Hopkinson bar three-dimensional fabric composite material dynamic shear test device

Abstract

The invention discloses a Hopkinson bar three-dimensional fabric composite material dynamic shear test device, which relates to the field of three-dimensional fabric composite materials, and comprises an impact shear clamp head, an impact shear clamp end, an incident bar, a transmission bar, an absorption bar, an emission device, a post-processing system and a strain gauge, an impact shearing clamp head is arranged at one end of the incidence rod, an emitting device is arranged at the other end of the incidence rod, the emitting device can horizontally move towards the incidence rod and the impact shearing clamp head in the axis direction, an impact shearing clamp end is arranged at one end of the transmission rod, and an absorption rod is arranged at the other end of the transmission rod. The incident bar and the transmission bar are respectively pasted with a strain gauge, the two strain gauges are connected to the post-processing system, and the post-processing system is used for recording various experimental data. According to the invention, the impact shear strength can be directly measured and the impact shear failure mode can be obtained by assembling and disassembling the impact shear clamp, or the dynamic compression performance can be directly measured and the dynamic compression failure mode can be obtained, and the test data is real and reliable.

Description

Technical Field

[0001] The invention belongs to the field of three-dimensional fabric composite materials, in particular to a Hopkinson rod three-dimensional fabric composite material dynamic shear test device. Background Art

[0002] Three-dimensional fabric structure composite materials have been widely used in aerospace, aviation, protection and civil fields. In this series of engineering applications, impact load is one of the factors that affect the damage of materials. It is necessary to study the mechanical properties of three-dimensional fabric composite materials at different strain rates. At present, the Split Hopkinson Pressure Bar (SHPB) technology is widely used in experimental research on the mechanical behavior characteristics of materials at medium and high strain rates, and is also considered to be one of the most effective methods for measuring the dynamic characteristics of materials.

[0003] Earlier studies on the dynamic mechanical behavior of materials mostly used Hopkinson pressure bars and tension bars as the main equipment, aiming to mainly study the dynamic compression and tension properties of three-dimensional fabric composites at different strain rates, so as to deduce their dynamic shear properties. The process is cumbersome and may cause errors in the results. The impact shear failure test of three-dimensional woven materials was carried out using a modified Hopkinson punching and shearing bar to determine the impact shear failure strength of the material. Due to the special properties of three-dimensional fabric composites, there are great difficulties in their dynamic shear testing. At present, a small number of impact shear tests process the punching and shearing device and the incident rod as a whole, but this method has extremely high requirements for the processing technology. If the test results are not ideal, the entire set of Hopkinson bar devices needs to be remade, which has a long preparation cycle, low flexibility, and high capital cost. Therefore, it is crucial to improve the flexibility and operability of the impact shear test device for three-dimensional fabric composites. Summary of the invention

[0004] The purpose of the present invention is to provide a Hopkinson rod three-dimensional fabric composite material dynamic shear test device to achieve "one rod for two purposes" and flexibly and quickly measure dynamic compression and impact shear failure modes.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a Hopkinson rod three-dimensional fabric composite material dynamic shear test device, a Hopkinson rod three-dimensional fabric composite material dynamic shear test device, characterized in that it includes an impact shear fixture head, an impact shear fixture end, an incident rod, a transmission rod, an absorption rod, a transmitting device, a post-processing system, and a strain gauge, wherein one end of the incident rod is provided with an impact shear fixture head, and the other end is provided with a transmitting device, one end of the transmission rod is provided with an impact shear fixture end, and the other end is provided with an absorption rod, a strain gauge is respectively adhered to the incident rod and the transmission rod, and the two strain gauges are connected to the post-processing system, and the impact shear fixture head, the impact shear fixture end, the incident rod, the transmission rod, and the absorption rod are located on the same axis.

[0006] Furthermore, the impact shearing fixture head includes a first connecting end and a first loading end, wherein the first connecting end is provided with a mounting hole for sleeve-engaging the end of the shooting rod, and the first loading end is a raised shearing head provided at the end of the impact shearing fixture head.

[0007] Furthermore, the end of the impact shearing clamp includes a second connecting end and a second loading end, wherein the second connecting end is provided with a mounting hole for being sleeved on the end of the transmission rod, and the second loading end is a groove provided at the end of the impact shearing clamp.

[0008] Furthermore, a pulse shaper is fixedly connected to the axis of one end of the incident rod and is arranged corresponding to the transmitting device.

[0009] As a further description of the above technical solution: One end of the transmission rod is fixedly connected to the absorption rod, and the absorption rod is correspondingly provided with a buffer device.

[0010] Compared with the prior art, the present invention has the following advantages: BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the implementation structure of the present invention.

[0012] Figure 2 This is a front view of the impact shearing fixture of the present invention.

[0013] Figure 3 It is a schematic diagram of the loading end of the impact shearing fixture head of the present invention.

[0014] Figure 4 It is a schematic diagram of the head connection end of the impact shearing clamp of the present invention.

[0015] Figure 5 It is a schematic diagram of the second loading end of the impact shearing fixture of the present invention.

[0016] Figure 6It is a schematic diagram of the second connection end of the impact shearing clamp of the present invention.

[0017] Among them, there are an impact shearing fixture head 1, an impact shearing fixture end 2, an incident rod 3, a transmission rod 4, an absorption rod 5, a transmitting device 6, a buffer device 7, a post-processing system 8, a strain gauge 9, a pulse shaper 10, a first connecting end 11, a first loading end 12, a second connecting end 21, and a second loading end 22. Implementation

[0018] Reference Figure 1-6 The present invention provides an embodiment: a Hopkinson rod three-dimensional fabric composite material dynamic shear test device, comprising an impact shear fixture head 1, an impact shear fixture end 2, an incident rod 3, a transmission rod 4, an absorption rod 5, a launch device post-processing system 8, and a strain gauge 9; one end of the incident rod 3 is provided with an impact shear fixture head 1, and the other end is provided with a launch device 6, one end of the transmission rod 4 is provided with an impact shear fixture end 2, and the other end is provided with an absorption rod 5, the impact shear fixture head, the impact shear fixture end, the incident rod, the transmission rod, and the absorption rod are located on the same axis, and a strain gauge is respectively adhered to the incident rod and the transmission rod, and the two strain gauges are connected to the post-processing system and used in the Hopkinson rod three-dimensional fabric composite material impact shear test device, so that various data in the Hopkinson rod experiment can be obtained.

[0019] A pulse shaper 10 is also adhered to the other end of the incident rod 3, which can not only fully weaken the dispersion of the stress wave, but also achieve stress balance and constant strain rate deformation of the specimen through proper design.

[0020] The impact shear fixture head 1 includes a first connection end 11 and a first loading end 12. The first connection end 11 is provided with a mounting hole for inserting the end of the injection rod 3. The first loading end 12 is a raised shear head provided at the end of the impact shear fixture head 1. In this way, the impact shear fixture head 1 can be easily disassembled to achieve the impact shear test and the compression rod test respectively.

[0021] When the pressure bar experiment is adopted, there is no need to install an impact shear fixture, and the transmitting device 6, incident bar 3, transmission bar 4, absorption bar 5, buffer device 7, strain gauge 9, and post-processing system 8 required for the Hopkinson pressure bar are directly connected.

[0022] Furthermore, when using the impact shear test, the impact shear fixture head 1 and the impact shear fixture end 2 need to be installed on the device required by the Hopkinson pressure bar. When installing the impact shear fixture, the first connection end 11 must be smooth and flat, and the end face of 11 must be in full contact with the incident rod 3. The second connection end 21 must be smooth and flat, and the end face of 21 must be in full contact with the transmission rod 4. If there is a gap when the first connection end 11 is sleeved on the end of the incident rod 3 and the second connection end 21 is sleeved on the end of the transmission rod 4 and there is a gap and they cannot fit completely, a rubber ring should be installed inside the installation port so that the chuck can be sleeved on the rod and be stable and not fall off.

[0023] Furthermore, the impact shearing clamp end 2 includes a second connecting end 21 and a second loading end 22, wherein the second connecting end 21 is provided with a mounting hole for being sleeved on the end of the transmission rod 4, and the second loading end 22 is a groove provided at the end of the impact shearing clamp end 2.

[0024] Furthermore, the first loading end 12 and the second loading end 22 are clearance-matched to ensure pure shear failure in the Hopkinson bar test. In particular, because the three-dimensional fabric is a flexible material and is easily deformed, the shear fixture is required to have a high precision.

[0025] Furthermore, one end of the transmission rod 4 is fixedly connected to the absorption rod 5, and the absorption rod 5 is correspondingly provided with a buffer device 7, which can absorb most of the impact energy and provide a certain degree of protection for the experimental equipment to increase its service life.

Claims

1. A Hopkinson bar three-dimensional fabric composite material dynamic shear test device, characterized in that: The invention comprises an impact shearing fixture head (1), an impact shearing fixture end (2), an incident rod (3), a transmission rod (4), an absorption rod (5), a transmitting device (6), a post-processing system (8), and a strain gauge (9), wherein An impact shearing fixture head (1) is provided at one end of the incident rod (3), and a launching device (6) is provided at the other end. The launching device (6) moves horizontally along the axis direction toward the incident rod (3). An impact shearing fixture end (2) is provided at one end of the transmission rod (4), and an absorption rod (5) is provided at the other end. The impact shearing fixture head (1) follows the incident rod (3) and moves horizontally along the axis toward the impact shearing fixture end (2). A strain gauge (9) is adhered to each of the incident rod (3) and the transmission rod (4). The two strain gauges (9) are connected to a post-processing system (8). The post-processing system (8) is used to record various experimental data. The impact shearing fixture head (1), the impact shearing fixture end (2), the incident rod (3), the transmission rod (4), and the absorption rod (5) are located on the same axis.

2. The device according to claim 1, characterized in that The impact shearing clamp head (1) comprises a first connecting end (11) and a first loading end (12), wherein The end of the first connection end (11) is provided with a mounting hole for sleeve-fitting onto the end of the shooting rod (3). The first loading end (12) is a protruding shearing head arranged at the end of the impact shearing clamp head (1).

3. The device according to claim 1, characterized in that The impact shearing clamp end (2) comprises a second connecting end (21) and a second loading end (22), wherein The end of the second connection end (21) is provided with a mounting hole for sleeve-connecting to the end of the transmission rod (4). The second loading end (22) is a groove arranged at the end of the impact shearing clamp end (2).

4. The device according to claim 1, characterized in that A pulse shaper (10) is adhered to the axis of one end of the incident rod (3) and is arranged corresponding to the emission device (6).

5. The device according to claim 1, characterized in that One end of the transmission rod (4) is fixedly connected to the absorption rod (5), and the absorption rod (5) is correspondingly provided with a buffer device (7).

Images