Light-gas gun impact test system with ballistic correction function and test method

Abstract

The invention belongs to the field of material dynamic mechanical property research, and particularly relates to a light-gas gun impact test system with a ballistic correction function and a test method. A light-gas gun impact test system with a trajectory correction function is characterized in that an adaptive module is arranged at the tail end of a light-gas gun, a buffer cushion ring, a trajectory correction device and a stopper are sequentially arranged at the tail end of the adaptive module in the direction facing a target plate, the trajectory correction device comprises a correction base, a transition section and a straight column section, speckle marking is conducted on a sample through a calibration assembly, and the calibration assembly is connected with the buffer cushion ring. The magnetic velometer is electrically connected with the oscilloscope, the oscilloscope is electrically connected with the high-speed camera, a trigger pulse signal is output after a voltage pulse signal output by the magnetic velometer is processed by the oscilloscope, and the high-speed camera starts shooting and records the impact process of the sample after receiving the trigger pulse signal. According to the test system and method, detachable connection is achieved through a standardized interface, universality and scene adaptability are both considered, and operation standardization and result reliability are ensured.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of material dynamic mechanical property research, and particularly relates to a light gas gun impact test system with trajectory correction and a test method. BACKGROUND

[0002] As the core driving equipment of high-speed impact test, the light gas gun is widely used in the fields of material dynamic mechanical property research and equipment anti-impact design verification due to the advantages of stable launching pressure and controllable projectile initial speed. However, in the existing light gas gun impact test system, there are common core pain points of "modular dispersion, poor coordination and broken data chain", which seriously restrict the test accuracy and efficiency. The light gas gun, impact assembly and test assembly are usually designed and installed as independent hardware units, and the interface standardization degree between them is low. The mechanical connection, centering and sealing of each test consume a lot of time and effort. Each subsystem is usually equipped with an independent control system, and the operator needs to switch between multiple interfaces, which is difficult to realize unified timing planning and centralized control. The success of the test is highly dependent on the accurate coordination of nanoseconds to microseconds. For example, at the moment when the projectile reaches the target, the high-speed camera must start recording at the right time, the laser speedometer needs to be turned on in advance and work stably, and the dynamic strain gauge needs to be in a triggered waiting state. At present, the delay trigger is mainly set by manual experience, and the internal clock of each device may have a deviation, which leads to the loss or invalidity of key data.

[0003] The coordination error will directly introduce measurement uncertainty. For example, clock asynchronization will cause the strain history and image time label to be inconsistent, affecting the inversion accuracy of the constitutive model parameters. A large amount of time is consumed in mechanical assembly, line connection, parameter debugging and manual data processing, rather than core scientific analysis. The preparation cycle of a successful impact test may be as long as several days or even weeks, which is highly dependent on the experience and on-site judgment of the operator, and the risk of human error is high, which makes it difficult to ensure the reproducibility of the test results under the same parameters, which is a big taboo in scientific research. SUMMARY

[0004] The purpose of the present application is to overcome the deficiencies in the prior art, and to provide a light gas gun impact test system with trajectory correction and a test method. The system and method are detachably connected through a standardized interface, and take into account the universality and scene adaptability. The method follows a closed-loop process of "assembly-calibration-test-processing", which ensures the standardization of operation and the reliability of results.

[0005] To solve the above technical problems, the application adopts the following technical solutions: on one hand, the application discloses a light gas gun impact test system with ballistic correction, which comprises a light gas gun, a test sample and a target plate, a magnetic speed detector is arranged on the light gas gun, and a high-speed camera is further included; an adaptive module is arranged at the end of the light gas gun, the adaptive module is in a cylindrical structure, a channel is formed in the hollow interior of the adaptive module, the channel is a seamless coaxial extension of the launching channel of the light gas gun barrel, a buffer pad ring, a ballistic corrector and a stopper are sequentially arranged at the end of the adaptive module towards the target plate, and the center of the buffer pad ring, the ballistic corrector and the stopper are all provided with perforations, and each perforation is coaxial with the launching channel of the light gas gun barrel and the adaptive module.

[0006] The ballistic corrector comprises a correction base, a gradual change section and a straight column section, the correction base is sleeved outside the adaptive module and fixedly connected with the buffer pad ring, and the diameter of the gradual change section gradually decreases from the correction base to the straight column section, and the stopper is sleeved outside the adaptive module.

[0007] The diameter of the launching channel of the light gas gun barrel is consistent with the diameter of the channel of the adaptive module, the diameter of the perforation of the buffer pad ring is smaller than the diameter of the channel of the adaptive module and consistent with the diameter of the perforation of the correction base, the diameter of the perforation of the straight column section of the ballistic corrector is smaller than the diameter of the correction base, and the diameter of the perforation of the stopper is greater than the diameter of the perforation of the straight column section of the ballistic corrector.

[0008] The test sample is marked by speckle by a calibration assembly and launched by the light gas gun to the target plate, the magnetic speed detector is electrically connected with an oscilloscope, and the oscilloscope is electrically connected with the high-speed camera, the voltage pulse signal output by the magnetic speed detector is processed by the oscilloscope and then output as a trigger pulse signal, the high-speed camera starts shooting after receiving the trigger pulse signal and records the impact process of the test sample.

[0009] Preferably, the interface end faces of the barrel of the light gas gun and the adaptive module are both subjected to ultrahigh flatness processing and sealed, and the two are butted through an adapter flange.

[0010] Preferably, the buffer pad ring is made of 45 steel, and the buffer pad ring is fixedly connected with the end of the adaptive module.

[0011] Preferably, the taper angle of the gradual change section is 2.86°, and the surface roughness Ra is less than or equal to 1.6 μm; the cylindricity of the straight column section is less than or equal to 0.005 mm, and the surface roughness Ra is less than or equal to 0.8 μm; and the length ratio of the gradual change section to the straight column section is 2:3.

[0012] Preferably, the calibration assembly includes a Type I calibration assembly, a Type II calibration assembly, and a Type III calibration assembly. The Type I calibration assembly includes a horizontal calibration base and a vertical calibration sleeve, with a plurality of evenly spaced perforated grooves on the calibration sleeve. The sample is placed inside the calibration sleeve and sprayed to form a mark consistent with the shape of the grooves. The Type II calibration assembly includes a horizontal calibration base and a vertical calibration sleeve, with a plurality of evenly spaced calibration through holes on the surface of the calibration sleeve. The sample is placed inside the calibration sleeve and sprayed to form a speckle mark consistent with the calibration through holes. The Type III calibration assembly includes... The system includes a calibration base, a dot matrix sleeve, and a slotted sleeve. A semi-cylindrical fixing groove is provided inside the calibration base. The dot matrix sleeve is a hollow semi-cylindrical structure with the same dimensions as the fixing groove. Several regularly arranged calibration through holes are formed on the surface of the dot matrix sleeve. The dot matrix sleeve is placed inside the fixing groove, forming a cylindrical structure. The sample is placed inside this cylindrical structure. A slotted sleeve is fitted onto the outside of the dot matrix sleeve. A spray groove with the same diameter as the calibration through holes is formed on the slotted sleeve. The sample, within the cylindrical structure, is sprayed to form speckle marks corresponding to the position of the spray groove and consistent with the shape of the calibration through holes.

[0013] Preferably, the coaxiality of the light air gun barrel, adapter module, buffer ring, ballistic corrector and stopper is ≤0.01mm.

[0014] On the other hand, a method for testing the impact of a light gas gun with ballistic correction includes the following steps: S1: Connect the light gas gun launch tube to the adapter module by thread, install a buffer ring at the end of the adapter module, put a ballistic corrector on the outside of the buffer ring, put a stopper on the outside of the ballistic corrector, and make electrical connections to the magnetometer, oscilloscope and high-speed camera to complete the connection of the test device. S2: Use the calibration kit to mark the speckle pattern on the blank bullets that are exactly the same as the sample in terms of mass and shape. Fire three sets in a row to complete the ballistic calibration, high-speed camera centering and speckle mark verification. S3: Use the calibration components to mark the test sample with speckle and install it into the light air gun. Start the light air gun and use the high-speed camera to capture multiple sets of high-speed image sequences. Use each speckle to track the changes in the Lagrange position point. S4: Establish the coordinate mapping relationship before and after deformation of each Lagrange position point, integrate launch parameters, image data, and mechanical parameters, and generate a test report.

[0015] Preferably, the coaxiality of the adapter module and the transmitter tube is detected by a laser interferometer. If the deviation is >0.01mm, the screw-in depth is finely adjusted until the deviation is ≤0.01mm.

[0016] Preferably, when using blank cartridge calibration, the positional deviation of the impact point in three consecutive tests is ≤0.2mm.

[0017] The beneficial effects of this invention are as follows: 1. Improved the accuracy and reliability of impact tests. (1) Through the gradual section and straight column section structure of the ballistic corrector, the flight attitude of the projectile was effectively guided and corrected, reducing yaw, roll and other phenomena, and ensuring that the sample impacted the target plate in a stable attitude; (2) Through precision machining and assembly, the coaxiality of the launch channel, buffer ring, ballistic corrector and stopper was ensured, and the ballistic deviation was minimized; (3) The ballistic calibration and camera centering were performed using empty projectiles, and the coaxiality was detected by laser interferometer, ensuring that the system reached the optimal state before the formal test.

[0018] 2. Accurate measurement and recording of dynamic processes were achieved. (1) The magnetic velocimeter, oscilloscope and high-speed camera are linked together. The high-speed camera is precisely triggered by the voltage pulse signal to capture the dynamic process of the impact moment. (2) Regular speckle or groove marks are formed on the sample surface by three types of calibration components, which can accurately track the deformation trajectory of the Lagrange position point. (3) The emission parameters, image data and mechanical parameters are integrated to generate a comprehensive test report, providing a complete data chain for the study of material dynamic response.

[0019] 3. Enhance the adaptability and flexibility of the system through modular design. (1) The adapter module is a seamless extension of the gun barrel. It is connected by an adapter flange, which is convenient to adapt to different specifications of light gas guns or test requirements; (2) The three types of calibration components support speckle marking of specimens of different shapes and sizes, which are suitable for a variety of materials and test scenarios; (3) The buffer ring absorbs part of the impact energy, and the stopper limits the displacement of the ballistic corrector, protecting the structural stability of the system. The system installation and disassembly time can be ≤2min / time, and the acquisition, centering and focusing time can be ≤5min. A single person can complete the entire process operation.

[0020] 4. Improve test efficiency and repeatability. (1) Verify ballistics and marking effects by firing blanks to reduce trial and error costs and improve the success rate of formal tests; (2) Quantitative standards such as impact point position deviation ≤0.2mm and coaxiality ≤0.01mm ensure the consistency and comparability of multiple test results. Compared with traditional methods, the test repeatability is improved by 30%; (3) The entire process of electrical signal triggering and image recording is automated to reduce human intervention errors.

[0021] 5. Balancing safety and durability. (1) The gun barrel and the adapter module interface are machined and sealed with ultra-high flatness to prevent gas leakage. The buffer ring and the ballistic corrector are made of high-strength materials and can withstand repeated impacts. (2) The ballistic corrector has a high surface finish design for the transition section and the straight column section, which reduces friction interference and extends the life of the components. The damage rate of the sample caused by calibration or clamping is reduced to ≤5%. The life of core components such as the ballistic corrector and the buffer ring is ≥800 times. The maintenance cost is reduced by 40% and the processing cost is reduced by 60%. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the ballistic corrector in this invention; Figure 3 This is a schematic diagram of the structure of the Type I calibration component in this invention; Figure 4 This is a schematic diagram of the structure of the Type II calibration component in this invention; Figure 5 This is a schematic diagram of the structure of the Type III calibration component in this invention; Figure 6 This is a schematic diagram of the calibration base in the Type III calibration assembly; Figure 7 This is a schematic diagram of the dot matrix sleeve in the Type III calibration assembly; Figure 8 This is a schematic diagram of the slotted sleeve in the Type III calibration assembly.

[0023] Figure label: 1. Light air gun; 2. Target plate; 3. Magnetic velocity measuring device; 4. High-speed camera; 5. Adapter module; 6. Buffer pad ring; 7. Ballistic corrector; 71. Correction base; 72. Gradient section; 73. Straight column section; 8. Stopper; 9. Calibration assembly; 91. Type I calibration assembly; 92. Type II calibration assembly; 93. Type III calibration assembly; 94. Calibration base; 941. Fixing groove; 95. Calibration sleeve; 96. Groove; 97. Calibration through hole; 98. Dot matrix sleeve; 99. Slotted sleeve; 991. Spraying groove; 10. Oscilloscope; 11. Adapter flange; 12. Sample. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] Example 1: As Figure 1As shown, this invention discloses a light air gun impact test system with ballistic correction, including a light air gun 1, a sample and a target plate 2. A magnetic velocity measuring device 3 is installed on the light air gun 1, and a high-speed camera 4 is also included. An adapter module 5 is installed at the end of the light air gun 1. The adapter module 5 has a cylindrical structure with a hollow interior forming a channel. This channel is a seamless coaxial extension of the firing channel of the light air gun 1 barrel. At the end of the adapter module 5, facing the target plate 2, a buffer ring 6, a ballistic corrector 7 and a stopper 8 are arranged in sequence. The buffer ring 6, the ballistic corrector 7 and the stopper 8 are all provided with perforations at their centers, and each perforation is coaxial with the firing channel of the light air gun 1 barrel and the adapter module 5.

[0026] The interface faces of the barrel of the light air cannon 1 and the adapter module 5 are both machined to a very high degree of flatness and sealed. The two are connected via an adapter flange 11. The adapter module 5 is made of 304 stainless steel. The internal thread hole of the adapter module 5 and the external thread of the barrel of the light air cannon 1 are assembled using a mating drilling process to minimize the cumulative error caused by separate machining and ensure that the axes of the two parts are naturally aligned when the threads are screwed together, with a coaxiality ≤0.01mm. The buffer ring 6 is made of 304 stainless steel or 45 steel and is fixed to the adapter module 5, while the stopper 8 is also firmly fixed to the adapter module 5.

[0027] like Figure 2 As shown, the ballistic corrector 7 includes a corrective base 71, a tapered section 72, and a straight section 73. The corrective base 71 is fitted onto the outside of the adapter module 5 and fixedly connected to the buffer ring 6. The diameter of the tapered section 72 gradually decreases from the corrective base 71 to the straight section 73. The stopper 8 is fitted onto the outside of the adapter module 5. The corrective base 71 and the adapter module 5 are interference-fitted. The ballistic corrector 7 is made of 45 steel, and its tapered section 72 has a length of 20mm and a cone angle of 2.86° (in...). Figure 2 To make the details more prominent, the cone angle was specially enlarged. The surface roughness Ra is ≤1.6 μm, the maximum diameter is 12 mm, and the minimum diameter is 10 mm. The diameter of the straight column section 73 is 10 mm, the length is 30 mm, the cylindricity is ≤0.005 mm, the surface roughness Ra is ≤0.8 μm, the diameter of the central through hole is 10 mm, and the coaxiality between the correction base 71, the gradient section 72 and the straight column section 73 is ≤0.01 mm.

[0028] The 45 steel bar used for the ballistic corrector 7 is quenched at 860 ℃ and tempered at +550 ℃, with the hardness controlled at 220-250 HB; the straight column section 73 is precision ground by an external cylindrical grinder, the gradient section 72 is cut by a CNC lathe, and the central through hole is machined by a deep hole drill.

[0029] The diameter of the firing channel of the light gas gun 1 is the same as the channel diameter of the adapter module 5. The diameter of the perforation of the buffer ring 6 is smaller than the diameter of the channel of the adapter module 5 and is the same as the diameter of the perforation of the correction base 71. The diameter of the perforation of the straight column section 73 of the ballistic corrector 7 is smaller than the diameter of the correction base 71. The diameter of the perforation of the stopper 8 is larger than the diameter of the perforation of the straight column section 73 of the ballistic corrector 7.

[0030] The coaxiality between the gun barrel and the adapter module 5, the buffer pad ring 6, the ballistic corrector 7 and the stopper 8 is ≤0.01mm, and the overall installation error is ≤0.5mm.

[0031] The sample is marked with speckle by the calibration component 9 and launched onto the target plate 2 by the light air gun 1. The magnetic velocimeter 3 is electrically connected to the oscilloscope 10, and the oscilloscope 10 is electrically connected to the high-speed camera 4. The voltage pulse signal output by the magnetic velocimeter 3 is processed by the oscilloscope 10 and then output as a trigger pulse signal. The high-speed camera 4 receives the trigger pulse signal and starts shooting to record the impact process of the sample.

[0032] like Figures 3-5 As shown, the calibration assembly 9 includes a type I calibration assembly 91, a type II calibration assembly 92, and a type III calibration assembly 93. The type I calibration assembly 91 includes a horizontal calibration base 94 and a vertical calibration sleeve 95, with several evenly spaced perforated grooves 96 on the calibration sleeve 95. The sample is placed inside the calibration sleeve 95 and sprayed to form a mark consistent with the shape of the grooves 96. The type II calibration assembly 92 includes a horizontal calibration base 94 and a vertical calibration sleeve 95, with several evenly spaced calibration through holes 97 on the surface of the calibration sleeve 95. The sample is placed inside the calibration sleeve 95 and sprayed to form a speckled mark consistent with the calibration through holes 97. The type III calibration assembly... Component 93 includes a calibration base 94, a dot matrix sleeve 98, and a slotted sleeve 99. A semi-cylindrical fixing groove 941 is provided inside the calibration base 94. The dot matrix sleeve 98 is a hollow semi-cylindrical structure with several regularly arranged calibration through holes 97 on its surface. The dot matrix sleeve 98 is placed inside the fixing groove 941, and the sample is placed inside the dot matrix sleeve 98. The slotted sleeve 99 is fitted on the outside of the dot matrix sleeve 98. The slotted sleeve 99 has a spraying groove 991 with the same diameter as the calibration through holes 97. The sample is sprayed in the cylindrical structure formed by the fixing groove 941 and the dot matrix sleeve 98 to form speckle marks that correspond to the position of the spraying groove 991 and have the same shape as the calibration through holes 97.

[0033] like Figure 3As shown, the calibration base 94 of the Type I calibration component 91 has a diameter of 40mm, a thickness of 10mm, and a roundness error of ≤0.01mm after machining to ensure horizontality during placement. The calibration sleeve 95 has an outer diameter of 12mm, an inner diameter of 10.5mm, and a height of 40mm. The calibration base 94 and calibration sleeve 95 are connected by argon arc welding with a perpendicularity of ≤0.02mm to avoid calibration errors caused by tilting. The grooves 96 have a spacing of 2.4mm, a groove width of 0.6mm, and an accuracy of ±0.01mm to ensure the accuracy of the marking position. This type of calibration component 9 is a general-purpose type. Markings consistent with the grooves 96 can be sprayed on the sample, and then several speckled marks can be added between these marks on the test surface as needed. To enhance contrast, other colors can also be pre-sprayed on the sample. It is suitable for routine Taylor impact tests, batch sample testing, and other scenarios, and is especially suitable for applications requiring reusable calibration components to control the cost of a single test. Its advantages lie in the high strength of 45# steel, which can withstand minor impacts during testing without being easily damaged, and the 96 grooves on the surface can be washed and cleaned and reused, greatly reducing long-term testing costs. Its disadvantages are that the structural design is limited to circumferential full-range calibration, which cannot focus on specific local areas of the sample and is difficult to meet the needs of refined local deformation analysis.

[0034] like Figure 4As shown, the Type II calibration component 92 is integrally formed using 3D printing technology, with a layer height of 0.1 mm and an infill rate of ≥80%. The calibration sleeve 95 has an inner diameter of 10.6 mm, a calibration through-hole 97 with a diameter of 1.5 mm, a row and column spacing of 3 mm, and an adjacent spacing of 1.5 mm, arranged in an alternating pattern. This type of calibration component 9 is suitable for sample calibration in rapid experiments, where speckle markings are directly sprayed onto the sample. In actual experiments, this type of calibration component 9 is a rapid calibration component, using PLA as the substrate as the whole, requiring no subsequent assembly, and can be quickly customized for production. All components are formed simultaneously, avoiding assembly errors that affect calibration accuracy. Its calibration base 94 is disc-shaped, with a diameter of 40 mm and a thickness of 10 mm. During 3D printing, the layer height is set to 0.1 mm and the infill rate to 80%, ensuring that the calibration base 94 is strong enough to support the calibration sleeve 95. The calibration sleeve 95 is a hollow structure with an inner diameter of 10.6 mm, a height of 40 mm, and a wall thickness of 0.7 mm. It has a printing accuracy of ±0.1 mm and can accommodate most standard-sized samples. The calibration sleeve 95 features staggered calibration through-holes 97 with a dot matrix position error ≤0.1 mm. This calibration component 9 meets conventional calibration accuracy requirements and is suitable for rapid screening tests and low-cost single-test scenarios, especially suitable for needs requiring the calibration of multiple sets of samples in a short time without the need for reusing calibration parts. Its advantages include rapid customization via 3D printing, with a single-piece printing cycle of only 2 hours, and the low cost of PLA material, making it suitable for low-cost testing needs. Simultaneously, the calibration operation is highly efficient, drying and usable within 20 minutes after painting, significantly shortening test preparation time. The disadvantages are that PLA material is not resistant to solvent corrosion, cannot be cleaned by washing, is only suitable for single use, and has relatively low strength, making it easily damaged by impact and unsuitable for scenarios requiring long-term reusability.

[0035] like Figures 5-8As shown, the calibration base 94 of the Type III calibration component 93 has a semi-cylindrical fixing groove 941 with a diameter of 10 mm and a length of 50 mm. The dot matrix sleeve 98 has several regularly arranged calibration through holes 97 embedded in the fixing groove 941, with a machining accuracy of ±0.005 mm. The slotted sleeve 99 is a hollow semi-cylindrical structure with an inner diameter of 14 mm, an outer diameter of 16 mm, and a length of 80 mm. The spraying groove 991 has a width of 1 mm and a length of 70 mm and is snap-fitted onto the calibration base 94. In use, the sample is inserted into the dot matrix sleeve 98, and speckle markings are sprayed onto the sample through the spraying groove 991 and the calibration through holes 97 of the dot matrix sleeve 98. This calibration component 9 is made of stainless steel. The calibration base 94, slotted sleeve 99, and lattice sleeve 98 are all 3D printed from metal. Pre-installed assembly gaps ensure high precision and structural compatibility, making it suitable for sample calibration in high-precision experiments. It does not produce speckle marking diffusion. It enables fine position marking and is suitable for high-precision constitutive model verification, local deformation analysis, and other scenarios, especially for experiments requiring focusing on specific areas of the sample (such as areas of concentrated impact stress) to obtain microscopic mechanical information. Its advantages include the high stability and resistance to deformation of stainless steel, high 3D printing precision, and the ability to meet high-requirement position traceability requirements. The separate structure supports roller rotation adjustment, allowing precise alignment of local sample areas for half-field local calibration. The disadvantages are that the structural design only covers half of the sample area; to obtain full-range calibration information, multiple adjustments and repeated operations are required, and the high-precision manufacturing process results in a higher unit cost than the previous two calibration components.

[0036] When using the sample, it is first inserted into the sleeve 95 of the selected calibration component 9 for fixation, with the axes parallel and the spacing deviation ≤0.4mm. The sample is then sprayed, leaving grooves 96 or calibration through holes 97 on the sample. After drying, it is installed in the light air gun 1 for use. When there are no breaks or blurs in the image sequence captured by the high-speed camera 4, the calibration is qualified, and then formal testing can be carried out.

[0037] During the recording experiment, an industrial-grade high-speed camera (4) with a maximum frame rate of 10 was used. 5 The system operates at 1920*1080 FPS with two symmetrically positioned LED fill lights, angled at 45° to the axis of the high-speed camera 4 to avoid shadows and reflections. During testing, laser alignment of the light gas cannon 1, target plate 2, etc., is first performed, followed by high-speed camera alignment and focusing. After alignment and focusing, data on launch pressure, sample velocity, deformation images, and calibration marks are simultaneously acquired.

[0038] On the other hand, this invention discloses an impact test method for a light gas gun 1 with ballistic correction, comprising the following steps: S1: Connect the launch tube of the light air gun 1 to the adapter module 5 by thread, install the buffer ring 6 at the end of the adapter module 5, put the ballistic corrector 7 on the outside of the buffer ring 6, put the stopper 8 on the outside of the ballistic corrector 7, and make electrical connections to the magnetic velocity meter, oscilloscope 10 and high-speed camera 4 to complete the connection of the test device. S2: Use calibration component 9 to mark speckle patterns on empty bullets that are exactly the same as the sample in terms of mass and shape. Fire three sets of bullets in succession to complete the ballistic calibration, centering of high-speed camera 4 and verification of speckle patterns. S3: Use the calibration component 9 to mark the test sample with speckle and install it into the light air gun 1. Start the light air gun 1 and the high-speed camera 4 to capture multiple sets of high-speed image sequences. Use each speckle to track the changes in the Lagrange position point. S4: Establish the coordinate mapping relationship before and after deformation of each Lagrange position point, integrate launch parameters, image data, and mechanical parameters, and generate a test report.

[0039] The coaxiality of the adapter module 5 and the launch tube is detected by a laser interferometer. When the deviation is >0.01mm, the screw-in depth is finely adjusted until the deviation is ≤0.01mm. When using blank bullet calibration, the position deviation of the impact point is ≤0.2mm for three consecutive times.

[0040] The test samples used in this test method include, but are not limited to, cylindrical specimens for Taylor impact testing and rod-shaped specimens for Hopkinson bar testing. The distance between the specimen and the straight column section 73 of the ballistic correction module is 5 mm. The data processing back-calculation error is ≤0.02 mm. Each test is repeated 3 times. The device is recalibrated when the data deviation is >10%.

[0041] Example 2: Taking the Taylor impact test of No. 10 steel (10 mm caliber light gas gun, firing pressure 50.2 MPa) as an example, the application of the device is described in detail. The test sample (No. 10 steel, 10 mm in diameter, 50 mm in length) is selected and its surface is ground to Ra ≤ 1.6 μm; the ballistic corrector 7 and the selected calibration component are assembled, and the coaxiality and spacing are calibrated; the high-speed camera 4 lens is aligned with the calibration component and the sample (focal length 50 mm, aperture f / 8), and the frame rate is set to 10. 5The test involves firing blanks of equal mass (10g) to the test projectile, with a trigger delay of 10 ms. High-speed camera 4 records the trajectory and measures the deviation of the projectile impacting the virtual target. The calibrated sample is fixed to the target position of the impact device (5 mm distance from the straight column section 73 of the ballistic corrector 7). The projectile is fired, and high-speed camera 4 synchronously records the deformation process. Image data is saved after the test. High-speed images are imported using image processing software (such as ISPEED), and a coordinate mapping relationship before and after deformation is established using the groove 96 or dot matrix of the calibration component as a reference (error ≤ 0.02 mm). The strain field distribution and dynamic yield strength of the sample are calculated, and the microstructure test data is correlated. The ballistic corrector 7 can be replaced after approximately 50 experiments to ensure experimental accuracy. Before the test, the trigger synchronization of high-speed camera 4 is checked (error ≤ 1 ms) to avoid data loss. Each test group is repeated 3 times. If the data deviation is > 10%, the components are recalibrated and retested to ensure the reliability of the results.

[0042] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A light gas gun impact test system with ballistic correction, comprising a light gas gun, a test sample and a target plate, a magnetic velocity meter is arranged on the light gas gun, characterized in that: The high-speed camera is provided with an adapter module at the end of the light gas gun, the adapter module is a cylindrical structure, a channel is formed in the inside of the adapter module, the channel is a seamless coaxial extension of the launching channel of the light gas gun barrel, a buffer pad ring, a ballistic corrector and a stopper are sequentially arranged at the end of the adapter module towards the target plate, the buffer pad ring, the ballistic corrector and the stopper are provided with through holes at the centers thereof, and the through holes are coaxial with the launching channel of the light gas gun barrel and the channel of the adapter module, The ballistic corrector comprises a correction base, a gradual change section and a straight column section, the correction base is sleeved outside the adapter module and is fixedly connected with the buffer pad ring, and the diameter of the gradual change section gradually decreases from the correction base to the straight column section, and the stopper is sleeved outside the adapter module, The diameter of the launching channel of the light gas gun barrel is consistent with the diameter of the channel of the adapter module, the diameter of the through hole of the buffer pad ring is smaller than the diameter of the channel of the adapter module and is consistent with the diameter of the through hole of the correction base, the diameter of the through hole of the straight column section of the ballistic corrector is smaller than the diameter of the correction base, and the diameter of the through hole of the stopper is greater than the diameter of the through hole of the straight column section of the ballistic corrector, The sample is marked by speckle by the calibration assembly and is launched on the target plate by the light gas gun, the magnetic velocity meter is electrically connected with the oscilloscope, the oscilloscope is electrically connected with the high-speed camera, the voltage pulse signal output by the magnetic velocity meter is processed by the oscilloscope to output a trigger pulse signal, the high-speed camera starts shooting after receiving the trigger pulse signal and records the impact process of the sample.

2. The light gas gun impact test system with ballistic correction of claim 1, wherein: The interface end faces of the barrel of the light gas gun and the adapter module are subjected to ultrahigh flatness processing and are sealed, and the two are butted through an adapter flange.

3. The light gas gun impact test system with ballistic correction of claim 1, wherein: The buffer pad ring is made of 45 steel and is fixedly connected with the end of the adapter module.

4. The light gas gun impact test system with ballistic correction of claim 1, wherein: The taper angle of the gradual change section is 2.86°, and the surface roughness Ra is less than or equal to 1.6 μm; the cylindricity of the straight column section is less than or equal to 0.005 mm, and the surface roughness Ra is less than or equal to 0.8 μm; and the length ratio of the gradual change section to the straight column section is 2:

3.

5. The light gas gun impact test system with ballistic correction of claim 1, wherein: The calibration assembly comprises a type I calibration assembly, a type II calibration assembly and a type III calibration assembly, The type I calibration assembly comprises a calibration base in the horizontal direction and a calibration sleeve in the vertical direction, and a plurality of uniformly spaced hollow grooves are arranged on the calibration sleeve, the sample is placed in the calibration sleeve, and a mark consistent with the shape of the groove is formed by spraying, The type II calibration assembly comprises a calibration base in the horizontal direction and a calibration sleeve in the vertical direction, and a plurality of uniformly spaced calibration through holes are arranged on the surface of the calibration sleeve, the sample is placed in the calibration sleeve, and a speckle mark consistent with the calibration through hole is formed by spraying, The type III calibration assembly comprises a calibration base, a dot array sleeve and a slotted sleeve, a semicylindrical fixing groove is arranged in the calibration base, the dot array sleeve is a hollow semicylindrical structure and is consistent in size with the fixing groove, a plurality of regularly arranged calibration through holes are arranged on the surface of the dot array sleeve, the dot array sleeve is placed in the fixing groove, the dot array sleeve and the fixing groove form a cylindrical sleeve structure, a sample is placed in the sleeve structure, and the slotted sleeve is sleeved outside the dot array sleeve, the slotted sleeve is provided with spraying grooves which are consistent in diameter with the calibration through holes; the sample in the sleeve structure is sprayed to form speckle marks which are consistent in shape with the calibration through holes and correspond to the positions of the spraying grooves.

6. The light gas gun impact test system with ballistic correction of claim 1, wherein: The coaxiality of the light gas gun barrel, the adapter module, the buffer pad ring, the ballistic corrector and the stopper is ≤0.01mm.

7. A method of using the light gas gun shock test system with trajectory correction according to any one of the preceding claims, characterized in that: The method comprises the following steps: S1: the light gas gun barrel is threadedly connected with the adapter module, the buffer pad ring is installed at the end of the adapter module, the ballistic corrector is sleeved outside the buffer pad ring, the stopper is sleeved outside the ballistic corrector, the magnetic speed meter, the oscilloscope and the high-speed camera are electrically connected, and the connection of the test device is completed; S2: the calibration assembly is used for speckle marking of a dummy projectile which is completely same in mass and shape as the sample, three groups of continuous shots are fired, ballistic calibration, centering of the high-speed camera and verification of the speckle marking are completed; S3: the calibration assembly is used for speckle marking of the sample to be tested, and the sample is installed in the light gas gun, the light gas gun is started, a plurality of high-speed image sequences are captured by the high-speed camera, and the changes of the Lagrangian position points are tracked by using each speckle point; S4: the coordinate mapping relationship of each Lagrangian position point before and after deformation is established, the test report is generated by integrating the launch parameters, image data and mechanical parameters.

8. The light gas gun impact test method with ballistic correction of claim 7, wherein: The coaxiality of the adapter module and the barrel is detected by a laser interferometer, when the deviation is >0.01mm, the depth of rotation is adjusted until the deviation is ≤0.01mm.

9. The light gas gun impact test method with ballistic correction of claim 7, wherein: When the dummy projectile is used for calibration, the position deviation of three continuous impact points is ≤0.2mm.

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