Explosive impact shear sensitivity tester with controllable temperature and loading pulse width

Abstract

The application discloses an explosive impact and shear sensitivity tester with adjustable temperature and loading pulse width, which comprises a main loading part, a charge sample cabin part, a temperature control part and a testing part, and is fixed on an I-beam as a whole structure; the height of each part is adjusted to ensure coaxiality in the loading direction; the loading mode is pneumatic loading; a bullet rod is pressurized and released by a high-pressure air pump to load the sample to be tested. In order to retain the low-amplitude and long-pulse loading condition of the SHPB, improve the energy deposition rate, and consider the influence of the charge structure constraint, the explosive impact and shear sensitivity tester designed in the application can change the loading pulse width, amplitude and controllable temperature, the components have good replaceability, the explosive sensitivity test at different temperatures can be realized through the temperature control device, and various information can be extracted and analyzed through various external measuring instruments.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of explosive impact and shear sensitivity test, and particularly relates to an explosive impact and shear sensitivity tester with controllable temperature and loading pulse width. BACKGROUND

[0002] Sensitivity is one of the key performances of whether the explosive can be used, and is a standard of safety and reliability of the explosive. The mechanical sensitivity of the explosive refers to the difficulty degree of causing the explosion of the explosive under the mechanical action. According to different external stimulation conditions, the ignition and initiation caused by the mechanical stimulation is generally divided into impact ignition with high load amplitude and short pulse width and non-impact ignition with low amplitude and long pulse width. The mechanism of causing the non-impact ignition mainly includes impact, friction, shear and the like.

[0003] It is a commonly used method to evaluate the impact safety of the explosive by using the drop hammer test. The traditional explosive impact sensitivity test usually adopts the drop hammer test, and if the burst sound is detected after the collision, it is considered to be ignited. However, the standard drop hammer test only uses the gravitational acceleration loading, so the loading speed generated thereby is limited. Secondly, although the loading load can be measured by using the force measuring device in the drop hammer test, the loss of the drop hammer kinetic energy also includes the energy required for the deformation of the weight, the hammer and the anvil, so that the energy deposited in the sample is not accurate. Overall, the drop hammer test measures a single parameter, and lacks the necessary conditions for judging the impact ignition of the explosive.

[0004] The explosive drop hammer standard test in China mainly uses the explosion probability P or the characteristic drop height H50 to evaluate the impact sensitivity of the explosive. The explosion probability method is that a drop hammer with a certain mass freely falls from a fixed height, and the explosion and non-explosion of the explosive are observed, 25 tests are performed, and the probability P of the explosion of the explosive is obtained. The characteristic drop height method is that a drop hammer with a certain mass is adjusted by adjusting the drop height to perform multiple tests, and the drop height H50 of the drop hammer when the 50% explosion probability of the explosive occurs is obtained. The standard amount of the explosive to be tested during the test is 50 mg, and the shape is usually powder or scattered powder particles. Both the amount and the shape are quite different from the actual charge, and the test only focuses on the "non-one or zero" explosion and non-explosion, which is not enough for the in-depth study of the ignition mechanism of the explosive. Therefore, researchers in various countries improve the traditional drop hammer test device or establish a new test method to more carefully study the non-impact ignition of the explosive.

[0005] In addition, with the maturation of characterization and detection technology, in the test process, in addition to the direct observation of scanning electron microscope, high-speed photography, ultrasonic, infrared camera scanning, nuclear magnetic resonance, X-ray and the like, the damage change can also be obtained by indirect measurement, and the ignition process of the explosive during the test process.

[0006] The pulse condition generated by the bullet rod impact in the SHPB test device is similar to the non-impact load (low amplitude, long pulse) condition of the explosive, but due to the existence of the transmission rod, the energy of the incident wave is dissipated to a certain extent and cannot be completely deposited in the PBX, so even if a more sensitive explosive sample is used, the SHPB test rarely ignites.

[0007] As one of the main dynamic load test technologies, the SHPB technology is widely used in the research on the mechanical properties and responses of materials under high strain rates. However, the PBX can only be successfully ignited under very high strain rates. Considering the softness of the matching rod due to impedance effect, the rod will deform greatly under this strain rate, and the stress-strain information of the material obtained through the strain signals of the incident rod and the transmission rod is not accurate, making it difficult to calculate the energy and energy rate that lead to successful ignition.

[0008] In the SHPB-anvil test, the bullet rod is limited, and the strain in the incident rod is not measured. Moreover, the test mainly measures the impact sensitivity of bare explosives, and cannot obtain the impact / shear response process of the explosive charge under the constraint of the shell. At the same time, the dynamic shear punching test and the SHPB-anvil test do not realize the test of the sensitivity of the charge at different temperatures. SUMMARY

[0009] The purpose of the present application is to provide a temperature and loading pulse width adjustable explosive impact and shear sensitivity tester to solve the problems existing in the prior art. Different initial loading modes are obtained by replacing the launch bullet rod (flying piece), the loading speed is changed by adjusting the launch air pressure, and the explosive sensitivity under impact / shear is obtained by replacing the sample cabin. The device has good mobility, flexible disassembly and assembly structure, the sample cabin is installed on the anvil bottom with protection, the assembly and disassembly of parts are convenient, and if damaged, the related parts can be replaced.

[0010] To achieve the above purpose, the present application provides the following scheme: the present application provides a temperature and loading pulse width adjustable explosive impact and shear sensitivity tester, comprising

[0011] The main loading part fixed on the I-beam comprises a gas cylinder, a launch tube, a bullet rod and an incident rod. A plurality of support bases are sequentially arranged on the I-beam along the impact direction of the incident rod. The coaxially arranged launch tube, bullet rod and incident rod are sequentially and movably arranged in the support bases from right to left. The gas cylinder is used to provide pressure for the inner cavity of the launch tube. The first end of the bullet rod is arranged in the inner cavity of the launch tube. The second end of the bullet rod is used to impact the first end of the incident rod. The second end of the incident rod is used to impact the sample; and

[0012] The charge sample cabin part comprises an anvil body, a sleeve and a striking column, the anvil body is fixed on the I-beam, a groove is formed on the anvil body at a position corresponding to the second end of the incident rod, the sleeve is assembled in the groove, the bottom of the sleeve is provided with the striking column, and the striking column and the inner cavity of the sleeve form a sample cabin, and the sample is placed in the sample cabin.

[0013] The temperature control part comprises a heating sheet, a thermocouple and a temperature control device, the heating sheet and the thermocouple are connected with the temperature control device, the heating sheet is used for heating the sample, and the thermocouple is used for measuring the temperature of the sample and the temperature of the heating sheet.

[0014] The test part comprises a pressure measuring unit, an incident stress and strain measuring unit, a bullet speed measuring unit and a photography unit, the pressure measuring unit is used for measuring the impact pressure of the sample, the incident stress and strain measuring unit is used for measuring the strain rate and stress of the sample, the bullet speed measuring unit is used for measuring the impact speed of the bullet rod, and the photography unit is used for recording the test process.

[0015] Preferably, the whole temperature and loading pulse width adjustable explosive impact shear sensitivity tester is placed in a protective box, and the internal reaction is observed through the tempered glass on one side of the protective box.

[0016] Preferably, the inner diameter of the sleeve is greater than the outer diameter of the incident rod, and the side surface of the sleeve is provided with a pressure relief hole.

[0017] Preferably, the striking column is made of an elastic body material, and the elastic modulus of the striking column is 2-3 orders of magnitude higher than that of the explosive.

[0018] Preferably, the heating sheet is a ceramic heating sheet, the thermocouple at the center of the heating sheet is in contact with the sample and collects the temperature data of the sample in the heating process, the thermocouples at the edges of the heating sheet are used for measuring the temperature of the heating sheet and transmitting the temperature data to the external temperature control device, and the temperature control device adjusts the temperature rising rate of the heating sheet by adjusting the current size.

[0019] Preferably, compressed air is injected into the gas cylinder through an air compressor, a pneumatic valve is arranged at the gas outlet of the gas cylinder, the pneumatic valve is controlled manually, a pressure gauge is further arranged above the gas cylinder, and the pressure gauge is used for displaying the internal pressure of the gas cylinder; the gas cylinder is inflated to the required pressure according to the required impact speed.

[0020] Preferably, the bullet rod impacts the incident rod at different speeds, forming a square wave pulse with a pulse width of 2l / c0 that propagates along the incident rod, where l is the length of the bullet rod and c0 is the impact speed of the bullet rod; the impact speed of the bullet rod determines the amplitude of the pulse, and different pulse width loading stress waves are obtained by replacing bullet rods of different lengths.

[0021] Preferably, the pressure measuring unit includes a PVDF thin-film piezoelectric sensor, the PVDF thin-film piezoelectric sensor is mounted on the striking post, the PVDF thin-film piezoelectric sensor and the striking post are bonded to the chassis, and the chassis is detachably placed in the groove.

[0022] Preferably, the incident stress and strain measurement unit is a strain gauge mounted on the incident rod, and the strain gauge on the incident rod is used to collect the incident wave ε. i and reflected wave ε r The strain rate and stress of the specimen are solved by using reflected and incident waves.

[0023] Preferably, the bullet velocity measuring unit includes a laser velocimeter, which is installed at the outlet of the firing tube. The impact velocity of the bullet rod is calculated by the time it takes for the bullet rod to pass between two adjacent laser beams.

[0024] The present invention achieves the following beneficial technical effects compared to the prior art:

[0025] This invention provides an explosive impact / shear sensitivity testing instrument with adjustable temperature and loading pulse width. It includes a main loading section, a sample chamber, a temperature control section, and a testing section. The overall structure is fixed to an I-beam. The height of each part is adjusted to ensure coaxiality in the loading direction. The loading method is pneumatic loading, using a high-pressure air pump to pressurize and release the bullet rod to load the sample under test. To retain the low amplitude, long pulse loading conditions of SHPB (Short Scale Point Pressure) and improve the energy deposition rate, while considering the influence of the charge structure constraints, this invention designs an explosive impact / shear sensitivity testing device that can change the loading pulse width, amplitude, and controllable temperature. Its components have good replaceability, and explosive sensitivity tests at different temperatures can be achieved through a temperature control device. Various information can be extracted and analyzed through multiple external measuring instruments. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1A schematic diagram of the overall structure of an explosive impact shear sensitivity tester with adjustable temperature and loading pulse width;

[0028] Figure 2 Structural composition diagram of the propellant loading test chamber;

[0029] Figure 3 This is a structural diagram of the temperature control section;

[0030] Figure 4 This is a schematic diagram of the installation of a PVDF thin-film piezoelectric sensor.

[0031] Figure 5 This is a schematic diagram of a PVDF piezoelectric sensor measurement.

[0032] The components include: 1. Anvil; 2. Sample chamber; 3. Temperature control unit; 4. Incident rod; 5. Laser velocimeter; 6. Support base; 7. Bullet rod; 8. Launch tube; 9. Pressure gauge; 10. Pneumatic valve; 11. Gas cylinder; 12. I-beam; 13. Bottom base; 14. Sleeve; 15. Sample; 16. Pressure relief hole; 17. Impact pin; 18. High-temperature ceramic heating element; 19. Thermocouple; 20. Temperature control device; 21. Chassis; 22. PVDF thin-film piezoelectric sensor. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] The purpose of this invention is to provide an explosive impact / shear sensitivity testing instrument with adjustable temperature and loading pulse width to solve the problems existing in the prior art. Different initial loading modes can be obtained by changing the launching bullet rod (flying plate), the loading speed can be changed by adjusting the launching gas pressure, and the explosive sensitivity under impact / shear action can be obtained by changing the sample chamber. The equipment has good mobility and flexible disassembly and assembly. The sample chamber is installed on a protective anvil, and the assembly and disassembly of the parts are convenient. If any parts are damaged, the relevant parts can be replaced.

[0035] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] like Figures 1-5 As shown, the present invention provides an explosive impact-shear sensitivity testing instrument with adjustable temperature and loading pulse width, including...

[0037] The main loading section, fixed to the I-beam 12, includes a gas cylinder 11, a launching tube 8, a projectile rod 7, and an incident rod 4. Multiple support bases 6 are sequentially arranged on the I-beam 12 along the impact direction of the incident rod 4. The launching tube 8, projectile rod 7, and incident rod 4, arranged coaxially, are sequentially and movably positioned within the support bases 6 from right to left. The gas cylinder 11 provides pressure to the inner cavity of the launching tube 8. The first end of the projectile rod 7 passes through the inner cavity of the launching tube 8, and the second end of the projectile rod 7 impacts the first end of the incident rod 4. The second end of the incident rod 4 impacts the sample 15.

[0038] The sample chamber 15 includes an anvil 1, a sleeve 14, and an impact pin 17. The anvil 1 is fixed to the I-beam 12. A groove is formed on the anvil 1 at a position corresponding to the second end of the incident rod 4. The sleeve 14 is fitted into the groove, and the impact pin 17 is provided at the bottom of the sleeve 14. The sample chamber 15 is formed between the impact pin 17 and the inner cavity of the sleeve 14, and the sample 15 is placed in the sample chamber 15.

[0039] Temperature control section 3 includes a heating element, a thermocouple 19, and a temperature control device 20. Both the heating element and the thermocouple 19 are connected to the temperature control device 20. The heating element is used to heat the sample 15, and the thermocouple 19 is used to measure the temperature of the sample 15 and the temperature of the heating element.

[0040] The testing section includes a pressure measurement unit, an incident stress and strain measurement unit, a bullet velocity measurement unit, and a photography unit. The pressure measurement unit is used to measure the impact pressure on the specimen 15, the incident stress and strain measurement unit is used to measure the strain rate and stress of the specimen 15, the bullet velocity measurement unit is used to measure the impact velocity of the bullet rod 7, and the photography unit is used to record the test process.

[0041] To integrate explosive impact sensitivity testing and impact-shear sensitivity testing, the testing instrument is divided into a main loading section and a sample chamber. For studying the mechanical sensitivity of the explosive, considering the need to prevent significant deformation during high-speed loading and the potential hazards after ignition, the main body is made of alloy steel, with the overall structure fixed to an I-beam 12. Multiple bases 13 are provided at the bottom of the I-beam 12, and the height of each part is adjusted to ensure coaxiality in the loading direction. Some parts (sleeve 14, anvil, etc.) are made of high-strength hardened steel. The loading method is pneumatic loading, using a high-pressure air pump to pressurize and release the bullet rod 7 to load the sample under test.

[0042] like Figures 1-2As shown, in one embodiment, to constrain the impact sensitivity of the explosive charge, the inner diameter of the sleeve 14 is slightly larger than the diameter of the incident rod 4, so that the loading process is not affected by sidewall friction. The sleeve 14 has a pressure relief hole 16 on its side for rapid pressure relief during explosive ignition, and is equipped with an impact pin 17. The impact pin 17 is made of a high-strength elastomer, whose elastic modulus is 2-3 orders of magnitude higher than that of the explosive. Therefore, the response stress measured by the sensor can be treated as the impact loading and response stress of the explosive charge.

[0043] In one embodiment, to ensure the safety of the test process, the entire temperature and loading pulse width adjustable explosive impact shear sensitivity tester is placed inside a protective box, and the internal reaction is observed through tempered glass on one side of the protective box.

[0044] In one embodiment, the choice of heater is greatly limited in order to balance heating effect and sample installation conditions. Traditional heating coils composed of resistance wires are not suitable in this device. The selection of sample chamber 2 and the installation method will limit the shape and heating effect of the heater. The assembly of the heating coil and the heated device is also a difficult problem to solve.

[0045] In summary, the temperature-controlled heating system comprises a high-temperature ceramic heating element 18, a thermocouple 19, and an external temperature control device 20. The high-temperature ceramic heating element 18 converts electrical energy into heat energy, comes into contact with the sample 15, and conducts heat to the sample 15. The thermocouple 19 at the center of the heating element contacts the sample 15 and collects the temperature data of the sample 15 during the heating process. Thermocouples 19 at the edge of the heating element measure the temperature of the heating element and transmit the temperature data to the external temperature control device 20. Upon receiving the temperature signal, the temperature control device 20 adjusts the current to regulate the heating rate of the heating element, ultimately enabling the heating element to reach the preset temperature and reach equilibrium.

[0046] With the launch device ready, place the heating ceramic of the temperature control system on the side of the sample and heat it for a certain period of time. Once the sample 15 reaches the preset temperature, remove the temperature control heating system and prepare for the next launch operation.

[0047] In one embodiment, the impact velocity loading of this device is pneumatically loaded. A certain amount of compressed air is injected into the gas cylinder 11 via an air compressor. A pneumatic valve 10 is installed at the outlet of the gas cylinder 11. The pneumatic valve 10 is manually controlled. When high-pressure gas is injected into the gas cylinder 11, the internal pressure of the gas cylinder 11 is displayed on the digital pressure gauge above the valve. Turning the valve handle counterclockwise releases the high-pressure gas to perform work, pushing the bullet rod 7 to accelerate to a certain speed. The gas cylinder 11 is filled to the required pressure according to the required speed as shown in Table 1.

[0048] The bullet rod 7 (length l) impacts the incident rod 4 at different velocities v0, forming a square wave pulse with a pulse width of 2l / c0 that propagates along the incident rod 4. The impact velocity determines the amplitude of the pulse. By replacing the bullet rod 7 with different lengths, different pulse width loading stress waves are obtained. Table 1 is a reference table for the initial pressure and velocity of a 300mm long aluminum rod.

[0049] Table 1. Reference Table for Initial Pressure and Projectile Velocity

[0050]

[0051] In one embodiment, for the mechanical sensitivity test, the key to the test is measuring the stress state and magnitude of the explosive sample. The measured data is recorded and processed to obtain the loading conditions of the sample. Combined with the ignition situation observed by high-speed photography, the purpose of determining the ignition threshold is achieved.

[0052] The pressure measurement unit in the experiment uses a PVDF (Polyvinylidene fluorid) thin-film piezoelectric sensor. PVDF is a fluorine-containing organic piezoelectric material. This type of material is flexible, has low density, low impedance, and fast response. It is also very thin in the transverse dimension, so its influence on the energy input in the experiment is negligible. It does not require an external DC source and is easy to use. It is widely used in transient tests such as impact and explosion.

[0053] A PVDF thin-film piezoelectric sensor 22 is installed below the striking post. A detachable chassis 21 is used for easy installation of the pressure sensor, which is placed in the groove of the anvil 1. The pressure sensor and the striking post 17 are bonded to the chassis 21. The PVDF working circuit is as follows: Figure 5 The current testing circuit shown transmits amplified voltage data to an oscilloscope for storage after a resistor is connected. The recorded voltage changes characterize the charge output of the PVDF piezoelectric sensor. The chassis 21, which is equipped with a pressure sensor and impact pin 17, is detachably mounted in the groove of the anvil 1, allowing the sample chamber 2 to be replaced to accommodate impact / shear conditions.

[0054] Under the action of an impact stress pulse, the PVDF piezoelectric sensor generates an electric charge, forming a current that flows through a resistor. The amount of charge can be obtained by integrating the current flowing through the resistor.

[0055]

[0056] The relationship between the stress input and the charge generated by the PVDF piezoelectric sensor is as follows:

[0057]

[0058] Where, d 33Let be the dynamic piezoelectric coefficient of the piezoelectric film. Combining the above equations, we can obtain the relationship between the voltage signal stored in the oscilloscope and the pressure applied to the sample:

[0059]

[0060] In one embodiment, the incident stress and strain measurement unit is a strain gauge mounted on the incident rod 4, and the incident wave ε is collected by the strain gauge on the incident rod 4. i and reflected wave ε r The signal is input to the ultra-dynamic strain gauge via a Wheatstone bridge, and then amplified by the ultra-dynamic strain gauge and directly connected to the computer for storage. Under the assumption that the stresses at both ends of the specimen are balanced, the strain rate and stress of the specimen are solved by the reflected wave and the incident wave.

[0061]

[0062] The matter wave velocity in rod c0, l s Where is the specimen thickness, and E is the elastic modulus of the rod.

[0063] In one embodiment, the bullet velocity measuring unit includes a laser velocimeter 5, which is installed at the outlet of the firing tube 8. The impact velocity of the bullet rod 7 is calculated by the time it takes for the bullet rod 7 to pass between two adjacent laser beams.

[0064] A FASTCAMSA-1 high-speed camera was installed on the side of the test device to observe the ignition process of the PBX sample. The camera's amplitude frequency was 40,000 fps, the resolution was 372×312 pixels, the interval between each photo was 25 μs, the sampling time was two seconds, and it was triggered synchronously with the air gun firing.

[0065] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the foregoing description. Therefore, all changes falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0066] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A temperature and loading pulse width adjustable explosive impact-shear sensitivity tester, characterized in that: include The main loading part, which is fixed on the I-beam, includes a gas cylinder, a launching tube, a bullet rod, and an incident rod. Multiple support bases are sequentially arranged on the I-beam along the impact direction of the incident rod. The launching tube, bullet rod, and incident rod, which are coaxially arranged, are sequentially and movably arranged in the support bases from right to left. The gas cylinder is used to provide pressure to the inner cavity of the launching tube. The first end of the bullet rod passes through the inner cavity of the launching tube, and the second end of the bullet rod is used to impact the first end of the incident rod, which in turn impacts the sample. The sample chamber portion includes an anvil, a sleeve, and an impact pin. The anvil is fixed to the I-beam. A groove is formed on the anvil at a position corresponding to the second end of the incident rod. The sleeve is fitted into the groove. The impact pin is located at the bottom of the sleeve. A sample chamber is formed between the impact pin and the inner cavity of the sleeve, and the sample is placed inside the sample chamber. The temperature control section includes a heating element, a thermocouple, and a temperature control device. Both the heating element and the thermocouple are connected to the temperature control device. The heating element is used to heat the sample, and the thermocouple is used to measure the temperature of the sample and the temperature of the heating element. The testing section includes a pressure measurement unit, an incident stress and strain measurement unit, a bullet velocity measurement unit, and a photography unit. The pressure measurement unit measures the impact pressure on the sample, the incident stress and strain measurement unit measures the strain rate and stress of the sample, the bullet velocity measurement unit measures the impact velocity of the bullet rod, and the photography unit records the test process. The pressure measurement unit includes a PVDF thin-film piezoelectric sensor, which is mounted on the impact post. The PVDF thin-film piezoelectric sensor and the impact post are bonded to a chassis, which is detachably placed in the groove. The inner diameter of the sleeve is larger than the outer diameter of the incident rod, and a pressure relief hole is provided on the side of the sleeve; the striking post is made of an elastomer material, and the elastic modulus of the striking post is 2 to 3 orders of magnitude higher than that of the explosive; the heating element is a ceramic heating element, and the thermocouple located at the center of the heating element contacts the sample and collects the temperature data of the sample during the heating process; the thermocouple at the edge of the heating element is used to measure the temperature of the heating element and transmit the temperature data to an external temperature control device; the temperature control device adjusts the heating rate of the heating element by adjusting the current.

2. The explosive impact-shear sensitivity tester with adjustable temperature and loading pulse width according to claim 1, characterized in that: The entire temperature and loading pulse width adjustable explosive impact shear sensitivity tester is placed inside a protective box, and the internal reaction is observed through the tempered glass on one side of the protective box.

3. The explosive impact-shear sensitivity tester with adjustable temperature and loading pulse width according to claim 1, characterized in that: Compressed air is injected into the gas cylinder by an air compressor. A pneumatic valve is installed at the outlet of the gas cylinder. The pneumatic valve is manually controlled. A pressure gauge is also installed above the gas cylinder to display the internal pressure of the gas cylinder. The gas cylinder is filled to the required pressure according to the required impact speed.

4. The explosive impact and shear sensitivity tester with adjustable temperature and loading pulse width according to claim 1, characterized in that: The bullet rod strikes the incident rod at different velocities, creating a pulse width of 2 in the incident rod. l / c 0 The square wave pulse propagates along the incident rod, where l The length of the bullet shaft. c 0 The impact velocity of the bullet rod determines the amplitude of the pulse; different lengths of bullet rods are used to obtain stress waves with different pulse widths.

5. The explosive impact and shear sensitivity tester with adjustable temperature and loading pulse width according to claim 1, characterized in that: The incident stress and strain measurement unit is a strain gauge mounted on the incident rod, and the strain gauge on the incident rod is used to collect incident waves. and reflected waves The strain rate and stress of the specimen are solved by using reflected and incident waves.

6. The explosive impact-shear sensitivity tester with adjustable temperature and loading pulse width according to claim 1, characterized in that: The bullet velocity measuring unit includes a laser velocimeter, which is installed at the outlet of the firing tube. The impact velocity of the bullet rod is calculated by the time it takes for the bullet rod to pass between two adjacent laser beams.

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