Clamp for improving high-temperature shear strength of welding interface of composite material

Abstract

The utility model relates to a clamp for high-temperature shear strength of a composite material welding interface, and belongs to the technical field of material detection. The clamp comprises an upper clamp body and a lower clamp body, the upper clamp body sequentially comprises an upper clamping rod, an upper platform and an upper vertical block from top to bottom, the cross section of the upper clamping rod and the cross section of the upper platform are circular, the cross section of the upper vertical block is semicircular, and the peripheral face of the upper platform coincides with the peripheral face of the upper vertical block. The lower clamp sequentially comprises a lower vertical block, a lower platform and a lower clamping rod from top to bottom, the sections of the lower clamping rod and the lower platform are circular, the section of the lower vertical block is semicircular, and the peripheral surfaces of the lower platform and the lower vertical block coincide; the arc-shaped bulge directions of the lower vertical block and the upper vertical block are opposite; a through groove is formed in the lower vertical block, and the center line of the through groove is parallel to the horizontal plane. The clamp is simple in structure, accurate in shear strength test result and suitable for a composite sample or a sample with a small size.

Description

Technical Field

[0001] This utility model relates to the field of materials testing technology, and in particular to a fixture for high-temperature shear strength testing of composite material welding interfaces. Background Technology

[0002] Welding is widely used in some fields to join different or the same materials to meet the structural and performance requirements of key components. Therefore, it is crucial to explore the strength of the weld interface and select different welding process parameters according to different needs, which can provide scientific data reference for actual needs.

[0003] The determination of shear strength at the sample interface depends on the sample size and the testing environment. Therefore, different shear samples require matching fixtures according to actual and testing requirements; moreover, existing fixture structures are relatively complex and are suitable for larger samples or specimens. Utility Model Content

[0004] Based on the above analysis, the present invention aims to provide a fixture for high-temperature shear strength testing of composite material welding interfaces. It has a simple structure, provides accurate shear strength test results, and is suitable for small-sized composite samples or specimens.

[0005] On the one hand, this utility model provides a fixture for improving the high-temperature shear strength of composite material welding interfaces, the fixture comprising an upper fixture and a lower fixture.

[0006] The upper clamp consists of an upper clamping rod, an upper platform, and an upper upright block from top to bottom. The upper clamping rod and the upper platform have circular cross-sections, and the upper upright block has a semi-circular cross-section. The outer circumferential surfaces of the upper platform and the upper upright block coincide.

[0007] The lower clamp includes, from top to bottom, a lower upright block, a lower platform, and a lower clamping rod. The lower clamping rod and the lower platform have circular cross-sections, and the lower upright block has a semi-circular cross-section. The outer circumferential surfaces of the lower platform and the lower upright block coincide. Furthermore, the arcuate protrusions of the lower upright block and the upper upright block are in opposite directions.

[0008] A radial through groove is provided on the lower upright block.

[0009] Furthermore, the upper clamping rod, the upper platform, the upper upright block, the lower upright block, the lower platform, and the lower clamping rod are all coaxially arranged.

[0010] Furthermore, the upper clamping rod, the upper platform, and the upper upright block are integrally formed, and the lower upright block, the lower platform, and the lower clamping rod are integrally formed.

[0011] Furthermore, the upper clamping rod is connected to the upper platform by a threaded connection; the lower clamping rod is connected to the lower platform by a threaded connection.

[0012] Furthermore, the upper clamping rod and the lower clamping rod have the same diameter, and the upper platform and the lower platform have the same diameter.

[0013] Furthermore, the diameter of the upper clamping rod is smaller than the diameter of the upper platform, and the diameter of the lower clamping rod is smaller than the diameter of the lower platform.

[0014] Furthermore, the cross-section of the through groove is circular or quadrilateral.

[0015] Furthermore, a fixing block is provided in the through groove, the fixing block corresponds one-to-one with the through groove, and a fixing groove for fixing the composite sample is opened on the fixing block.

[0016] Furthermore, when the cross-section of the through groove is circular, multiple limiting blocks are provided on the fixing block, and a groove for fixing the limiting blocks is provided in the through groove.

[0017] Furthermore, the distance between the upper block and the lower block is 0.5-1mm.

[0018] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0019] 1. In this utility model, the fixture consists of an upper fixture and a lower fixture. The upper fixture includes an upper clamping rod, an upper platform and an upper upright block. The lower fixture includes a lower upright block, a lower platform and a lower clamping rod. A through groove is provided on the lower upright block for placing and fixing the composite sample. During use, pressure is used to bring the upper fixture and the lower fixture closer together and to destroy the composite sample to determine the shear strength.

[0020] 2. The fixture provided by this utility model has a simple structure and can not only test the shear strength of composite materials or specimens at room temperature, but also place the fixture in a heating device to test the shear strength of composite materials or specimens at high temperature. In addition, the fixture has a simple structure, accurate shear strength test results, and is suitable for small-sized composite samples or specimens.

[0021] 3. A through groove is provided on the lower upright block of the lower fixture, and a fixing block is provided in the through groove. The fixing block corresponds one-to-one with the through groove, and a fixing groove for fixing the composite sample is provided on the fixing block. Different fixing blocks can be replaced according to the specifications of the composite sample, and composite samples or specimens of various specifications can be tested.

[0022] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages will become apparent from the description or be learned by practicing the invention. The objectives and other advantages of this invention can be realized and obtained from the description and accompanying drawings, which are particularly pointed out. Attached Figure Description

[0023] The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0024] Figure 1 This is a schematic diagram of the composite sample.

[0025] Figure 2 for Figure 1 Left side view;

[0026] Figure 3 This is a schematic diagram of the assembly structure of the upper and lower clamps;

[0027] Figure 4 for Figure 3 Left side view;

[0028] Figure 5 This is a schematic diagram showing the position of the fixed block;

[0029] Figure label:

[0030] 1. Composite sample; 11. First sample; 12. Second sample; 2. Upper clamp; 21. Upper clamping rod; 22. Upper platform; 23. Upper upright block; 3. Lower clamp; 31. Lower upright block; 32. Lower platform; 33. Lower clamping rod; 4. Through groove; 5. Fixing block; 51. Fixing groove; 52. Limiting block. Detailed Implementation

[0031] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0032] With the continuous development of technology, composite materials are commonly used in some fields. Different or identical materials are joined mainly through welding technology. It is necessary to ensure the shear strength of composite materials, especially the shear strength at high temperatures, and to adjust the welding process parameters based on the test results.

[0033] The determination of shear strength at the sample interface depends on the sample size and the testing environment. Therefore, different shear samples require matching fixtures according to actual and testing requirements; moreover, existing fixture structures are relatively complex and are suitable for larger samples or specimens.

[0034] Therefore, this utility model provides a fixture for improving the high-temperature shear strength of composite material welding interfaces, the fixture comprising an upper fixture 2 and a lower fixture 3.

[0035] The upper clamp 2 includes, from top to bottom, an upper clamping rod 21, an upper platform 22, and an upper upright block 23. The upper clamping rod 21 and the upper platform 22 have circular cross-sections, and the upper upright block 23 has a semi-circular cross-section. The outer circumferential surfaces of the upper platform 22 and the upper upright block 23 coincide.

[0036] The lower clamp 3 includes, from top to bottom, a lower upright block 31, a lower platform 32, and a lower clamping rod 33. The lower clamping rod 33 and the lower platform 32 have circular cross-sections, and the lower upright block 31 has a semi-circular cross-section. The outer circumferential surfaces of the lower platform 32 and the lower upright block 31 coincide. Furthermore, the arcuate protrusions of the lower upright block 31 and the upper upright block 23 are in opposite directions.

[0037] A through groove 4 is provided on the lower upright block 31, and the center line of the through groove 4 is parallel to the horizontal plane.

[0038] Compared with the prior art, the fixture provided by this utility model consists of an upper fixture 2 and a lower fixture 3. The upper fixture 2 includes an upper clamping rod 21, an upper platform 22 and an upper upright block 23. The lower fixture 3 includes a lower upright block 31, a lower platform 32 and a lower clamping rod 33. A through groove 4 is provided on the lower upright block 31 for placing and fixing the composite sample 1. During use, pressure is used to bring the upper fixture 2 and the lower fixture 3 closer together and to break the composite sample 1 to determine the shear strength.

[0039] The fixture provided by this utility model has a simple structure and can not only test the shear strength of composite materials or specimens at room temperature, but also place the fixture in a heating device to test the shear strength of composite materials or specimens at high temperature. In addition, the fixture has a simple structure, accurate shear strength test results, and is suitable for small-sized composite samples or specimens.

[0040] Install the fixture onto the test equipment. The installation process is as follows:

[0041] The upper clamping rod 21 of the upper clamp 2 is clamped onto the upper clamp of the test equipment and locked and fixed. In the vertical direction, the upper clamp 2 consists of the upper clamping rod 21, the upper platform 22 and the upper block 23 from top to bottom.

[0042] Then, the lower clamping rod 33 of the lower clamp 3 is clamped onto the lower clamp of the testing equipment and locked in place. In the vertical direction, the lower clamp 3 consists of the lower upright block 31, the lower platform 32 and the lower clamping rod 33 from top to bottom. Then, one end of the composite sample 1 (or sample) is placed in the through groove 4, and the interface of the composite sample 1 is flush with the side of the lower upright block 31.

[0043] Testing process:

[0044] The fixture provided by this utility model can be placed at room temperature to test room temperature shear strength, or placed in a heating furnace to test high temperature shear strength. By applying pressure, the upper fixture 2 and the lower fixture 3 are slowly brought closer together. The upper fixture 2 touches one end of the composite sample 1 or the sample (i.e., the end of the composite sample 1 or the sample exposed outside the through groove 4). The pressure is further increased to destroy the composite sample 1 or the sample. The maximum force is recorded, and the shear strength is the maximum force F / interface area.

[0045] During the high-temperature test, first adjust the upper clamp and its lifting mechanism to adjust the distance between the upper clamp 2 and the lower clamp 3, ensuring that the upper clamp 2 is almost in contact with the composite sample (i.e., the distance between the upper block 23 and the composite sample 1 is greater than 1 mm), but not in direct contact with the sample. After reaching the specified temperature, maintain the temperature before performing compression shearing, and record the maximum force. The shear strength is calculated as the maximum force F / interface area.

[0046] Specifically, the upper clamping rod 21, the upper platform 22, the upper upright block 23, the lower upright block 31, the lower platform 32, and the lower clamping rod 33 are all coaxially arranged.

[0047] It should be noted that in this utility model, it is necessary to ensure the coaxiality of the upper clamp 2, the lower clamp 3 and the composite sample 1, that is, the upper clamp rod 21, the upper platform 22, the upper upright block 23, the lower upright block 31, the lower platform 32 and the lower clamp rod 33 are all coaxially arranged, and their axes pass through the composite interface of the composite sample 1, that is, the axes of the upper clamp 2 and the lower clamp 3 coincide with the center line of the composite interface.

[0048] Ensuring the coaxiality of the fixture and composite specimen 1, and guaranteeing that the fixture and composite specimen 1 do not shift during the test, will better ensure the accuracy of the shear strength or data.

[0049] Specifically, the upper clamping rod 21, the upper platform 22, and the upper upright block 23 are integrally formed, and the lower upright block 31, the lower platform 32, and the lower clamping rod 33 are integrally formed.

[0050] Specifically, the upper clamping rod 21 is connected to the upper platform 22 by a threaded connection; the lower clamping rod 33 is connected to the lower platform 32 by a threaded connection.

[0051] It should be noted that in this utility model, the upper clamp 2 and the upper platform 22 are integrally formed, resulting in high overall strength. That is, the upper clamping rod 21, the upper platform 22, and the upper upright block 23 are integrally formed, as are the lower upright block 31, the lower platform 32, and the lower clamping rod 33. To meet the needs of different testing equipment, the connection between the upper clamping rod 21 and the upper platform 22, and between the lower clamping rod 33 and the lower platform 32, can also be a threaded connection, facilitating the replacement of upper clamping rods 21 and lower clamping rods 33 of different lengths.

[0052] Specifically, the upper clamping rod 21 and the lower clamping rod 33 have the same diameter, and the upper platform 22 and the lower platform 32 have the same diameter.

[0053] Specifically, the diameter of the upper clamping rod 21 is smaller than the diameter of the upper platform 22, and the diameter of the lower clamping rod 33 is smaller than the diameter of the lower platform 32.

[0054] It should be noted that in this invention, the upper clamping rod 21 and the lower clamping rod 33 primarily function as clamping rods, with one end connected to the clamping head of the equipment and the other end connected to the upper platform 22 and the lower platform 32, facilitating pressure transmission. The upper platform 22 and the lower platform 32 mainly serve to place or fix the composite sample 1, requiring specific dimensions and strength, and ensuring minimal deformation at high temperatures. Therefore, in this invention, the upper clamping rod 21 and the lower clamping rod 33 have the same diameter, as do the upper platform 22 and the lower platform 32. Furthermore, the diameter of the upper clamping rod 21 is smaller than the diameter of the upper platform 22, and the diameter of the lower clamping rod 33 is smaller than the diameter of the lower platform 32.

[0055] Specifically, the cross-section of the through groove 4 is circular or quadrilateral.

[0056] It should be noted that in this invention, a through groove 4 is provided on the lower support block 31, and the center line of the through groove 4 is parallel to the horizontal plane, that is, the through groove 4 on the lower support block 31 is a radial through groove 4. The main function of the through groove 4 is to place and fix one end of the composite sample 1, and to facilitate the removal of the broken sample after the test. In this invention, the cross-section of the through groove 4 is circular or quadrilateral, and the appropriate cross-section can be opened and selected according to the size of the composite sample 1.

[0057] Preferably, a fixing block 5 is provided in the through groove 4, the fixing block 5 corresponds one-to-one with the through groove 4, and a fixing groove 51 for fixing the composite sample 1 is provided on the fixing block 5.

[0058] It should be noted that, in order to meet the testing requirements of composite samples 1 of different sizes or types, this invention includes a fixing block 5 inserted into the through groove 4. The fixing block 5 corresponds one-to-one with the through groove 4, meaning the shape and size of the fixing block 5 are adapted to the through groove 4. Furthermore, a fixing groove 51 for fixing the composite sample 1 is provided on the fixing block 5. The size and shape of the fixing groove 51 can be set and selected according to the specifications of the composite sample 1. That is, different fixing blocks 5 can be replaced when testing composite samples 1 of different sizes or types.

[0059] Specifically, when the cross-section of the through groove 4 is circular, multiple limiting blocks 52 are provided on the fixing block 5, and a groove for fixing the limiting blocks 52 is provided in the through groove 4.

[0060] It should be noted that when the cross-section of the through groove 4 is circular, the outer contour of the fixing block 5 also needs to be set to be circular. Therefore, during the test, the fixing block 5 will rotate relative to the through groove 4. Thus, multiple limiting blocks 52 need to be set on the fixing block 5, and grooves for fixing the limiting blocks 52 are opened in the through groove 4 to better position and prevent rotation.

[0061] Specifically, the distance between the upper block 23 and the lower block 31 is 0.5-1mm.

[0062] It should be noted that in this invention, the cross-sections of the upper block 23 and the lower block 31 are both semi-circular, and the arcuate protrusions of the lower block 31 and the upper block 23 are in opposite directions; moreover, the combined diameter of the upper block 23 and the lower block 31 is equal to the diameters of the upper platform 22 and the lower platform 32. However, during high-temperature testing, the upper and lower clamps 3 will experience thermal expansion and contraction. Therefore, the distance between the upper block 23 and the lower block 31 needs to be controlled within 0.5-1mm to allow for contraction space.

[0063] To more clearly describe this utility model, the following embodiments are provided for further illustration.

[0064] Example 1

[0065] In this embodiment, the composite specimen 1 is made of dissimilar materials. The composite specimen 1 is prepared by welding a first specimen 11 and a second specimen 12 together. Both the first specimen 11 and the second specimen 12 have quadrilateral cross-sections. (Refer to...) Figure 1-2 ;

[0066] Reference Figure 3-4 The fixture in this embodiment includes an upper fixture 2 and a lower fixture 3. The upper fixture 2 includes an upper clamping rod 21, an upper platform 22 and an upper upright block 23 from top to bottom. The upper clamping rod 21 and the upper platform 22 have circular cross-sections, and the upper upright block 23 has a semi-circular cross-section. The outer peripheral surfaces of the upper platform 22 and the upper upright block 23 coincide.

[0067] The lower clamp 3 includes, from top to bottom, a lower upright block 31, a lower platform 32, and a lower clamping rod 33. The lower clamping rod 33 and the lower platform 32 have circular cross-sections, and the lower upright block 31 has a semi-circular cross-section. The outer circumferential surfaces of the lower platform 32 and the lower upright block 31 coincide. The arcuate protrusions of the lower upright block 31 and the upper upright block 23 are in opposite directions. The distance between the upper upright block 23 and the lower upright block 31 is 0.5 mm.

[0068] The upper clamping rod 21, the upper platform 22, and the upper upright block 23 are integrally formed, as are the lower upright block 31, the lower platform 32, and the lower clamping rod 33. The upper clamping rod 21, the upper platform 22, the upper upright block 23, the lower upright block 31, the lower platform 32, and the lower clamping rod 33 are all coaxially arranged, and their axes pass through the composite interface of the composite sample 1; that is, the axes of the upper clamp 2 and the lower clamp 3 coincide with the center line of the composite interface. The upper clamping rod 21 and the lower clamping rod 33 have the same diameter, and the upper platform 22 and the lower platform 32 have the same diameter. The diameter of the upper clamping rod 21 is smaller than the diameter of the upper platform 22, and the diameter of the lower clamping rod 33 is smaller than the diameter of the lower platform 32.

[0069] A through groove 4 is provided on the lower support block 31. The center line of the through groove 4 is parallel to the horizontal plane, and the cross-section of the through groove 4 is square.

[0070] Install the fixture onto the test equipment. The installation process is as follows:

[0071] The upper clamping rod 21 of the upper clamp 2 is clamped onto the upper clamp of the test equipment and locked and fixed. In the vertical direction, the upper clamp 2 consists of the upper clamping rod 21, the upper platform 22 and the upper block 23 from top to bottom.

[0072] Then, the lower clamping rod 33 of the lower clamp 3 is clamped onto the lower clamp of the test equipment and locked in place. In the vertical direction, the lower clamp 3 consists of the lower upright block 31, the lower platform 32 and the lower clamping rod 33 from top to bottom. Then, the first sample 11 in the composite sample 1 is placed in the through groove 4, and the composite interface is flush with the side of the lower upright block 31.

[0073] Testing process:

[0074] During the high-temperature test, the distance between the upper clamp 2 and the lower clamp 3 is adjusted by first adjusting the upper clamp and its lifting mechanism, i.e., until the upper clamp 2 is almost in contact with the composite sample (i.e., the distance between the upper block 23 and the composite sample 1 is 5mm), but it should not come into contact with the sample. After raising the temperature to the specified temperature, the temperature is maintained before compression shearing is performed, and the maximum force is recorded. The shear strength is the maximum force F / interface area.

[0075] Example 2

[0076] The preparation process of Example 2 is largely the same as that of Example 1, except that, according to... Figure 5 In Embodiment 2, a fixing block 5 is provided in the through groove 4. The fixing block 5 corresponds one-to-one with the through groove 4, and a fixing groove 51 for fixing the composite sample 1 is provided on the fixing block 5. When the cross section of the through groove 4 is circular, two symmetrical limiting blocks 52 are provided on the fixing block 5, and a groove for fixing the limiting blocks 52 is provided in the through groove 4.

[0077] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.

Claims

1. A fixture for high-temperature shear strength testing of composite material welding interfaces, characterized in that, The clamp includes an upper clamp (2) and a lower clamp (3). The upper clamp (2) includes, from top to bottom, an upper clamping rod (21), an upper platform (22), and an upper upright block (23). The upper clamping rod (21) and the upper platform (22) have circular cross-sections, and the upper upright block (23) has a semi-circular cross-section. The outer circumferential surfaces of the upper platform (22) and the upper upright block (23) coincide. The lower clamp (3) includes, from top to bottom, a lower upright block (31), a lower platform (32), and a lower clamping rod (33). The lower clamping rod (33) and the lower platform (32) have circular cross-sections, and the lower upright block (31) has a semi-circular cross-section. The outer circumferential surfaces of the lower platform (32) and the lower upright block (31) coincide. The arc-shaped protrusions of the lower upright block (31) and the upper upright block (23) are in opposite directions. A radial through groove (4) is provided on the lower upright block (31).

2. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The upper clamping rod (21), the upper platform (22), the upper upright block (23), the lower upright block (31), the lower platform (32), and the lower clamping rod (33) are all coaxially arranged.

3. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The upper clamping rod (21), the upper platform (22) and the upper upright block (23) are integrally formed, and the lower upright block (31), the lower platform (32) and the lower clamping rod (33) are integrally formed.

4. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The upper clamping rod (21) is connected to the upper platform (22) by a threaded connection; the lower clamping rod (33) is connected to the lower platform (32) by a threaded connection.

5. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The upper clamping rod (21) and the lower clamping rod (33) have the same diameter, and the upper platform (22) and the lower platform (32) have the same diameter.

6. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 5, characterized in that, The diameter of the upper clamping rod (21) is smaller than the diameter of the upper platform (22), and the diameter of the lower clamping rod (33) is smaller than the diameter of the lower platform (32).

7. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The cross-section of the through groove (4) is circular or quadrilateral.

8. The fixture for high-temperature shear strength of composite material welding interfaces according to claim 7, characterized in that, A fixing block (5) is provided in the through groove (4), the fixing block (5) corresponds one-to-one with the through groove (4), and a fixing groove (51) for fixing the composite sample (1) is provided on the fixing block (5).

9. A fixture for high-temperature shear strength of composite material welding interfaces according to claim 7, characterized in that, When the cross-section of the through groove (4) is circular, multiple limiting blocks (52) are provided on the fixing block (5), and a groove for fixing the limiting blocks (52) is provided in the through groove (4).

10. A fixture for high-temperature shear strength of composite material welding interfaces according to claim 1, characterized in that, The distance between the upper block (23) and the lower block (31) is 0.5-1mm.

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