CN114812784A - Elastic wave velocity measuring method of Hopkinson bar - Google Patents
Elastic wave velocity measuring method of Hopkinson bar Download PDFInfo
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- CN114812784A CN114812784A CN202210388811.8A CN202210388811A CN114812784A CN 114812784 A CN114812784 A CN 114812784A CN 202210388811 A CN202210388811 A CN 202210388811A CN 114812784 A CN114812784 A CN 114812784A
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- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000012360 testing method Methods 0.000 claims abstract description 37
- 238000005259 measurement Methods 0.000 claims abstract description 27
- 238000009863 impact test Methods 0.000 claims abstract description 4
- 239000002131 composite material Substances 0.000 claims description 30
- 230000000644 propagated effect Effects 0.000 claims description 3
- 229910000838 Al alloy Inorganic materials 0.000 claims description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- 229910000831 Steel Inorganic materials 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 229920000515 polycarbonate Polymers 0.000 claims description 2
- 239000004417 polycarbonate Substances 0.000 claims description 2
- 239000010959 steel Substances 0.000 claims description 2
- 239000010410 layer Substances 0.000 claims 13
- 239000011229 interlayer Substances 0.000 claims 1
- 230000035945 sensitivity Effects 0.000 abstract description 2
- 230000005540 biological transmission Effects 0.000 description 8
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 230000001902 propagating effect Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000004567 concrete Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H5/00—Measuring propagation velocity of ultrasonic, sonic or infrasonic waves, e.g. of pressure waves
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E30/00—Energy generation of nuclear origin
- Y02E30/30—Nuclear fission reactors
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention belongs to the technical field of Hopkinson bar testing, and particularly relates to an elastic wave velocity measuring method of a Hopkinson bar, which comprises the following steps: 1. a test system for measuring elastic wave velocity assembled comprising: the device comprises an emission air gun, a striking rod, an equipment protection device and a laser interference speed measurement system, wherein the emission air gun, the Hopkinson rod, the equipment protection device and the laser interference speed measurement system are sequentially and horizontally arranged. 2. And (3) impact test and data acquisition, wherein a speed signal caused when the elastic wave is transmitted to the free end surface of the tested Hopkinson bar is acquired through a laser interference speed measurement system. 3. And (6) calculating test data. The test system disclosed by the invention is simple in structure, economical and convenient in test system building, short in response time and high in sensitivity of the laser interference speed measurement system, and the laser interference speed measurement system for measuring the elastic wave speed of the Hopkinson bar has the advantages of simplicity and convenience in operation, non-contact property, strong repeatability, high precision and the like.
Description
Technical Field
The invention belongs to the technical field of Hopkinson bar testing, and particularly relates to an elastic wave velocity measuring method of a Hopkinson bar.
Background
In various engineering techniques, military techniques and scientific researches, people usually encounter various impact explosion problems, and for the dynamic impact problems, the strain rate is as high as 10 2 -10 4 s -1 The mechanical response is quite different from that under quasi-static load loading. At present, a Hopkinson bar test system is the most common experimental means for testing dynamic mechanical properties of various materials, including engineering materials such as metal, ceramic, concrete, composite materials and rock, under a high strain rate, and is expanded to the fields of accelerometer sensor calibration and the like.
In the split Hopkinson pressure bar test, strain signals of incident waves are obtained through strain gauges on an incident bar, strain signals of transmitted waves are obtained through strain gauges on a transmitted bar, and the strain signals are connected to a Wheatstone bridge and a subsequent signal amplification and acquisition system for acquisition, so that the stress-strain relationship of the material is measured.
The data calculation and processing formula is as follows:
in the formula: epsilon I 、ε T The strain values of the Hopkinson bar to be detected caused by the incident wave and the transmitted wave are respectively; c B The velocity of the elastic wave of the Hopkinson bar; l S Is the original length of the sample; a. the B 、A S Respectively the sectional area of the Hopkinson bar and the original sectional area of the sample; e B The modulus of elasticity of a hopkinson bar. According to the Hopkinson bar test principle, the strain is a key quantity value to be measured in the test process, and the elastic wave velocity C of the Hopkinson bar to be measured B The method is a constant parameter used for strain calculation, and whether the elastic wave velocity parameter is accurate or not is a key factor influencing the accuracy of a test result.
At present, a method for measuring the elastic wave velocity of a hopkinson rod in a laboratory is to paste two strain gauges at different positions of the measured hopkinson rod, measure the time difference of an elastic wave passing through the two strain gauges, and further calculate the elastic wave velocity. The accuracy of the measuring method depends heavily on the manual pasting precision of the strain gauge, the manual operation error is large, and the measurement repeatability is poor.
Disclosure of Invention
In order to solve the problems of complex operation and large manual operation error of an elastic wave velocity test for measuring the Hopkinson bar through a strain gauge, the invention provides a method for measuring the elastic wave velocity of the Hopkinson bar by using a laser interference velocity measurement system. The technical scheme adopted by the invention is as follows:
an elastic wave velocity measuring method of a Hopkinson bar comprises the following steps:
The test system comprises: launch the gas gun, hit the pole, equipment protection device, laser interference speed measurement system, launch the gas gun, the Hopkinson pole, equipment protection device and laser interference speed measurement system are horizontal arrangement in proper order, the test window that link up around setting up in the equipment protection device, the laser beam that laser interference speed measurement system launched passes the test window and coincides with the pole axis of being surveyed the Hopkinson pole, it sets up in the transmission gas gun to hit the pole activity, the free end face of being surveyed the Hopkinson pole is parallel with equipment protection device and keeps certain clearance.
And 2, impact test and data acquisition.
The transmission drive atmospheric pressure of transmission air gun is adjusted, and the transmission strikes the pole and strikes by survey hopkinson pole, produces the elastic wave of certain amplitude and pulse width at the striking terminal surface of survey hopkinson pole, and the elastic wave propagates backward to the free end face along surveying hopkinson pole. And acquiring a speed signal caused when the elastic wave is transmitted to the free end surface of the tested Hopkinson bar through a laser interference speed measurement system.
And step 3, calculating test data.
Measuring the time point t of the elastic wave transmitted to the free end surface through the speed-time curve of the free end surface of the detected Hopkinson bar acquired in the step 2 1 And a time point t at which the elastic wave is propagated to the free end surface for the second time after being reflected by the striking end surface 2 . Calculating the interval time Δ t ═ t 2 -t 1 Measuring the length L of the Hopkinson bar to be measured B The elastic wave propagation distance in the interval time is 2L B According to the formula
And calculating to obtain the elastic wave velocity of the detected Hopkinson bar. The elastic wave reaches the free end face at t 1 At time t, the light beam is reflected from the free end surface back to the striking end surface and is reflected from the striking end surface back to the free end surface again 2 At that moment, the propagation distance is 2 times the rod length.
The invention has the beneficial effects that:
the test system disclosed by the invention is simple in structure, economical and convenient in test system building, short in response time and high in sensitivity of the laser interference speed measurement system, and the laser interference speed measurement system for measuring the elastic wave speed of the Hopkinson bar has the advantages of simplicity and convenience in operation, non-contact property, strong repeatability, high precision and the like.
Drawings
FIG. 1 is a schematic diagram of the elastic wave velocity measurement method of the present invention;
FIG. 2 is a cross-sectional view of the equipment protection device of the present invention;
FIG. 3 is a free end surface velocity-time curve measured by the laser interference velocity measurement system according to the first embodiment of the present invention;
fig. 4 is a free end surface velocity-time curve measured by the laser interference velocity measurement system according to the second embodiment of the present invention.
In the figure, 1 is a launching gas gun, 2 is a striking rod, 3 is a Hopkinson rod, 4 is a test window, 5 is a composite structure layer I, 6 is a composite structure layer II, 7 is a composite structure layer III, 8 is an equipment protection device base, 9 is a laser interference speed measurement system, and 10 is an equipment protection device.
Detailed Description
The technical solutions related to the present invention are further described below with reference to the drawings and the embodiments, but the technical solutions are not limited thereto.
The first embodiment is as follows:
fig. 1 is a schematic diagram illustrating the principle of the elastic wave velocity measurement method according to the present invention. An elastic wave velocity measuring method of a Hopkinson bar comprises the following steps:
The test system comprises: launch gas gun 1, strike pole 2, equipment protection device 10 and laser interfere system 9 that tests the speed, launch gas gun 1, hopkinson pole 3, equipment protection device 10 and laser interfere system 9 that tests the speed horizontal arrangement in proper order, hopkinson pole 3 is located between launch gas gun 1 and the equipment protection device 10, equipment protection device 10 is located hopkinson pole 3 and laser and interferes between the system 9 that tests the speed, test window 4 that link up around setting up in the equipment protection device 10 is used for making laser beam pass through, laser beam that laser interfered system 9 transmission tested the speed and is coincided with the pole axis of being surveyed hopkinson pole 3, laser beam vertical incidence is at being surveyed hopkinson pole 3's free end face, laser beam diameter is 2 mm. Meanwhile, the equipment protection device 10 is used for absorbing the impact energy of the detected Hopkinson bar 3 and reducing the impact vibration to protect the laser interference speed measurement system 9. The striking rod 2 is movably arranged in the launching air cannon 1, and the striking rod 2 is pushed into the launching air cannon 1 during the test. The free end face of the detected Hopkinson bar 3 is parallel to the equipment protection device 10 and keeps a certain gap, so that the elastic wave is ensured to be secondarily propagated to the free end face of the detected Hopkinson bar 3 without contacting the free end face of the detected Hopkinson bar 3, and the gap between the free end face of the detected Hopkinson bar 3 and the equipment protection device 10 is 2-8 mm, preferably 6 mm. The striking rod 2 and the tested Hopkinson bar 3 are both steel bars, the diameters of the striking rod and the tested Hopkinson bar are both phi 14.5mm, and the average value of the lengths of the tested Hopkinson bars 3 after 5 times of measurement is 1000.7 mm.
Fig. 2 is a cross-sectional view of the device protection apparatus of the present invention. The equipment protection device 10 includes: the device comprises a first composite structure layer 5, a second composite structure layer 6, a third composite structure layer 7 and a device protection device base 8, wherein the first composite structure layer 5, the second composite structure layer 6 and the third composite structure layer 7 are sequentially and fixedly installed on the device protection device base 8, the first composite structure layer 5 is close to the tested Hopkinson bar 3, and a front test window 4 and a rear test window are arranged in the first composite structure layer 5, the second composite structure layer 6 and the third composite structure layer 7 and are communicated with each other. Composite structure layer one 5 be the stereoplasm polycarbonate board that 6mm is thick, composite structure layer two 6 be the aluminum alloy plate that 10mm is thick, composite structure layer three 7 be the soft buffering PU intermediate layer that 56mm is thick, test window 4 be the circular port, the diameter is greater than 2 times the laser beam diameter and be less than surveyed hopkinson pole radius, test window 4 diameter is 4mm ~ 7mm, preferably 5 mm.
The laser interference speed measurement system 9 is prior art, and is not described herein any more, and can be implemented by using a laser interference speed measurement instrument, and the system directly measures a speed signal of the free end face.
And 2, impact test and data acquisition. The transmission drive atmospheric pressure of transmission air gun 1 is adjusted, and transmission striking rod 2 strikes surveyed hopkinson pole 3, produces the elastic wave of certain amplitude and pulse width at surveyed hopkinson pole 3's striking terminal surface, and the elastic wave propagates backward to the free end face along surveyed hopkinson pole 3. Through laser interference velocity measurement system 9, gather the velocity signal that causes when elastic wave propagates to the free end face of surveyed hopkinson pole 3.
And step 3, calculating test data.
Measuring the time point t of the elastic wave propagating to the free end surface through the speed-time curve (namely the end surface moving speed v (t) -t curve) of the free end surface of the detected Hopkinson bar acquired in the step 2 1 And after the elastic wave is reflected by the striking end face, the firstTime point t of secondary propagation to free end face 2 . Calculating the interval time Δ t ═ t 2 -t 1 Length L of measuring target rod B The elastic wave propagation distance in the interval time is 2L B According to the formula
The elastic wave speed of the tested Hopkinson bar is calculated (5180.8 m/s). Fig. 3 shows a velocity-time curve of the free end surface of the hopkinson bar measured by the laser interference velocity measurement system according to the first embodiment of the present invention.
Example two:
the difference between the second embodiment and the first embodiment is:
a copper sheet with the size of phi 7 multiplied by 1mm is placed on the striking end face (namely the front end face) of the tested Hopkinson bar 3 to shape the waveform of the elastic wave. Then, the emission speed of the striking rod 2 is increased, and the amplitude of the elastic wave of the detected Hopkinson bar 3 is increased. Measuring the time point t of the elastic wave propagating to the free end surface through the speed-time curve (namely the end surface moving speed v (t) -t curve) of the free end surface of the tested Hopkinson bar 1 And a time point t when the elastic wave is reflected by the striking end surface and then propagates to the free end surface for the second time 2 . Calculating the interval time Δ t ═ t 2 -t 1 Length L of measuring target rod B The elastic wave propagation distance in the interval time is 2L B According to the formula
The elastic wave speed of the tested Hopkinson bar is calculated (5181.6 m/s). Fig. 4 shows a velocity-time curve of the free end surface of the hopkinson bar measured by the laser interference velocity measurement system according to the second embodiment of the present invention.
Claims (5)
1. An elastic wave velocity measuring method of a Hopkinson bar is characterized by comprising the following steps of:
step 1, assembling a test system for measuring elastic wave velocity;
the test system comprises: the device comprises an emission air gun (1), a striking rod (2), an equipment protection device (10) and a laser interference speed measurement system (9), wherein the emission air gun (1), a Hopkinson rod (3), the equipment protection device (10) and the laser interference speed measurement system (9) are sequentially and horizontally arranged, a test window (4) which is through from front to back is arranged in the equipment protection device (10), a laser beam emitted by the laser interference speed measurement system (9) penetrates through the test window (4) to coincide with the rod axis of the Hopkinson rod (3) to be detected, the striking rod (2) is movably arranged in the emission air gun (1), and the free end face of the Hopkinson rod (3) to be detected is parallel to the equipment protection device (10) and keeps a gap;
step 2, impact test and data acquisition;
adjusting the emission driving air pressure of an emission air gun (1), enabling an emission striking rod (2) to impact a detected Hopkinson rod (3), generating an elastic wave at the striking end face of the detected Hopkinson rod (3), enabling the elastic wave to propagate backwards to a free end face along the detected Hopkinson rod (3), and acquiring a speed signal caused when the elastic wave propagates to the free end face of the detected Hopkinson rod (3) through a laser interference speed measurement system (9);
step 3, test data calculation:
measuring the time point t of the elastic wave transmitted to the free end surface through the speed-time curve of the free end surface of the detected Hopkinson bar (3) acquired in the step 2 1 And a time point t at which the elastic wave is propagated to the free end surface for the second time after being reflected by the striking end surface 2 (ii) a Calculating the interval time Δ t ═ t 2 -t 1 Measuring the length L of the Hopkinson bar (3) to be measured B The elastic wave propagation distance in the interval time is 2L B According to the formula
And calculating to obtain the elastic wave speed of the detected Hopkinson bar (3).
2. The method of measuring the elastic wave velocity of a hopkinson bar according to claim 1, wherein the equipment protection device (10) comprises: composite structure layer one (5), composite structure layer two (6), composite structure layer three (7) and equipment protection device base (8), composite structure layer one (5), composite structure layer two (6) and composite structure layer three (7) are fixed mounting in proper order on equipment protection device base (8) in proper order, composite structure layer one (5) are close to surveyed hopkinson pole (3), set up test window (4) that link up around in composite structure layer one (5), composite structure layer two (6) and the composite structure layer three (7).
3. The method for measuring the elastic wave velocity of the Hopkinson bar according to claim 2, wherein the first composite structure layer (5) is a hard polycarbonate plate, the second composite structure layer (6) is an aluminum alloy plate, the third composite structure layer (7) is a soft buffer PU interlayer, and the test window (4) is a circular hole.
4. The method for measuring the elastic wave velocity of the Hopkinson bar according to claim 1, wherein the striking bar (2) and the Hopkinson bar (3) to be measured are both steel bars.
5. The method for measuring the elastic wave velocity of a Hopkinson bar according to claim 1, wherein a red copper sheet is placed on the striking end face of the Hopkinson bar (3) to be measured.
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| CN202210388811.8A CN114812784B (en) | 2022-04-13 | 2022-04-13 | Elastic wave velocity measuring method of Hopkinson bar |
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5583825A (en) * | 1994-09-02 | 1996-12-10 | Exxon Production Research Company | Method for deriving reservoir lithology and fluid content from pre-stack inversion of seismic data |
| CN1163403A (en) * | 1996-04-22 | 1997-10-29 | 华北工学院 | Impact correction technology for high magnitude accelerometer and its device |
| CN101458263A (en) * | 2009-01-08 | 2009-06-17 | 中北大学 | High-impact acceleration sensor dynamic characteristic tracing calibrating method |
| CN101598619A (en) * | 2009-06-30 | 2009-12-09 | 中北大学 | The calibration steps of pressure sensor acceleration effect and calibrating installation |
| CN102353813A (en) * | 2011-06-12 | 2012-02-15 | 中北大学 | Broadband high range accelerometer frequency response characteristic calibrating device and method thereof |
| CN203616217U (en) * | 2013-12-05 | 2014-05-28 | 张磊 | Experimental device for measuring spall strength of concrete |
| CN104792285A (en) * | 2015-04-02 | 2015-07-22 | 浙江大学 | Online plate thickness measuring system based on laser ultrasonics |
| CN105259373A (en) * | 2015-10-22 | 2016-01-20 | 中国计量科学研究院 | Steel ball launching device and accelerometer dynamic characteristic calibration system comprising same |
| CN106443066A (en) * | 2016-09-23 | 2017-02-22 | 中国航空工业集团公司北京长城计量测试技术研究所 | Laser Doppler vibration measurement method impact acceleration measurement device and method |
| CN107421808A (en) * | 2017-08-21 | 2017-12-01 | 北京交通大学 | A kind of apparatus and method of contactless Hopkinson pressure bar measurement |
| CN110672878A (en) * | 2019-10-10 | 2020-01-10 | 华东光电集成器件研究所 | Triaxial high-range acceleration sensor lateral sensitivity ratio testing device |
| CN211602143U (en) * | 2020-03-09 | 2020-09-29 | 西南交通大学 | Low-temperature target device for impact test of non-solid opaque sample |
-
2022
- 2022-04-13 CN CN202210388811.8A patent/CN114812784B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5583825A (en) * | 1994-09-02 | 1996-12-10 | Exxon Production Research Company | Method for deriving reservoir lithology and fluid content from pre-stack inversion of seismic data |
| CN1163403A (en) * | 1996-04-22 | 1997-10-29 | 华北工学院 | Impact correction technology for high magnitude accelerometer and its device |
| CN101458263A (en) * | 2009-01-08 | 2009-06-17 | 中北大学 | High-impact acceleration sensor dynamic characteristic tracing calibrating method |
| CN101598619A (en) * | 2009-06-30 | 2009-12-09 | 中北大学 | The calibration steps of pressure sensor acceleration effect and calibrating installation |
| CN102353813A (en) * | 2011-06-12 | 2012-02-15 | 中北大学 | Broadband high range accelerometer frequency response characteristic calibrating device and method thereof |
| CN203616217U (en) * | 2013-12-05 | 2014-05-28 | 张磊 | Experimental device for measuring spall strength of concrete |
| CN104792285A (en) * | 2015-04-02 | 2015-07-22 | 浙江大学 | Online plate thickness measuring system based on laser ultrasonics |
| CN105259373A (en) * | 2015-10-22 | 2016-01-20 | 中国计量科学研究院 | Steel ball launching device and accelerometer dynamic characteristic calibration system comprising same |
| CN106443066A (en) * | 2016-09-23 | 2017-02-22 | 中国航空工业集团公司北京长城计量测试技术研究所 | Laser Doppler vibration measurement method impact acceleration measurement device and method |
| CN107421808A (en) * | 2017-08-21 | 2017-12-01 | 北京交通大学 | A kind of apparatus and method of contactless Hopkinson pressure bar measurement |
| CN110672878A (en) * | 2019-10-10 | 2020-01-10 | 华东光电集成器件研究所 | Triaxial high-range acceleration sensor lateral sensitivity ratio testing device |
| CN211602143U (en) * | 2020-03-09 | 2020-09-29 | 西南交通大学 | Low-temperature target device for impact test of non-solid opaque sample |
Non-Patent Citations (2)
| Title |
|---|
| ZHAOXIN YANG 等: "Dynamic characterization method of accelerometers based on the Hopkinson bar calibration system", SENSORS AND ACTUATORS A: PHYSICAL, 1 July 2019 (2019-07-01), pages 21 - 28 * |
| 李庆丰 等: "激励脉冲宽度对加速度计冲击校准误差的影响", 仪表技术与传感器, no. 1, 15 October 2009 (2009-10-15), pages 44 - 46 * |
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