Miniature sample clamping device based on uniaxial tensile test and use method thereof

Abstract

The invention relates to a miniature sample clamping device based on a uniaxial tensile test and a use method of the miniature sample clamping device. The miniature sample clamping device comprises an upper clamping assembly and a lower clamping assembly which are used for clamping a miniature sample; the guide piece is used for aligning the upper clamping assembly and the lower clamping assembly; the universal hinge is used for respectively connecting the upper clamping assembly and the lower clamping assembly with the tensile testing machine; the upper clamping assembly and the lower clamping assembly each comprise a clamping block, a gasket and a cover plate. A clamping groove matched with at least part of the end of the miniature sample in shape is formed in the clamping block, a containing space used for fixing the end of the miniature sample and gaskets on the two sides of the miniature sample is formed in the clamping groove, and the two sides of the clamping groove are fixed through cover plates. Compared with the prior art, the device can prevent the miniature sample from falling off, being placed incorrectly, slipping and the like in the tensile test process, and ensures the smooth proceeding of the tensile test and the accuracy of test data.

Description

Technical Field

[0001] The invention relates to the technical field of clamps, and in particular to a miniature sample clamping device based on a uniaxial tensile test and a use method thereof. Background Art

[0002] As a standard method for evaluating the mechanical properties of metal materials, traditional tensile testing plays a fundamental role in the development and quality control of engineering materials. According to the traditional tensile test method, the mechanical properties of metal materials are measured with large specimens, and the length of the parallel section of the specimen is generally in the range of 50-100mm. In addition, a large number of repetitive tests are required, which will lead to a large waste of metal materials.

[0003] The micro-specimen micro-tensile test method is a new test method. During the test, the sample size can be reduced to 1 / 5-1 / 10 of the conventional sample. The use of smaller miniature samples is conducive to saving metal materials and reducing test costs. In addition, since the size of the miniature sample is small, it is conducive to studying the mechanical properties of local area materials, such as the material in the heat affected zone of steel welding. Therefore, from the perspective of engineering application, the use of miniature samples for tensile testing can save metal materials and reduce costs.

[0004] However, there are many problems in the actual process of using miniature specimens for tensile testing. For example, if the size of the miniature specimen is too small, a small misalignment will produce a large bending strain during the tensile test, and the specimen is easily changed or damaged during clamping, all of which will affect the accuracy of the test results. In addition, if the size of the miniature specimen is too small, it will amplify the impact of human operation instability on the test results during the tensile test; the miniature specimen is prone to slipping during the tensile process, affecting the test results; and the miniature specimen cannot be directly tested on a general tensile testing machine due to its small size.

[0005] CN112730048A discloses a clamp for tensile testing and a method for fixing a tensile specimen in a tensile test, wherein the clamp for tensile testing includes a first clamping assembly for fixing one end of the tensile specimen and a second clamping assembly for fixing the other end; the first clamping assembly and the second clamping assembly are both composed of a first clamping outer plate, a second clamping outer plate and a clamping inner plate, and a smaller clamping inner plate is used to form a accommodating space for fixing the tensile specimen at the second end. However, the process of clamping the first clamping assembly and the second clamping assembly in the clamp provided by the tensile testing machine by the above-mentioned clamp for tensile testing completely relies on manual visual positioning, so it is impossible to ensure that the first clamping assembly and the second clamping assembly can be vertically aligned with the tensile testing machine, that is, it is impossible to ensure that the forces at both ends of the tensile specimen are on the same straight line, which may generate additional bending moment.

[0006] Therefore, there is still a need to develop a new type of micro-specimen clamping device for uniaxial tensile testing. Summary of the Invention

[0007] The purpose of the present invention is to overcome the defect of the prior art that a micro-specimen cannot be effectively fixed for tensile testing, and to provide a micro-specimen clamping device based on uniaxial tensile testing and its usage method.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] The present invention first provides a micro-specimen clamping device based on uniaxial tensile testing, which is used to clamp a micro-specimen for uniaxial tensile testing. The micro-specimen clamping device includes:

[0010] An upper clamping component for clamping one end of the micro-specimen;

[0011] A lower clamping component for clamping the other end of the micro-specimen;

[0012] A guiding member for aligning the upper clamping component and the lower clamping component before fixing the micro-specimen;

[0013] A universal hinge for connecting the upper clamping component and the lower clamping component to a tensile testing machine respectively;

[0014] Among them, both the upper clamping component and the lower clamping component include a clamping block, a gasket, and a cover plate detachably connected to both sides of the clamping block;

[0015] A clamping groove adapted to at least part of the end shape of the micro-specimen is formed in the clamping block. An accommodating space for fixing the end of the micro-specimen and the gaskets on both sides thereof is formed in the clamping groove, and both sides of the clamping groove are fixed by the cover plate.

[0016] Further, the micro-specimen includes square clamping sections at both ends and a middle parallel section located between the square clamping sections, and a transition curve section is between the square clamping section and the middle parallel section.

[0017] Further, the shape of the clamping groove is adapted to at least the square clamping section, the transition curve section, and part of the middle parallel section of the micro-specimen.

[0018] Further, the shape of the gasket is adapted to at least the square clamping section and part of the transition curve section of the micro-specimen.

[0019] Further, the sum of the thickness of the micro-specimen and the thicknesses of the gaskets on both sides thereof is the same as the thickness of the clamping groove.

[0020] Further, the sum of the thickness of the clamping groove and the thicknesses of the cover plates on both sides thereof is not less than the thickness of the clamping block.

[0021] Further, threaded holes are correspondingly provided on both the clamping block and the cover plate.

[0022] Furthermore, the clamping blocks are tightly connected to the cover plates on both sides through the cooperation of bolts and nuts.

[0023] Further, the clamping block includes a first positioning portion, a second positioning portion and a connecting portion which are integrally connected, and the first positioning portion and the second positioning portion are symmetrically arranged with respect to the connecting portion.

[0024] Further, a first clamping portion and a second clamping portion are symmetrically arranged in the space formed between the first positioning portion and the second positioning portion, and a clamping groove is formed between the first clamping portion and the second clamping portion.

[0025] Furthermore, through holes for installing the guiding members are provided on both the first positioning portion and the second positioning portion; the guiding members can penetrate through the guiding member installation through holes on the corresponding sides of the upper clamping assembly and the lower clamping assembly simultaneously before fixing the micro-specimen.

[0026] Furthermore, mounting holes adapted to the universal hinges are provided on the connecting portions of the clamping blocks.

[0027] Further, one end of the universal hinge is threadedly connected to the clamping block, and the other end of the universal hinge is threadedly connected to the tensile testing machine.

[0028] Further, the micro-specimen clamping device can be used for uniaxial tensile testing of micro-specimens with a length of 15 - 30 mm, a width of 2 - 3 mm, and a thickness of 1 - 8 mm.

[0029] Further, the upper clamping assembly, the lower clamping assembly and the guiding members of the micro-specimen clamping device are all made of 42CrMo steel, which has good mechanical properties and can support tensile testing of high-strength metal materials.

[0030] The present invention also provides a method for using a micro-specimen clamping device based on uniaxial tensile testing, including the following steps:

[0031] S1: Pass the guiding member through the upper clamping assembly and the lower clamping assembly to align the two;

[0032] S2: Place the micro-specimen and the gaskets on both sides thereof in the clamping groove of the clamping block, and then tightly install the cover plates on both sides with the clamping block;

[0033] S3: Connect the upper clamping assembly and the lower clamping assembly to the tensile testing machine through the universal hinges respectively, and remove the guiding member to perform uniaxial tensile testing.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The micro-specimen clamping device of the present invention fixes both ends of the tensile micro-specimen through the upper clamping component and the lower clamping component. The clamping groove of the clamping component is adapted to the end of the micro-specimen, which can prevent the micro-specimen from falling off, being misaligned, and slipping during the tensile test, ensuring the smooth progress of the tensile test. At the same time, before fixing the specimen, it is aligned through the guiding member, and the clamping component is connected to the testing machine through a universal hinge, which can ensure the axiality of the tensile specimen, and no bending moment will be generated due to misalignment, ensuring the accuracy of the test data.

[0036] (2) The clamping groove provided in the clamping block of the present invention has a shape of the end of the specimen, a transition curve, and a partial parallel length, which can well fix the tensile specimen, prevent the specimen from slipping, and the reasonable transition curve can avoid the phenomenon of stress concentration at the clamping end, preventing damage from occurring at the end of the specimen.

[0037] (3) The present invention utilizes the universal hinge to play a role in reducing eccentricity, which can ensure that the specimen is tensioned in the axial direction, so that the specimen is not affected by bending moment during the tensile test.

[0038] (4) The micro-specimen clamping device of the present invention can be adapted to tensile micro-specimens of different thicknesses by changing the thickness of the gasket. As long as it is ensured that the sum of the thicknesses of the micro-specimen and the gaskets on both sides is consistent with the thickness of the clamping groove, it can be ensured that no additional bending moment is generated during the tensile process of the specimen.

[0039] (5) The clamping component of the present invention is small in volume and very light in weight. The micro-specimen can be fixed first and then connected to the testing machine, and the operation is simple. Brief Description of the Drawings

[0040] Figure 1 is an exploded schematic view of the micro-specimen clamping device of the present invention.

[0041] Figure 2 is a schematic structural view of the micro-specimen in Embodiment 2 of the present invention.

[0042] Figure 3 is a schematic structural view of the clamping block in Embodiment 5 of the present invention.

[0043] Figure 4 is a schematic flow chart of installing the micro-specimen in the usage method of the present invention.

[0044] Figure 5 is a schematic flow chart of installing the universal hinge and removing the guiding member in the usage method of the present invention.

[0045] Figure 6 is a schematic dimension view of the micro-specimen in Embodiment 6 of the present invention.

[0046] Figure 7Schematic diagram of the loading device and data acquisition device for the tensile test in Embodiment 6 of the present invention.

[0047] Figure 8 Schematic diagrams of the micro-specimen in different states during the tensile test in Embodiment 6 of the present invention.

[0048] Figure 9 Engineering stress-strain relationship curve of the micro-specimen in Embodiment 6 of the present invention.

[0049] Description of the markings in the figure:

[0050] 1 - Micro-specimen, 11 - Square clamping section, 12 - Middle parallel section, 13 - Transition curve section;

[0051] 2 - Clamping block, 21 - Clamping groove, 22 - First positioning part, 23 - Second positioning part, 24 - Connecting part, 241 - Mounting hole, 25 - First clamping part, 26 - Second clamping part, 27 - Guide part mounting through hole;

[0052] 3 - Spacer;

[0053] 4 - Cover plate;

[0054] 5 - Guide part;

[0055] 6 - Universal hinge;

[0056] 7 - Bolt;

[0057] 8 - Nut. Detailed implementation manners

[0058] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and the detailed implementation manners and specific operation processes are given, but the protection scope of the present invention is not limited to the following embodiments.

[0059] In the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention; the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance; in addition, unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" 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 an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0061] Embodiment 1:

[0062] This embodiment provides a micro-specimen clamping device based on a uniaxial tensile test, which is used to clamp the micro-specimen 1 for a uniaxial tensile test. The micro-specimen clamping device includes an upper clamping assembly, a lower clamping assembly, a guide member 5 and a universal hinge 6.

[0063] As Figure 1 shown, the upper clamping assembly of this embodiment is used to clamp one end of the micro-specimen 1, and the lower clamping assembly is used to clamp the other end of the micro-specimen 1. The guide member 5 is used to align the upper clamping assembly and the lower clamping assembly before fixing the micro-specimen 1, and the universal hinge 6 is used to connect the upper clamping assembly and the lower clamping assembly to the tensile testing machine respectively.

[0064] Among them, both the upper clamping assembly and the lower clamping assembly of this embodiment include a clamping block 2, a gasket 3, and a cover plate 4 that can be detachably connected to both sides of the clamping block 2. A clamping groove 21 adapted to at least partially the end shape of the micro-specimen 1 is formed in the clamping block 2. An accommodation space for fixing the end of the micro-specimen 1 and the gaskets 3 on both sides thereof is formed in the clamping groove 21, and both sides of the clamping groove 21 are fixed by the cover plate 4.

[0065] The usage method of the micro-specimen clamping device in this embodiment specifically includes the following steps:

[0066] S1: Pass the guide member 5 through the upper clamping assembly and the lower clamping assembly to align the two;

[0067] S2: Place the micro-specimen 1 and the gaskets 3 on both sides thereof in the clamping grooves 21 of the clamping block 2, and then fasten the cover plates 4 on both sides to the clamping block 2.

[0068] S3: Connect the upper clamping assembly and the lower clamping assembly to the tensile testing machine through universal hinges 6 respectively, and remove the guiding member 5 to conduct a uniaxial tensile test.

[0069] The micro-specimen clamping device of the present invention fixes both ends of the tensile micro-specimen 1 through the upper clamping assembly and the lower clamping assembly. The clamping grooves 21 of the clamping assembly are adapted to the ends of the micro-specimen 1, which can prevent the micro-specimen 1 from falling off, being misaligned, and slipping during the tensile test, ensuring the smooth progress of the tensile test. At the same time, before fixing the micro-specimen 1, it is aligned through the guiding member 5, and the clamping assembly and the testing machine are connected through the universal hinge 6, which can ensure the axiality of the tensile specimen and the accuracy of the test data.

[0070] Example 2:

[0071] This example provides a micro-specimen clamping device based on a uniaxial tensile test for clamping the micro-specimen 1 to conduct a uniaxial tensile test. The micro-specimen clamping device includes an upper clamping assembly, a lower clamping assembly, a guiding member 5, and a universal hinge 6.

[0072] The difference from Example 1 is that, as Figure 2 shown, the micro-specimen 1 in this example is an overall dumbbell-shaped specimen. The micro-specimen 1 specifically includes square clamping sections 11 at both ends and a middle parallel section 12 located between the square clamping sections 11. A transition curve section 13 is provided between the square clamping section 11 and the middle parallel section 12, and the transition curve section 13 can avoid the stress concentration phenomenon at the clamping end.

[0073] The shape of the clamping groove 21 in this example is adapted to at least the square clamping section 11, the transition curve section 13, and a part of the middle parallel section 12 of the micro-specimen 1, and the shape of the gasket 3 is adapted to at least the square clamping section 11 and a part of the transition curve section 13 of the micro-specimen 1.

[0074] The clamping groove 21 in this example can prevent the micro-specimen 1 from falling off, being misaligned, and slipping during the tensile test, ensuring the smooth progress of the tensile test and the accuracy of the test data.

[0075] Example 3:

[0076] This example provides a micro-specimen clamping device based on a uniaxial tensile test for clamping the micro-specimen 1 to conduct a uniaxial tensile test. The micro-specimen clamping device includes an upper clamping assembly, a lower clamping assembly, a guiding member 5, and a universal hinge 6.

[0077] The difference from Embodiment 1 is that the sum of the thickness of the micro-specimen 1 and the thicknesses of the gaskets 3 on both sides thereof in this embodiment is consistent with the thickness of the clamping groove 21.

[0078] The sum of the thickness of the clamping groove 21 and the thicknesses of the cover plates 4 on both sides thereof in this embodiment is not less than the thickness of the clamping block 2, that is, after the cover plates 4 on both sides are connected and fixed to the clamping block 2, they are flush with or slightly protrude from the clamping block 2.

[0079] Embodiment 4:

[0080] This embodiment provides a micro-specimen clamping device based on a uniaxial tensile test for clamping the micro-specimen 1 for a uniaxial tensile test. The micro-specimen clamping device includes an upper clamping assembly, a lower clamping assembly, a guide member 5 and a universal hinge 6.

[0081] The difference from Embodiment 1 is that threaded holes are correspondingly formed in both the clamping block 2 and the cover plate 4 in this embodiment, and the clamping block 2 is connected and fastened to the cover plates 4 on both sides through the cooperation of bolts 7 and nuts 8.

[0082] Embodiment 5:

[0083] This embodiment provides a micro-specimen clamping device based on a uniaxial tensile test for clamping the micro-specimen 1 for a uniaxial tensile test. The micro-specimen clamping device includes an upper clamping assembly, a lower clamping assembly, a guide member 5 and a universal hinge 6.

[0084] The difference from Embodiment 1 is that, as Figure 3 shown, the clamping block 2 in this embodiment includes a first positioning portion 22, a second positioning portion 23 and a connecting portion 24 which are integrally connected, and the first positioning portion 22 and the second positioning portion 23 are symmetrically arranged with respect to the connecting portion 24. A first clamping portion 25 and a second clamping portion 26 are symmetrically arranged in the space formed between the first positioning portion 22 and the second positioning portion 23, and a clamping groove 21 is formed between the first clamping portion 25 and the second clamping portion 26.

[0085] Guide member installation through holes 27 are formed in both the first positioning portion 22 and the second positioning portion 23 of this embodiment. Before fixing the micro-specimen 1, the guide member 5 can penetrate through the guide member installation through holes 27 on the corresponding sides of the upper clamping assembly and the lower clamping assembly at the same time to play an alignment role.

[0086] Mounting holes 241 adapted to the universal hinge 6 are formed in the connecting portion 24 of the clamping block 2 in this embodiment. One end of the universal hinge 6 is threadedly connected to the clamping block 2, and the other end of the universal hinge 6 is threadedly connected to the tensile testing machine. The universal hinge 6 is used to reduce eccentricity, which can ensure that the micro-specimen 1 is tensioned in the axial direction and the micro-specimen 1 is not subjected to bending moment during the tensile test.

[0087] Embodiment 6:

[0088] This embodiment provides a micro-specimen clamping device based on a uniaxial tensile test, as well as its specific usage method and principle. The micro-specimen clamping device of this embodiment specifically includes an upper clamping assembly for fixing one end of the micro-specimen 1, a lower clamping assembly for fixing the other end of the micro-specimen 1, a guide member 5 for aligning the upper clamping assembly and the lower clamping assembly, and a universal hinge 6 for connecting the clamping assembly and the tensile testing machine. The upper clamping assembly, the lower clamping assembly, and the guide member 5 of this embodiment are all made of 42CrMo steel, which has good mechanical properties and can support tensile tests of high-strength metal materials.

[0089] Both the upper clamping assembly and the lower clamping assembly include a clamping block 2, a gasket 3, a cover plate 4, and a bolt 7. A clamping groove 21 is machined in the clamping block 2, and its shape is the end part, transition curve, and part of the parallel length of the micro-specimen 1, forming an accommodating space for fixing the micro-specimen 1, the gasket 3, and the cover plate 4, which can fix the micro-specimen 1 and ensure the alignment of the micro-specimen 1 in the clamping assembly. The clamping grooves 21 on both sides in the clamping block 2 are through, and when fixing the micro-specimen 1, gaskets 3 and cover plates 4 are installed on both sides. The thickness of the micro-specimen 1 plus the thickness of the two gaskets 3 should be the same as the thickness of the clamping groove 21 in the clamping block 2.

[0090] This embodiment has two guide members 5 of the same size, which are respectively arranged at the holes at both ends of the clamping assembly, so as to facilitate the installation of the micro-specimen 1 between the upper clamping assembly and the lower clamping assembly, and the installation of the upper clamping assembly and the lower clamping assembly on the tensile testing machine. The guide member 5 should be installed before fixing the micro-specimen 1 and removed before the start of the tensile test. The guide member 5 of this embodiment is a cylindrical long rod.

[0091] This embodiment has two universal hinges 6, which are respectively arranged at the connection between the clamping assembly and the testing machine, and are used to connect the clamping assembly and the testing machine, which can ensure the axiality of the micro-specimen 1 during the tensile process and prevent bending moment caused by misalignment.

[0092] The specific usage method of the micro-specimen clamping device of this embodiment is as follows:

[0093] As Figures 4 - 5 shown, when conducting a uniaxial tensile test on the micro-specimen 1, first install the guide member 5 into the clamping block 2 and penetrate the clamping blocks 2 of the upper clamping assembly and the lower clamping assembly at the same time. Then install the micro-specimen 1, the gaskets 3 and the cover plates 4 on both sides, and fix them with bolts 7 and nuts 8. Then install the clamping block 2 on the tensile end of the testing machine by respectively setting the universal hinge 6. Finally, remove the guide member 5, and then the uniaxial tensile test can be started.

[0094] The working principle of the micro-specimen clamping device of this embodiment is:

[0095] In the clamping block 2 of this embodiment, a clamping groove 21 is provided, and its shape is adapted to the end part, transition curve and partial parallel length of the micro-specimen 1, which can fix the tensile specimen well and prevent the specimen from slipping; the reasonable transition curve can avoid the stress concentration phenomenon at the clamping end and prevent the end part of the specimen from being damaged; the use of the universal hinge 6 can play a role in reducing eccentricity, ensuring that the micro-specimen 1 is subjected to tensile force in the axial direction and the micro-specimen 1 is not subjected to bending moment during the tensile test. When it is necessary to test micro-specimens 1 with different thicknesses, it is only necessary to change the thickness of the gasket 3 and ensure that the sum of the thicknesses of the micro-specimen 1 and the two-sided gaskets 3 is consistent with the thickness of the clamping groove 21, so as to be applicable to micro-specimens 1 with different thicknesses and ensure that no additional bending moment is generated during the uniaxial tension of the micro-specimen 1.

[0096] In this embodiment, a uniaxial tensile test is specifically carried out taking the micro-specimen 1 taken from Q460 high-strength steel as an example. As Figure 6 shown, the overall length of the test micro-specimen 1 is 26 mm, and the overall thickness is 1 mm; the length of the parallel section in the middle of the micro-specimen 1 is about 11.4 mm, and the width of the parallel section in the middle is 2.5 mm. The thickness of the gasket 3 used in this test is 4.5 mm. The size of the micro-specimen 1 can be adjusted adaptively according to the test requirements and the size of the clamping block 2.

[0097] Figure 7 The loading device and data acquisition device for the tensile test of this embodiment are shown. As can be seen from the figure, the tensile test of this embodiment is carried out on a Tinius Olsen 100ST electronic universal testing machine. The test adopts the displacement control mode and is subjected to quasi-static loading at a rate of 0.2 mm / min. The gauge length of the micro-specimen 1 is 9.0 mm, and the deformation of the gauge section is measured non-contact by the DIC technology. The image acquisition interval is set to 1000 ms; the load at the clamping end is measured by a force sensor with a rated range of 10 kN, and the acquisition frequency is set to 1 Hz to ensure synchronous acquisition with the deformation data of the gauge section. The states of the micro-specimen 1 before and after tensile failure are as Figure 8 shown, and it can be seen that the plastic deformation of the micro-specimen 1 is mainly concentrated in the parallel section, and the final fracture also occurs in this area.

[0098] The engineering stress-strain relationship curve of Q460 high-strength steel obtained from the tensile test of this embodiment is as Figure 9 shown. It can be seen that the yield strength of Q460 steel is 490 MPa, the tensile strength is 653 MPa, and the elongation after fracture is 18.7%. The results show that the micro-specimen clamping device and tensile test system based on the present invention can effectively obtain accurate and reliable mechanical properties of the test materials.

[0099] The above description of the embodiments is provided to enable those of ordinary skill in the art to understand and use the invention. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the present invention is not limited to the above embodiments, and all improvements and modifications made by those skilled in the art without departing from the scope of the present invention according to the disclosure of the present invention should be within the protection scope of the present invention.

Claims

1. A miniature specimen clamping device based on a uniaxial tensile test, used for clamping a miniature specimen (1) for a uniaxial tensile test, characterized in that: The miniature specimen clamping device comprises: An upper clamping assembly for clamping one end of a miniature specimen (1); A lower clamping assembly for clamping the other end of the miniature specimen (1); A guide member (5) for aligning an upper clamping assembly with a lower clamping assembly before fixing the miniature specimen (1); A universal hinge (6) for connecting the upper clamping assembly and the lower clamping assembly to the tensile testing machine respectively; Wherein, the upper clamping assembly and the lower clamping assembly both comprise a clamping block (2), a gasket (3), and a cover plate (4) detachably connected to both sides of the clamping block (2); The clamping block (2) is provided with a clamping groove (21) adapted to the shape of at least part of the end of the miniature specimen (1), and a receiving space for fixing the end of the miniature specimen (1) and gaskets (3) on both sides thereof is formed in the clamping groove (21), and both sides of the clamping groove (21) are fixed by a cover plate (4).

2. A miniature specimen clamping device based on uniaxial tensile test according to claim 1, characterized in that: The miniature specimen (1) comprises square clamping sections (11) at both ends and a middle parallel section (12) located between the square clamping sections (11); a transition curve section (13) is located between the square clamping sections (11) and the middle parallel section (12).

3. A miniature specimen clamping device based on uniaxial tensile test according to claim 2, characterized in that: The shape of the clamping groove (21) is at least adapted to the square clamping section (11), the transition curve section (13) and part of the middle parallel section (12) of the miniature specimen (1); The shape of the gasket (3) is at least adapted to the square clamping section (11) and part of the transition curve section (13) of the miniature specimen (1).

4. The miniature specimen clamping device based on uniaxial tensile test according to claim 1 is characterized in that: The thickness of the miniature specimen (1) is consistent with the sum of the thickness of the gaskets (3) on both sides thereof and the thickness of the clamping groove (21).

5. The miniature specimen clamping device based on uniaxial tensile test according to claim 1 is characterized in that: The sum of the thickness of the clamping groove (21) and the thickness of the cover plates (4) on both sides thereof is not less than the thickness of the clamping block (2).

6. The miniature specimen clamping device based on uniaxial tensile test according to claim 1 is characterized in that: The clamping block (2) and the cover plate (4) are both provided with threaded holes correspondingly; The clamping blocks (2) are connected and fastened to the cover plates (4) on both sides by means of the cooperation of bolts (7) and nuts (8).

7. The miniature specimen clamping device based on uniaxial tensile test according to claim 1 is characterized in that: The clamping block (2) comprises a first positioning portion (22), a second positioning portion (23) and a connecting portion (24) which are integrally connected, and the first positioning portion (22) and the second positioning portion (23) are symmetrically arranged with respect to the connecting portion (24); A first clamping portion (25) and a second clamping portion (26) are symmetrically arranged in a space formed between the first positioning portion (22) and the second positioning portion (23), and a clamping groove (21) is formed between the first clamping portion (25) and the second clamping portion (26).

8. The miniature specimen clamping device based on uniaxial tensile test according to claim 7, characterized in that: The first positioning portion (22) and the second positioning portion (23) are both provided with guide member installation through holes (27); The guide member (5) can simultaneously penetrate the guide member installation through holes (27) on the corresponding sides of the upper clamping assembly and the lower clamping assembly before fixing the miniature specimen (1); The connection part (24) of the clamping block (2) is provided with a mounting hole (241) adapted to the universal hinge (6).

9. The miniature specimen clamping device based on uniaxial tensile test according to claim 1, characterized in that: One end of the universal hinge (6) is threadedly connected to the clamping block (2), and the other end of the universal hinge (6) is threadedly connected to the tensile testing machine.

10. A method for using the miniature specimen clamping device based on uniaxial tensile test according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: passing the guide member (5) through the upper clamping assembly and the lower clamping assembly to align the two; S2: placing the miniature specimen (1) and the gaskets (3) on both sides thereof in the clamping grooves (21) of the clamping block (2), and then installing and fastening the cover plates (4) on both sides to the clamping block (2); S3: The upper clamping assembly and the lower clamping assembly are respectively connected to the tensile testing machine via the universal joint (6), and the guide member (5) is removed to perform the uniaxial tensile test.

Images