Tensile strength testing tool for ceramic-based composite bolt

Abstract

The utility model discloses a tensile strength testing tool for a ceramic-based composite bolt, relates to the technical field of fastener testing, and can solve the problem of tensile testing of the ceramic-based composite bolt. The tensile strength testing tool for the ceramic-based composite bolt comprises an upper clamp and a lower clamp which are respectively used for mounting two ends of the ceramic-based composite bolt, and a driving mechanism for driving the upper clamp and the lower clamp, the device further comprises a load transmission assembly rotationally connected to the upper clamp or the lower clamp, and the load transmission assembly is provided with an inner threaded hole used for installing a ceramic-based composite bolt.

Description

Technical Field

[0001] This utility model relates to the field of fastener testing technology, specifically to a tensile strength testing fixture for ceramic-based composite bolts. Background Technology

[0002] Currently, ceramic matrix composites are advanced materials with high-temperature strength, high oxidation resistance, low density, and excellent fatigue resistance, and are widely used in aerospace, energy, and automotive fields. However, due to their inherent brittleness and complex microstructure, tensile strength testing of bolts or other fasteners made of ceramic matrix composites faces numerous technical challenges. While ceramic matrix composite bolts can provide reliable connections under extreme conditions due to their high strength and high modulus, their brittle fracture characteristics, anisotropy, and high processing difficulty make it difficult to directly apply traditional testing methods for metal bolts.

[0003] During testing, the mechanical properties of ceramic matrix composites are significantly affected by stress concentration, assembly processes, and environmental factors. Therefore, the testing methods need to be specially designed to ensure the accuracy and reliability of the results. The key to tensile strength testing is applying a uniform axial load to the sample and avoiding localized stress concentration or premature material failure caused by improper clamping or tooling design. Furthermore, the complex microstructure of ceramic matrix composites leads to high dispersion in test data, making the design of the testing fixture particularly important. An ideal fixture should be able to achieve precise load transfer without damaging the sample, while also accommodating the material's high hardness and brittleness, preventing fracture caused by excessive or uneven clamping forces.

[0004] Existing testing methods for metal bolts cannot fully meet the special requirements of ceramic matrix composites, and the design of traditional fixtures may affect the test results due to stress concentration on the sample surface. Utility Model Content

[0005] The purpose of this application is to provide a tensile strength testing fixture for ceramic matrix composite bolts, thereby solving the problem of tensile testing of ceramic matrix composite bolts.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following solution:

[0007] This application provides a tensile strength testing fixture for ceramic matrix composite bolts, including an upper clamp and a lower clamp for mounting the two ends of the ceramic matrix composite bolt, and a driving mechanism for driving the upper clamp and the lower clamp.

[0008] It also includes a load transfer assembly rotatably connected to the upper or lower clamp, the load transfer assembly having an internal threaded hole for mounting ceramic-based composite bolts.

[0009] Optionally, the driving mechanism is a linear driving mechanism;

[0010] A movable seat is provided on the output shaft of the linear drive mechanism;

[0011] A first mounting rod is provided on the linear drive mechanism, and a second mounting rod is provided on the movable seat. The first and second mounting rods are arranged parallel to each other, and the lower clamp and the upper clamp are respectively installed on the first and second mounting rods.

[0012] The first mounting rod is located directly below the second mounting rod.

[0013] Optionally, the linear drive mechanism is a hydraulically driven linear drive mechanism.

[0014] Optionally, the lower clamp is provided with a lower mounting hole, and the upper clamp is provided with an upper mounting hole;

[0015] The first mounting rod is inserted into the upper mounting hole and detachably connected to it;

[0016] The second mounting rod is inserted into the lower mounting hole and detachably connected to it.

[0017] Optionally, the lower clamp is provided with a lower mounting groove at the top, and the load transfer component is rotatably connected to the lower mounting groove of the lower clamp;

[0018] The load transfer assembly includes a horizontally arranged through rod and a bolt fixing sleeve. The through rod passes through the bottom of the bolt fixing sleeve and the lower mounting groove and can slide freely within the bolt fixing sleeve. The load transfer assembly is rotatably connected to the lower clamp through the through rod.

[0019] The internal threaded hole is located inside the bolt fixing sleeve.

[0020] Optionally, the insertion rod and the first mounting rod are arranged perpendicular to each other.

[0021] Optionally, the bottom of the upper clamp is provided with an upper mounting groove, and bolt head support plates extend inward from both sides of the bottom of the upper mounting groove.

[0022] Optionally, the free ends of the bolt head support plates extending inward are each provided with washer mounting steps for installing elastic washers;

[0023] It also includes an elastic gasket for placement on the gasket mounting step, the thickness of which is equal to the height of the gasket mounting step.

[0024] Optionally, the elastic gasket is a rubber-metal composite gasket.

[0025] Compared with the prior art, this application has the following beneficial effects:

[0026] 1. By using a separate design for the upper and lower clamps and setting up load transfer components and elastic washers, the bolt to be tested can be installed on the tensile strength testing fixture disclosed in this application. This avoids the problem that the bolt to be tested is brittle and has local stress concentration due to the characteristics of ceramic matrix composites, which can cause premature non-real fracture during the test and result in inaccurate test results.

[0027] Second, by designing the position and direction of the first mounting rod, the second mounting rod, and the through rod, the axis of the bolt to be tested can be parallel to the direction of movement of the movable seat after installation, ensuring that the force on the bolt to be tested is consistent with its axis, and ensuring the accuracy of the tensile test results of the bolt to be tested.

[0028] Third, by detachably mounting the lower clamp and the upper clamp onto the first mounting rod and the second mounting rod respectively, the lower clamp and the upper clamp can be detached and replaced, making maintenance easy.

[0029] Fourth, the load transfer component is detachably and rotatably connected to the lower fixture via a through rod, which allows this application to adapt to various types of bolts under test by replacing different types of load transfer components, thereby reducing the testing cost of different types of bolts under test. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an embodiment of this application.

[0031] Figure 2 This is a schematic diagram of the structure during tensile testing according to an embodiment of this application.

[0032] Explanation of reference numerals in the attached drawings: 11-Linear drive mechanism, 111-First mounting rod, 12-Oil inlet pipe, 13-Oil outlet pipe, 14-Modible seat, 141-Second mounting rod, 2-Upper clamp, 21-Upper mounting groove, 211-Bolt head support plate, 212-Washer mounting step, 22-Upper mounting hole, 3-Lower clamp, 31-Lower mounting groove, 32-Lower mounting hole, 4-Load transfer assembly, 41-Through rod, 42-Bolt fixing sleeve, 421-Internal threaded hole, 5-Elastic washer, 6-Bolt to be tested. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0034] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inner", "outer", "front", "rear", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0035] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set up," "have," "install," "connect," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0036] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0037] like Figure 1 and Figure 2 As shown, this embodiment provides a tensile strength testing fixture for ceramic-based composite bolts, including an upper clamp 2 and a lower clamp 3 for mounting the two ends of the ceramic-based composite bolt, and a driving mechanism for driving the upper clamp 2 and the lower clamp 3.

[0038] It also includes a load transfer assembly 4 rotatably connected to the upper clamp 2 or the lower clamp 3, the load transfer assembly 4 being provided with an internal threaded hole 421 for installing ceramic-based composite bolts.

[0039] This embodiment uses a separate design of upper clamp 2 and lower clamp 3, and sets up a load transfer component 4 and an elastic gasket 5. This allows the bolt to be tested 6 to be installed on the tensile strength testing fixture disclosed in this application. This avoids the problem that the bolt to be tested 6 is brittle and has local stress concentration due to the characteristics of ceramic matrix composites, which would cause the bolt to be tested 6 to fracture prematurely during the test and the test results to be inaccurate.

[0040] Specifically, in this embodiment, the driving mechanism is a linear driving mechanism 11;

[0041] A movable seat 14 is provided on the output shaft of the linear drive mechanism 11;

[0042] A first mounting rod 111 is provided on the linear drive mechanism 11, and a second mounting rod 141 is provided on the movable seat 14. The first mounting rod 111 and the second mounting rod 141 are arranged parallel to each other. The lower clamp 3 and the upper clamp 2 are respectively installed on the first mounting rod 111 and the second mounting rod 141.

[0043] The first mounting rod 111 is located directly below the second mounting rod 141 to prevent the bolt's force direction from being non-parallel to its axis.

[0044] Specifically, in this embodiment, the linear drive mechanism 11 is a hydraulically driven linear drive mechanism 11. Technicians can replace it with an electrically driven or pneumatically driven linear drive mechanism 11 as needed. No specific examples are given here.

[0045] In this embodiment, as Figure 1 As shown, the linear drive mechanism 11 is also equipped with an oil inlet pipe 12, an oil outlet pipe 13, a piston (not shown in the figure), a hydraulic oil chamber (not shown in the figure), and other structures. The hydraulic drive mechanism is a hydraulic cylinder, which is a common mechanical mechanism and will not be described in detail here. In this embodiment, the hydraulic drive mechanism 11 is used to ensure that there is sufficient driving force when the upper clamp 2 and the lower clamp 3 are far apart from each other, and at the same time, it is convenient for data monitoring.

[0046] Specifically, in this embodiment, the lower clamp 3 is provided with a lower mounting hole 32, and the upper clamp 2 is provided with an upper mounting hole 22;

[0047] The first mounting rod 111 is inserted into the upper mounting hole 22 and is detachably connected to it;

[0048] The second mounting rod 141 is inserted into the lower mounting hole 32 and is detachably connected to it.

[0049] In this embodiment, by detachably mounting the lower clamp 3 and the upper clamp 2 onto the first mounting rod 111 and the second mounting rod 141 respectively, the lower clamp 3 and the upper clamp 2 can be detached and replaced, making maintenance easy.

[0050] Specifically, in this embodiment, the lower clamp 3 is provided with a lower mounting groove 31 at its top, and the load transfer component 4 is rotatably connected to the lower mounting groove 31 of the lower clamp 3.

[0051] The load transfer assembly 4 includes a horizontally arranged through rod 41 and a bolt fixing sleeve 42. The through rod 41 passes through the bolt fixing sleeve 42 and the bottom of the lower mounting groove 31 and can slide freely in the bolt fixing sleeve 42. The load transfer assembly 4 is rotatably connected to the lower clamp 3 through the through rod 41.

[0052] The internal threaded hole 421 is provided inside the bolt fixing sleeve 42.

[0053] In this embodiment, the load transfer component 4 is detachably rotatably connected to the lower clamp 3 via the insertion rod 41, which allows the present application to adapt to various types of test bolts 6 by replacing different types of load transfer components 4, thereby reducing the testing cost of different types of test bolts 6.

[0054] Specifically, in this embodiment, the insertion rod 41 and the first mounting rod 111 are arranged perpendicular to each other, which facilitates the adjustment of the state of the bolt 6 to be tested and avoids the problem that the axis of the bolt 6 to be tested is not parallel to its force direction, which would lead to inaccurate tensile strength test results of the bolt 6 to be tested.

[0055] Specifically, in this embodiment, the bottom of the upper clamp 2 is provided with an upper mounting groove 21, and bolt head support plates 211 extend inward on both sides of the bottom of the upper mounting groove 21 to facilitate supporting the bolt head of the bolt 6 to be tested.

[0056] Specifically, in this embodiment, the free ends of the bolt head support plate 211 extending inward are all provided with washer mounting steps 212 for installing elastic washers 5;

[0057] It also includes an elastic washer 5 for placement on the washer mounting step 212. The thickness of the elastic washer 5 is equal to the height of the washer mounting step 212. Setting the elastic washer 5 can prevent the head of the bolt 6 to be tested from having excessive local stress concentration.

[0058] Specifically, in this embodiment, the elastic gasket 5 is a rubber-metal composite gasket. The rubber-metal composite gasket in this embodiment is a common mechanical part, which will not be described in detail here.

[0059] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of this utility model, and the utility model is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of this utility model, and these modifications and improvements are also considered to be within the protection scope of this utility model.

Claims

1. A tensile strength testing fixture for ceramic-based composite bolts, characterized in that, The device comprises an upper clamp (2) and a lower clamp (3) for mounting the bolt of the ceramic matrix composite respectively, and a driving mechanism for driving the upper clamp (2) and the lower clamp (3); The device further comprises a load transmission assembly (4) rotatably connected to the upper clamp (2) or the lower clamp (3), and the load transmission assembly (4) is provided with an internally threaded hole (421) for mounting the bolt of the ceramic matrix composite.

2. The tensile strength test tool for a ceramic matrix composite bolt according to claim 1, wherein The driving mechanism is a linear driving mechanism (11). The output shaft of the linear driving mechanism (11) is provided with a movable seat (14). The linear driving mechanism (11) is provided with a first mounting rod (111), and the movable seat (14) is provided with a second mounting rod (141), the first mounting rod (111) and the second mounting rod (141) are arranged in parallel with each other, and the lower clamp (3) and the upper clamp (2) are mounted on the first mounting rod (111) and the second mounting rod (141) respectively. The first mounting rod (111) is located directly below the second mounting rod (141).

3. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 2, wherein The linear driving mechanism (11) is a linear driving mechanism (11) driven by hydraulic pressure.

4. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 2, wherein The lower clamp (3) is provided with a lower mounting hole (32), and the upper clamp (2) is provided with an upper mounting hole (22). The first mounting rod (111) is inserted into the upper mounting hole (22) and detachably connected thereto. The second mounting rod (141) is inserted into the lower mounting hole (32) and detachably connected thereto.

5. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 1, wherein The lower clamp (3) is provided with a lower mounting groove (31) at the top, and the load transmission assembly (4) is rotatably connected to the lower mounting groove (31) of the lower clamp (3). The load transmission assembly (4) comprises a horizontally arranged penetrating rod (41) and a bolt fixing sleeve (42), the penetrating rod (41) penetrates through the bolt fixing sleeve (42) and the bottom of the lower mounting groove (31) and is freely slidable in the bolt fixing sleeve (42), and the load transmission assembly (4) is rotatably connected to the lower clamp (3) through the penetrating rod (41). The internally threaded hole (421) is arranged in the bolt fixing sleeve (42).

6. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 5, wherein The penetrating rod (41) is arranged perpendicularly to the first mounting rod (111).

7. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 1, wherein The bottom of the upper clamp (2) is provided with an upper mounting groove (21), and both sides of the bottom of the upper mounting groove (21) extend inwardly to form a bolt head supporting plate (211).

8. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 7, wherein The free ends of the inwardly extending bolt head supporting plates (211) are provided with a gasket mounting step (212) for mounting an elastic gasket (5). The device further comprises an elastic gasket (5) placed on the gasket mounting step (212), and the thickness of the elastic gasket (5) is equal to the height of the gasket mounting step (212).

9. The tensile strength testing tool for a ceramic matrix composite bolt according to claim 8, wherein The elastic gasket (5) is a rubber-metal composite gasket.

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