for clamping filamentary materials by means of rotational cooperation.

[0010] Preferably, the elastic discs are all semi-circular disc structures, and the two elastic discs are respectively installed on the first and second elastic plates by rotational cooperation, and the facing surfaces of the two elastic plates are symmetrically provided with filamentary grooves adapted to the filamentary material.

[0011] Preferably, the filamentary grooves are provided in a plurality of groups in the circumferential direction, each group of filamentary grooves is provided with a plurality of grooves, and the inner groove surface of each groove is a rough structure.

[0012] Preferably, the third clamping assembly and the fourth clamping assembly are arranged opposite to each other, and the main structures in the third clamping assembly and the fourth clamping assembly include a clamping clamp, a clamping plate, a clamping cylinder, a clamping claw and an airbag. The clamping clamp is fixedly installed on the outer plate, and the clamping plate is fixedly installed on the clamping clamp. The central axis of the clamping plate is perpendicular to the central axis of the outer plate, one end of the clamping cylinder is installed on the clamping plate by means of rotational cooperation, the clamping claw is movably installed in the clamping cylinder, and the airbag is circumferentially installed in the middle position of the clamping cylinder.

[0013] Preferably, a flat pull rod is fixedly mounted on the clamping plate, the flat pull rod is circumferentially arranged, and a rubber ring made of elastic material is installed between the plurality of flat pull rods, the claws and the flat pull rods are arranged at intervals, and the rubber ring slides through the middle of the claws.

[0014] Preferably, the claw is an incomplete cylindrical structure, the center axis of the claw coincides with the center axis of the abutting tube, and the inner arc surface of the claw is provided with spiral grooves in a spiral manner for increasing the contact surface pressure.

[0015] Preferably, the bottom of the inner arc surface of the clamping cylinder and the outer arc surface of the clamping plate are provided with mutually meshing thread lines, a slip ring is fixedly installed on the outer arc surface of the claw, a step surface with a gradually changing thickness is fixedly installed in the middle of the inner arc surface of the clamping cylinder, and the slip ring is in sliding contact with the step surface, and the slip ring squeezes the airbag during sliding.

[0016] Preferably, the difference between the third clamping assembly and the fourth clamping assembly is that the third clamping assembly is used to clamp columnar or rod-shaped materials, and the fourth clamping assembly is used to clamp tubular materials.

[0017] A hook is movably mounted on the abutting cylinder of the third clamping assembly, the end of which is tilted to point to the axis of the abutting cylinder, a lever is hingedly mounted on one side of the hook, the middle of the lever passes through the abutting cylinder, and the other end of the lever rests on the side wall of the airbag;

[0018] A conical cylinder is fixedly installed on the clamping plate of the fourth clamping assembly. The conical ends of the conical cylinder are independent of each other. An expansion ball is fixedly installed on the bottom of the conical cylinder. The expansion ball fills the inner cavity of the conical cylinder, and the expansion ball is connected to the airbag. The outer contour of the conical cylinder is provided with a spiral groove with the same structure as the outer arc surface of the claw.

[0019] In addition, the present invention also provides a test method of a hydrogen embrittlement test device for slow strain tensile test evaluation, comprising the following steps:

[0020] S1. Material selection: First, select appropriate sheet, wire, rod or tubular materials for hydrogen embrittlement test. The material of the selected material is one of structural steel, aluminum alloy or nickel alloy. When the selected material is contaminated by hydrogen during the manufacturing process, or is exposed to a hydrogen-rich gas environment during use, hydrogen embrittlement will occur. This phenomenon will greatly reduce the strength and toughness of the material, and even cause the material to break. The hydrogen embrittlement test simulates the actual production or use conditions of the material, which can provide data and theoretical and practical support for the structural strength of the material and subsequent maintenance and improvement;

[0021] S2. Clamping and positioning: After the material is selected, the outer disk is rotated according to the shape of the material so that the clamping assembly corresponding to the material is in the working position. After the adjustment is completed, the outer disk and the inner disk are locked by the positioning piece. Then, the material is placed in the clamping assembly and the position is locked;

[0022] S3, tensile test: start the servo motor to run, so that it drives the screw in the traction assembly to rotate, and then drives the upper traction disk to move upward through the fixed plate, and the traction disk at the bottom remains fixed on the test bench;

[0023] S4. Data acquisition: Various data during the traction and stretching process are recorded through multiple sensors, and the tensile strength of the material is calculated by a computer to obtain the slow strain stretching test data.

[0024] Beneficial effects of the present invention:

[0025] (1) In the present invention, a detachable and replaceable traction disk is used as a fixing component for tensile test detection materials, and a clamping method that is independent of each other and has stability is provided for a variety of test materials, thereby avoiding the limitations of the current traditional tensile test platform on material selection and improving the applicable scenarios and uses.

[0026] (2) In the present invention, the relative rotation between the inner disk and the outer disk can realize the rapid switching of the clamp type and the clamping position. The locking action of multiple positioning plates can improve the linear alignment between two symmetrically installed clamps, so that multiple clamps can be quickly aligned and centered after the position conversion, thereby improving the verticality of the subsequent material after clamping, so that the material is evenly stressed during the subsequent stretching process, thereby improving the accuracy of the tensile test data.

[0027] (3) In the present invention, by quickly switching between a variety of clamps, an adaptive and stable clamping effect for sheet, filament, rod and tubular materials can be achieved, thereby increasing the amount of experimental samples and thereby increasing the universality and accuracy of the data. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0029] Figure 1 It is a schematic diagram of the overall connection structure of the present invention;

[0030] Figure 2 for Figure 1 A schematic diagram of the main view;

[0031] Figure 3 It is a schematic diagram of the installation positions of multiple clamping components in the present invention;

[0032] Figure 4 for Figure 3 A is an enlarged schematic diagram;

[0033] Figure 5 It is a schematic diagram of the installation relationship between the tension disc and the tension plate in the present invention;

[0034] Figure 6 for Figure 5 The enlarged schematic diagram of point B in FIG.

[0035] Figure 7 is a partial cross-sectional schematic diagram of the third clamping assembly in the present invention;

[0036] Figure 8 for Figure 7 The enlarged schematic diagram of point C in FIG.

[0037] Fig. 9 for Figure 7 The enlarged schematic diagram of D in FIG.

[0038] Fig.10 is a partial cross-sectional schematic diagram of the fourth clamping assembly in the present invention;

[0039] Fig.11 for Fig.10 The enlarged schematic diagram of point E in FIG.

[0040] In the figure:

[0041] 1. Test bench; 2. Traction assembly; 3. Servo motor; 4. Traction disc; 41. Inner disc; 42. Outer disc; 43. Positioning seat; 44. Positioning plate; 5. First clamping assembly; 6. Second clamping assembly; 7. Third clamping assembly; 8. Fourth clamping assembly; 51. Elastic plate; 52. Elastic bolt; 53. Tooth pattern; 54. Elastic disc; 55. Thread-like groove; 71. Tightening clamp; 72. Tightening disc; 73. Tightening cylinder; 74. Claw; 75. Airbag; 76. Flat pull rod; 77. Rubber ring; 78. Spiral groove; 79. Slip ring; 731. Step surface; 732. Hook claw; 733. Push rod; 721. Conical cylinder; 722. Expansion ball; a. Sheet-like; b. Thread-like; c. Rod-like; d. Tubular. DETAILED DESCRIPTION

[0042] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0043] The embodiment of the present invention provides a hydrogen embrittlement testing device for slow strain tensile test evaluation, thereby solving the problem that the currently commonly used tensile test platforms can only provide a single clamp mode and are difficult to meet the requirements of post-hydrogen embrittlement strength detection tests for various materials.

[0044] like Figure 1 and Figure 2 As shown, in order to save laboratory space and make the tensile test platform have a one-machine-multi-function effect, a preferred embodiment of the present invention proposes a hydrogen embrittlement test device for slow strain tensile test evaluation, including a test bench 1, a traction component 2 and a servo motor 3, wherein the traction component 2 is fixedly installed above the test bench 1, and the traction component 2 includes a screw, a slide rail, a slider and a fixed plate installed on the slider, the servo motor 3 is fixedly installed above the traction component 2, and the output shaft of the servo motor 3 is fixedly connected to the end of the screw in the traction component 2 through a coupling, and a traction disc 4 is symmetrically installed in the middle of the fixed plate in the traction component 2 and the upper part of the test bench 1.

[0045] In the present invention, a detachable and replaceable traction disk 4 is used as a fixed component for tensile test detection materials, and a mutually independent and stable clamping method is provided for various test materials, thereby avoiding the limitations of the current traditional tensile test platform on material selection and improving the applicable scenarios and uses.

[0046] Furthermore, in order to adapt to the selection of fixtures and the rapid switching effect during tensile tests of various materials, such as Figure 2 and Figure 3 As shown, the traction disk 4 includes an inner disk 41 and an outer disk 42. The inner disk 41 is fixedly installed, and the outer disk 42 is installed on the inner disk 41 by rotational cooperation. A group of positioning seats 43 are installed around the disk surface of the inner disk 41, and positioning pieces 44 are installed on the positioning seats 43 by rotational cooperation. The outer disk 42 is provided with a positioning notch engaged with the positioning piece 44. The first clamping assembly 5, the second clamping assembly 6, the third clamping assembly 7 and the fourth clamping assembly 8 are fixedly installed on the outer disk 42. The first clamping assembly 5, the second clamping assembly 6, the third clamping assembly 7 and the fourth clamping assembly 8 are distributed circumferentially on the outer disk 42.

[0047] During operation, the four groups of clamping components can call the required type of clamps according to the selected stretching materials. Compared with the single clamping method on the traditional stretching platform, the convenience of the sampling process of various types of tests is improved. In addition, through the relative rotation between the inner disk 41 and the outer disk 42, the type of clamps and the clamping orientation can be quickly switched. The snap-fitting action of the multiple positioning plates 44 can improve the linear alignment between the two symmetrically installed clamps, so that multiple clamps can be quickly aligned and centered after the orientation conversion, which improves the verticality of the subsequent material after clamping, so that the material is evenly stressed during the subsequent stretching process, thereby improving the accuracy of the stretching test data.

[0048] Furthermore, in order to achieve multi-functionality of one machine, the tensile test platform is expanded to be adaptable to the tensile strength of various hydrogen embrittled materials, such as Figures 3 to 6As shown, the first clamping assembly 5 and the second clamping assembly 6 are arranged opposite to each other. The main structures of the first clamping assembly 5 and the second clamping assembly 6 are composed of two elastic plates 51 with the same structure. The first elastic plate 51 is fixedly installed on the outer disk 42, and the second elastic plate 51 is fixedly installed on the first elastic plate 51 through a tightening bolt 52. The difference is that the inner plate surface of the elastic plate 51 in the first clamping assembly 5 is provided with a wavy tooth pattern 53 for clamping the sheet a material, and the second clamping assembly 5 is provided with a wavy tooth pattern 53 for clamping the sheet a material. The elastic plate 51 in part 6 is equipped with an elastic disc 54 for clamping the filamentary material b by means of rotational fit. The elastic discs 54 are all semi-circular disc structures. The two elastic discs 54 are respectively installed on the first and second elastic plates 51 by means of rotational fit, and the facing surfaces of the two elastic plates 51 are symmetrically provided with filamentary grooves 55 that are compatible with the filamentary material b. There are multiple groups of filamentary grooves 55 circumferentially arranged, and each group of filamentary grooves 55 is provided with multiple grooves, and the inner groove surface of each filamentary groove 55 is a rough structure.

[0049] During operation, when the stretched material is sheet a material, the outer disc 42 is rotated to make the first clamping assembly 5 on the traction assembly 2 at the bottom position, and the first clamping assembly 5 on the test bench 1 at the top position. After the rotation is completed, the position of the outer disc 42 is locked. At this time, the tension bolt 52 is turned to create a gap greater than the thickness of the sheet a material between the movable tension plate 51 and the fixed tension plate 51. Subsequently, the sheet a material is put in, the tension bolt 52 is reset and turned, and the sheet a material is clamped by the two tension plates 51. The wavy tooth pattern 53 provided on the clamping surface can increase the contact surface pressure with the sheet a material, thereby improving the clamping stability.

[0050] When the material to be stretched is filamentary material b, the position switching procedure is the same as that of the first clamping component 5. The second clamping components 6 at the upper and lower positions are placed in opposite working positions by rotating the outer disk 42. In the process of adjusting the distance between the two elastic plates 51 on the second clamping component 6, the relative positions of the two elastic disks 54 are adjusted synchronously. In addition, according to the diameter of the required clamped filamentary material b, the filamentary groove 55 with an appropriate notch diameter can be selected by rotating the elastic disk 54. The multiple groups of filamentary grooves 55 enrich the tensile test requirements of various filamentary material b that can be performed on the tensile test platform. In addition, each group of filamentary grooves 55 is provided with multiple channels. When conducting tensile tests on filamentary material b with the same diameter, multiple strands can be set at the same time to increase the experimental sample size and increase the universality and accuracy of the data.

[0051] Furthermore, in order to achieve multi-functionality of one machine, the tensile test platform is expanded to be adaptable to the tensile strength of various hydrogen embrittled materials, such as Figures 7 to 11As shown, the third clamping assembly 7 and the fourth clamping assembly 8 are arranged opposite to each other, and the main structures in the third clamping assembly 7 and the fourth clamping assembly 8 include a clamp 71, a clamp plate 72, a clamp cylinder 73, a claw 74 and an air bag 75. The clamp 71 is fixedly mounted on the outer disk 42, and the clamp plate 72 is fixedly mounted on the clamp 71. The central axis of the clamp plate 72 is perpendicular to the central axis of the outer disk 42, and one end of the clamp cylinder 73 is mounted on the clamp plate 72 by rotational cooperation. The claw 74 is movably mounted in the clamp cylinder 73, and the air bag 75 is circumferentially mounted in the middle position of the clamp cylinder 73. The difference between the third clamping assembly 7 and the fourth clamping assembly 8 is that the third clamping assembly 7 is used to clamp columnar or rod-shaped c materials, and the fourth clamping assembly 8 is used to clamp tubular d materials.

[0052] When working, the third clamping assembly 7 and the fourth clamping assembly 8 both clamp materials with a cylindrical outer contour. The third clamping assembly 7 is used to clamp solid columnar or rod-shaped c materials. When the tensile test platform processes hollow tubular d materials, the end of the tubular d material is subjected to continuous inward extrusion force during the tensile test. In order to ensure that the port diameter of the tubular d material can always maintain a standardized circularity, the fourth clamping assembly 8 is used for clamping. In the initial state, the multiple claws 74 are in an expanded and placed state. At this time, the material to be clamped is placed in the space formed by the multiple claws 74. Subsequently, in the process of the claws 74 contracting inwardly, a circumferential clamping effect on the material placed therein can be achieved, which improves the stability and makes the material self-centered, thereby ensuring the uniformity of force on various areas of the material during the subsequent tensile test.

[0053] Furthermore, in order to achieve the circumferential clamping effect on the rod-shaped c material or the tubular d material and improve its anti-slip ability during the tensile test, as Figures 7 to 11 As shown, a flat tie rod 76 is fixedly installed on the clamping plate 72, and the flat tie rod 76 is circumferentially arranged, and a rubber ring 77 of elastic material is installed between the plurality of flat tie rods 76. The claw 74 is arranged at intervals from the flat tie rod 76, and the rubber ring 77 slides through the middle of the claw 74. The claw 74 is an incomplete cylindrical structure, and the central axis of the claw 74 coincides with the central axis of the clamping tube 73. The inner arc surface of the claw 74 is provided with a spiral groove 78 for increasing the contact surface pressure in a spirally surrounding manner, and the bottom of the inner arc surface of the clamping tube 73 and the outer arc surface of the clamping plate 72 are provided with mutually meshing thread lines. A slip ring 79 is fixedly installed on the outer arc surface of the claw 74, and a step surface 731 with a gradually changing thickness is fixedly installed in the middle of the inner arc surface of the clamping tube 73, and the slip ring 79 is in sliding contact with the step surface 731, and the slip ring 79 squeezes the airbag 75 during sliding.

[0054] When the locking cam 73 is in the closed position, the locking cam 73 is in a closed position, and the locking cam 73 is in a closed position, so that ...

[0055] Furthermore, for the clamping of two different materials, solid and hollow, in order to ensure that the clamping force does not destroy the stability of the material itself and improve the clamping effect, such as Figures 7 to 11 A hook claw 732 is movably installed on the clamping cylinder 73 of the third clamping assembly 7 shown, and the end of the hook claw 732 is inclined to point to the axial position of the clamping cylinder 73. A lever 733 is hingedly installed on one side of the hook claw 732. The middle part of the lever 733 passes through the clamping cylinder 73, and the other end of the lever 733 rests on the side wall of the airbag 75.

[0056] When the third clamping assembly 7 is used to clamp the rod-shaped C material, along with the lateral movement caused by the rotation of the clamping tube 73, the airbag 75 is gradually squeezed by the sliding ring 79 and deformed. At this time, the deformed airbag 75 pushes the lever 733 to deflect, and then the tilted hook 732 is pushed in the direction close to the outer contour of the rod-shaped C material through the lever 733. When the hook 732 fits the outer contour of the rod-shaped C material, it provides a clamping force for it, and the friction force caused by mutual squeezing makes the rod-shaped C material rotate synchronously with the clamping tube 73. At this time, the claw 74 It is still approaching the outer contour of the rod-shaped C material. Through the rotation of the rod-shaped C material, when the outer contour of the rod-shaped C material comes into contact with the spiral groove 78, the spiral groove 78 gradually engages with the outer wall of the rod-shaped C material by screwing in, while improving the coaxiality of the rod-shaped C material and the clamping tube 73. Compared with the direct vertical fitting method, the screwing in of the spiral groove 78 can produce friction grooves of a certain depth at the outer contour position of the rod-shaped C material, further increasing the clamping stability of the rod-shaped C material and improving its anti-slip ability in subsequent tensile tests.

[0057] A conical cylinder 721 is fixedly installed on the clamping plate 72 of the fourth clamping assembly 8. The conical ends of the head of the conical cylinder 721 are independent of each other. An expansion ball 722 is fixedly installed on the bottom of the conical cylinder 721. The expansion ball 722 fills the inner cavity of the conical cylinder 721, and the expansion ball 722 is connected to the airbag 75. The outer contour of the conical cylinder 721 is provided with a spiral groove 78 with the same structure as the outer arc surface of the claw 74.

[0058] During operation, unlike the working state of the third clamping component 7, attention should be paid to the stress limit at the end of the tubular d material during the clamping and stretching process. Excessive inward squeezing force may cause the end to collapse, thereby having a negative impact on the clamping stability and the uniformity of stress in the subsequent tensile test. Therefore, in the process of the fourth clamping component 8 clamping the outer contour of the tubular d material through the claws 74, the air pressure formed after the airbag 75 is squeezed is used to expand the expansion ball 722 on the inner side of the conical tube 721, thereby expanding the end of the conical tube 721 outward and finally abutting against the inner wall of the tubular d material, providing an internal support effect from the inside. While improving the clamping stability, it also prevents the tubular d material itself from being deformed under stress, thereby improving the accuracy of the data on the stress condition of the subsequent tensile test.

[0059] In addition, the present invention also provides a test method of a hydrogen embrittlement test device for slow strain tensile test evaluation, comprising the following steps:

[0060] S1. Material selection: First, select appropriate sheet a, wire b, rod c or tubular d materials for hydrogen embrittlement test. The material of the selected material is one of structural steel, aluminum alloy or nickel alloy. When the selected material is contaminated by hydrogen during the manufacturing process, or is exposed to a hydrogen-rich gas environment during use, hydrogen embrittlement will occur. This phenomenon will greatly reduce the strength and toughness of the material, and even cause the material to break. The hydrogen embrittlement test simulates the actual production or use conditions of the material, which can provide data and theoretical and practical support for the structural strength of the material and subsequent maintenance and improvement.

[0061] S2. Clamping and positioning: After the material selection is completed, the outer disk 42 is rotated according to the shape of the material so that the clamping assembly corresponding to the material is in the working position. After the adjustment is completed, the locking between the outer disk 42 and the inner disk 41 is achieved through the positioning piece 44. Subsequently, the material is placed in the clamping assembly and the position is locked.

[0062] S3, tensile test: start the servo motor 3 to run, so that it drives the screw in the traction assembly 2 to rotate, and then drives the upper traction disk 4 to move upward through the fixed plate, and the lower traction disk 4 remains fixed on the test bench 1.

[0063] S4. Data acquisition: Various data during the traction and stretching process are recorded through multiple sensors, and the tensile strength of the material is calculated by a computer to obtain the slow strain stretching test data.

[0064] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A hydrogen embrittlement test device for slow strain tensile test evaluation, comprising a test bench (1), a traction assembly (2) and a servo motor (3), wherein the traction assembly (2) is fixedly mounted above the test bench (1), the traction assembly (2) comprises a screw, a slide rail, a slider and a fixing plate mounted on the slider, the servo motor (3) is fixedly mounted above the traction assembly (2), and the output shaft of the servo motor (3) is fixedly connected to the end of the screw in the traction assembly (2) through a coupling, characterized in that: A traction disk (4) is symmetrically mounted in the middle of the fixed plate in the traction assembly (2) and in the upper part of the test bench (1); the traction disk (4) comprises an inner disk (41) and an outer disk (42); the inner disk (41) is fixedly mounted, and the outer disk (42) is mounted on the inner disk (41) by means of rotational fit; a group of positioning seats (43) are mounted around the disk surface of the inner disk (41); positioning pieces (44) are mounted on the positioning seats (43) by means of rotational fit; and a positioning notch engaged with the positioning piece (44) is provided on the outer disk (42); A first clamping assembly (5), a second clamping assembly (6), a third clamping assembly (7) and a fourth clamping assembly (8) are fixedly mounted on the outer disk (42); the first clamping assembly (5), the second clamping assembly (6), the third clamping assembly (7) and the fourth clamping assembly (8) are circumferentially distributed on the outer disk (42); The first clamping assembly (5) and the second clamping assembly (6) are arranged opposite to each other. The main structures of the first clamping assembly (5) and the second clamping assembly (6) are both composed of two elastic plates (51) of the same structure. The first elastic plate (51) is fixedly mounted on the outer disk (42), and the second elastic plate (51) is fixedly mounted on the first elastic plate (51) by means of elastic bolts (52). The inner plate surface of the elastic plate (51) in the first clamping assembly (5) is provided with wavy tooth patterns (53) for clamping sheet (a) materials. The elastic plate (51) in the second clamping assembly (6) is provided with an elastic disk (54) for clamping filament (b) materials by means of rotational engagement. The third clamping assembly (7) and the fourth clamping assembly (8) are arranged opposite to each other. The main structures of the third clamping assembly (7) and the fourth clamping assembly (8) both include a clamp (71), a clamp plate (72), a clamp cylinder (73), a claw (74) and an air bag (75). The clamp (71) is fixedly mounted on the outer plate (42). The clamp plate (72) is fixedly mounted on the clamp (71). The central axis of the clamp plate (72) is perpendicular to the central axis of the outer plate (42). One end of the clamp cylinder (73) is mounted on the clamp plate (72) by means of rotational cooperation. The claw (74) is movably mounted in the clamp cylinder (73). The air bag (75) is circumferentially mounted at the middle position of the clamp cylinder (73). A flat tie rod (76) is fixedly mounted on the clamping plate (72), the flat tie rod (76) is arranged circumferentially, and a rubber ring (77) made of elastic material is installed between the plurality of flat tie rods (76), the claws (74) and the flat tie rods (76) are arranged at intervals, and the rubber ring (77) slides through the middle of the claws (74); The difference between the third clamping assembly (7) and the fourth clamping assembly (8) is that the third clamping assembly (7) is used to clamp columnar or rod-shaped (c) materials, and the fourth clamping assembly (8) is used to clamp tubular (d) materials; A hook claw (732) is movably mounted on the abutting cylinder (73) of the third clamping assembly (7), the end of the hook claw (732) is tilted to point toward the axis of the abutting cylinder (73), a lever (733) is hingedly mounted on one side of the hook claw (732), the middle portion of the lever (733) passes through the abutting cylinder (73), and the other end of the lever (733) abuts against the side wall of the airbag (75); A conical cylinder (721) is fixedly mounted on the abutment plate (72) of the fourth clamping assembly (8); the conical ends of the conical cylinder (721) are independent of each other; an expansion ball (722) is fixedly mounted on the bottom of the conical cylinder (721); the expansion ball (722) fills the inner cavity of the conical cylinder (721); the expansion ball (722) is connected to the airbag (75); and the outer contour of the conical cylinder (721) is provided with a spiral groove (78) having the same structure as the outer arc surface of the claw (74).

2. A hydrogen embrittlement testing device for slow strain tensile test evaluation according to claim 1, characterized in that: The elastic discs (54) are both semi-circular disc structures. The two elastic discs (54) are respectively mounted on the first and second elastic plates (51) by means of rotational fit, and thread-shaped grooves (55) adapted to the thread-shaped (b) material are symmetrically provided on the facing surfaces of the two elastic plates (51).

3. A hydrogen embrittlement testing device for slow strain tensile test evaluation according to claim 2, characterized in that: The filamentary grooves (55) are provided in a plurality of groups in a circumferential direction, each group of filamentary grooves (55) is provided with a plurality of grooves, and the inner groove surface of each groove of the filamentary groove (55) is a rough structure.

4. A hydrogen embrittlement testing device for slow strain tensile test evaluation according to claim 3, characterized in that: The claw (74) is an incomplete cylindrical structure, the central axis of the claw (74) coincides with the central axis of the abutting tube (73), and a spiral groove (78) for increasing contact surface pressure is arranged in a spiral manner on the inner arc surface of the claw (74).

5. A hydrogen embrittlement testing device for slow strain tensile test evaluation according to claim 4, characterized in that: The bottom of the inner arc surface of the abutting tube (73) and the outer arc surface of the abutting plate (72) are provided with mutually meshing threads, a slip ring (79) is fixedly installed at the outer arc surface of the claw (74), a step surface (731) with a gradually changing thickness is fixedly installed at the middle of the inner arc surface of the abutting tube (73), the slip ring (79) is in sliding contact with the step surface (731), and the slip ring (79) squeezes the air bag (75) during sliding.

6. A test method using the hydrogen embrittlement test device for slow strain tensile test evaluation according to claim 1, characterized in that: The method comprises the following steps: S1. Material selection: First, select appropriate sheet (a), wire (b), rod (c) or tube (d) materials for hydrogen embrittlement test. The material of the selected material is one of structural steel, aluminum alloy or nickel alloy; S2, clamping and positioning: after the material is selected, the outer disk (42) is rotated according to the shape of the material so that the clamping assembly corresponding to the material is in the working position. After the adjustment is completed, the outer disk (42) and the inner disk (41) are locked by the positioning piece (44). Then, the material is placed in the clamping assembly and the position is locked; S3, tensile test: the servo motor (3) is started to run, so that it drives the screw in the traction assembly (2) to rotate, and then drives the upper traction disc (4) to move upward through the fixed plate, and the lower traction disc (4) is still fixed on the test bench (1). At this time, the selected material is deformed under the action of the tensile force; S4. Data acquisition: Various data during the traction and stretching process are recorded through multiple sensors, and the tensile strength of the material is calculated by a computer to obtain the slow strain stretching test data.

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