Freezing device and method for recovering the state of shaped charge material collapsed by pressure

Abstract

This invention relates to a freezing device and method for recovering the material state of a shaped charge in the event of collapse. It includes a secondary propellant column, a main propellant column, a shaped charge, a stopper block, and multiple shells. The main propellant column is primarily cylindrical, with the secondary propellant column mounted on its upper surface. The shaped charge is mounted on the lower part of the main propellant column. The inner diameter of the shell is smaller than the diameter of the main propellant column but larger than the inner diameter of the larger end of the shaped charge. The stopper block consists of a frustum section and a cylindrical section, with the shape of the frustum section matching the shape of the shaped charge. The shells are placed on the ground, the stopper block is placed inside the shells, and one end of the cylindrical section is placed on the ground inside the shells. The distance between the stopper block and the shaped charge is adjustable by changing shells of different heights. Multiple tests were conducted with only the distance varying. This invention achieves the freezing and recovery of the material state of the shaped charge at the typical collapse moment under extreme loading conditions and explores the high-speed deformation mechanism of the corresponding material during the collapse of the shaped charge.

Description

Technical Field

[0001] This invention belongs to the field of shaped charge technology, specifically relating to a shaped charge freezing device and method for recovering shaped charge frozen materials in a state of collapse. Background Technology

[0002] As a core component of armor-piercing projectiles, the shaped charge liner material is a crucial factor affecting the armor-piercing and perforation capabilities of shaped charge projectiles. To form a high-speed, continuous shaped charge jet, the shaped charge liner material should possess properties such as high density, high ductility, and high sound velocity.

[0003] Currently, copper and copper alloys are the mainstream materials used for shaped charge liner materials both domestically and internationally. However, the performance of copper shaped charge liners has reached its limit. Therefore, seeking new shaped charge liner materials that surpass copper to improve the penetration performance of armor-piercing projectiles remains a major problem that urgently needs to be solved. In recent years, active shaped charge liner materials that can release energy through chemical reactions while meeting kinetic energy penetration requirements have shown better lateral hole-expanding effects than copper materials, demonstrating great potential for application in shaped charge liner materials. However, there are no corresponding standards for the selection of active shaped charge liner materials.

[0004] During jet forming, the propellant liner undergoes complex stress processes, including the collapse of the material by the detonation wave, the compression during axial convergence, and the stretching after jet forming. Under these extreme high-temperature, high-pressure, and high-strain-rate loading conditions, the initial state of the propellant liner material and the changes in its state during jet formation both influence its continuous jet forming and penetration performance. However, due to limitations in experimental conditions, there is currently limited research on the deformation behavior of propellant liners under ultra-high strain rates. Our understanding of the collapse of the propellant liner and the deformation behavior of metallic materials during jet forming under such extreme loading conditions is scarce, and the intuitive characterization of the chemical reaction behavior of the active propellant liner material during experiments also lacks richer and more refined exploration. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for freezing shaped charge materials in a state of collapse, which can ensure that the active material of the shaped charge structure and the shaped charge material in a typical collapse process are "frozen" under high temperature, high pressure and high strain rate loading conditions.

[0006] The technical solution to achieve the purpose of this invention is: a shaped charge freezing device for recovering the crushed active drug liner material state, comprising a secondary drug column, a main drug column, an active drug liner, a plug block, and multiple cylindrical shells of the same diameter but different heights;

[0007] The main charge is cylindrical in shape. The upper end of the main charge is fitted with a secondary charge for detonating the main charge. The lower part of the main charge is a frustum-shaped groove. The frustum-shaped groove is fitted with an active shaped charge shroud of a matching shape. The inner diameter of the shroud is smaller than the diameter of the main charge and larger than the inner diameter of the large end of the active shaped charge shroud. The plug is composed of a frustum section and a cylindrical section, and the shape of the frustum section matches the shape of the active shaped charge shroud.

[0008] The shell is placed on the ground or workbench, the plug is placed inside the shell, and one end of the cylindrical section is placed on the ground or workbench inside the shell. By changing the shell of different heights, the distance between the plug and the active drug liner can be adjusted. Multiple tests are conducted with only different distances, so as to achieve the freezing and recovery of the state at different times during the jet forming process of the crushed active drug liner material.

[0009] Furthermore, it has multiple plugs of different sizes and a cylindrical shell;

[0010] When the distance between the generatrix of the stopper frustum and the generatrix of the active pharmaceutical ingredient shroud is 0, the height of the cylindrical segment of the stopper is 0; when the distance between the generatrix of the stopper frustum and the generatrix of the active pharmaceutical ingredient shroud is greater than 0, the height of the cylindrical segment of the stopper is greater than or equal to the distance between the upper surface of the stopper frustum and the top of the active pharmaceutical ingredient shroud.

[0011] Furthermore, the auxiliary charge, main charge, active charge liner, plug, and shell are coaxially arranged. The auxiliary charge uses low-detonation-velocity, low-explosion-pressure explosive, while the main charge uses high-detonation-velocity, high-explosion-pressure explosive.

[0012] Furthermore, the auxiliary explosive and the main explosive are molded and pressed together. The auxiliary explosive adopts a single-point center initiation method and uses TNT explosive, while the main explosive uses 8701 explosive.

[0013] Furthermore, the plug is made of a material with a different composition from the active pharmaceutical ingredient liner, and with lower strength but better toughness than the liner.

[0014] The shell is made of low-density metal or polymer materials.

[0015] Furthermore, the stopper is made of copper, aluminum, or rubber; the shell is made of aluminum, nylon, or polycarbonate.

[0016] Furthermore, the active pharmaceutical cover is made by cold pressing, high-temperature sintering or high-temperature melting of active materials; the active materials used in the active pharmaceutical cover are metal mixtures, amorphous alloys or high-entropy alloys.

[0017] Furthermore, the active drug liner is a drug liner with equal or variable wall thickness; the shape of the active drug liner is conical, tulip-shaped, or trumpet-shaped; and the length-to-diameter ratio of the main drug column is 1 to 1.3.

[0018] Furthermore, the main drug column, the auxiliary drug column, the outer surface of the active drug liner, and the end face of the shell are coated with shellac.

[0019] A method for freezing a state using the above-described apparatus includes the following steps:

[0020] Step (1): Place the shell and plug on the ground or workbench, assemble the shaped charge consisting of the auxiliary charge, the main charge and the active charge shroud on the shell, and conduct the test with the plug and the active charge shroud in contact (zero distance);

[0021] Step (2): Change the distance between the active drug liner and the stopper between 0 and 5 mm, and repeat the test in step (1);

[0022] Step (3): Perform electron microscopy on the active drug-type shields obtained from different distance tests to obtain the microstructure evolution process inside the sample after different deformation stages; perform electron backscattering on the active drug-type shields obtained from different distance tests to obtain the material grain morphology at different deformation stages.

[0023] The shaped charge structure designed in this invention is simple, has a mature processing technology, and is low in cost. After the secondary charge is detonated, it will ignite the main charge. The detonation wave generated by the main charge, which has a high detonation velocity and detonation pressure, further collapses the active charge liner. The active charge liner under extreme loading conditions is recovered by plugs placed at different distances below it. The plugs, which have low strength but good toughness, ensure the collapse morphology of the liner, thus effectively "freezing" the collapse process of the liner under explosive loading conditions. Further electron backscattering characterization can obtain the material grain change characteristics, thereby improving the grain morphology of the material through additives, increasing the annealing temperature, etc. The application of a liner with preferentially arranged columnar grains can improve the jet forming effect.

[0024] The significant advantages of this invention compared to existing technologies are:

[0025] (1) The present invention achieves “freezing” of the shaped charge liner at typical moments by placing recovery plugs at different distances below the liner while ensuring normal collapse conditions;

[0026] (2) By placing a plug that fits into the shaped charge liner, the present invention can achieve the “freezing” recovery of the active material of the shaped charge liner structure under explosive loading conditions;

[0027] (3) The present invention uses copper, aluminum or rubber structures to recycle the target, which is simple in structure and low in cost;

[0028] (4) The shaped charge designed in this invention is easy to operate and safe and reliable. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the shaped charge freezing device of the present invention.

[0030] Figure 2 This is a schematic diagram of the active pharmaceutical ingredient cover in this invention.

[0031] Figure 3 This is a schematic diagram of the plug block in this invention.

[0032] Figure 4 This is a schematic diagram showing the state of the explosive freezing and recovery shaped charge liner material in the shaped charge structure of this invention; wherein (a) is a state diagram of the shaped charge liner and plug when the distance between the generatrix of the frustum section and the inner surface of the conical active shaped charge liner is 0mm; (a') is a back view of the shaped charge liner when the distance between the generatrix of the frustum section and the inner surface of the conical active shaped charge liner is 0mm; (b) is a state diagram of the shaped charge liner and plug when the distance between the generatrix of the frustum section and the inner surface of the conical active shaped charge liner is 1mm; and (b') is a back view of the shaped charge liner when the distance between the generatrix of the frustum section and the inner surface of the conical active shaped charge liner is 1mm. (c) is a back view of the shaped charge liner when the distance between the truncated cone section generatrix and the inner surface of the conical active shaped charge liner is 3mm. (c') is a back view of the shaped charge liner when the distance between the truncated cone section generatrix and the inner surface of the conical active shaped charge liner is 3mm. (d) is a back view of the shaped charge liner when the distance between the truncated cone section generatrix and the inner surface of the conical active shaped charge liner is 5mm. (d') is a back view of the shaped charge liner when the distance between the truncated cone section generatrix and the inner surface of the conical active shaped charge liner is 5mm.

[0033] Figure 5 This is a schematic diagram of the microscopic analysis of the recovered sample in this invention.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1-Sub-drug column, 2-Main drug column, 3-Active drug form shroud, 4-Plug, 5-Shell. Detailed Implementation

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

[0037] This invention provides a shaped charge "freezing" device for recovering the material of a shaped charge in a state of collapse. Under loading conditions of high temperature, high pressure, and high strain rate, the device achieves "freezing" recovery of the shaped charge material under extreme loading conditions by placing a plug structure with good toughness and low strength under the shaped charge.

[0038] like Figure 1 As shown, the shaped charge "freezing" device of the present invention includes: a secondary charge 1, a main charge 2, an active charge shroud 3, a plug 4, and a shell 5;

[0039] The main charge 2 is cylindrical in shape, with grooves on its upper and lower ends that match the outer surfaces of the auxiliary charge and the active charge liner. The main charge 2 typically uses high-velocity, high-pressure explosives, such as B explosive. It is generally press-fitted into the aforementioned structure using a mold. The length-to-diameter ratio of the main charge 2 is approximately 1 to 1.3, and it is detonated by the auxiliary charge 1.

[0040] The auxiliary explosive charge 1 is cylindrical, coaxial with the main explosive charge 2, and tightly fitted into the upper groove of the main explosive charge 2. The auxiliary explosive charge 1 generally uses a low-velocity, low-pressure explosive, such as TNT. It is typically press-fitted into the structure described above using a mold, and employs a single-point center initiation method.

[0041] The active pharmaceutical ingredient shroud 3 is a hollow cone shape with one open end, such as... Figure 2 As shown. The active drug template 3 is made of active materials, such as PTFE / Al, Al / Ni, or other active energetic mixtures, amorphous alloys, or high-entropy alloys. The conical active drug template 3 is generally a uniform wall thickness template, coaxial with the main drug column 2, and its outer surface is tightly fitted with the groove surface at the lower end of the main drug column. The lower end surface of the active drug template 3 is flush with the lower end surface of the main drug column 2.

[0042] The shell 5 is a cylindrical tube with openings at both ends. The shell 5 is coaxially assembled with the main drug cartridge 2. The upper surface of the shell 5 is in close contact with the active drug liner 3 and the lower surface of the main drug cartridge 2, used to adjust the distance between the stopper 4 and the active drug liner 3 to recover materials under different collapse states. The inner diameter of the shell 5 is greater than or equal to the outer diameter of the stopper 4, but smaller than the outer diameter of the active drug liner 3. The shell 5 is made of low-density metallic materials or high-molecular non-metallic materials, such as aluminum or nylon.

[0043] The stopper 4 is a combination of a frustum and a cylinder. The generatrix of the frustum of the stopper 4 is parallel to the generatrix of the active pharmaceutical ingredient shroud 3 and is coaxially assembled with the main drug cartridge 2. The lower bottom surface of the stopper 4 is flush with the lower end surface of the shell 5. Specifically, when the distance between the generatrix of the frustum of the stopper 4 and the generatrix of the active pharmaceutical ingredient shroud 3 is 0, the height of the cylindrical section of the stopper 4 is 0, enabling "freezing" recovery of the active pharmaceutical ingredient shroud 3 under extreme loading conditions. When the distance between the generatrix of the frustum of the stopper 4 and the generatrix of the active pharmaceutical ingredient shroud 3 is greater than 0, the height of the cylindrical section of the stopper 4 is greater than or equal to the distance between the upper surface of the frustum of the stopper 4 and the top of the active pharmaceutical ingredient shroud 3, enabling "freezing" of the active pharmaceutical ingredient shroud 3 at typical collapse moments. The stopper 4 is made of a material with good toughness and low strength, distinct from the composition of the active pharmaceutical ingredient shroud 3, such as copper or rubber.

[0044] Example 1

[0045] In this embodiment, the main charge 2 is formed by molding and pressing. The main charge 2 has a diameter of 50 mm, a length-to-diameter ratio of 1.3, and a mass of 154.4 g. The main charge 2 is made of 8701 explosive. The auxiliary charge 1 is coaxially filled into the groove on the upper end face of the main charge 2. It is made of TNT explosive with a slightly lower detonation velocity than 8701 explosive and is tightly bonded to the main charge 2 with shellac. The auxiliary charge has a size of Φ15*7. The active charge liner 3 is tightly bonded to the groove at the lower end of the main charge 2 with shellac. The conical active charge liner 3 is made of Al / Ni through high-temperature sintering. The liner has a diameter of 45.6 mm, a wall thickness of 1.6 mm, and a mass of 59.8 g. The active charge liner 3 is tightly bonded to the lower bottom surface of the main charge 2 and the upper end face of the shell 5. The shell 5 is a nylon round tube with openings at the top and bottom, an inner diameter of 44.5 mm, and a thickness of 1.5 mm. The plug 4 is flush with the lower end face of the shell 5 and consists of a cylindrical section and a frustum section. The shape of the frustum section is consistent with the inner surface shape of the conical active drug cover 3; the plug 4 is made of copper. Figure 4 (a) to (d) show schematic diagrams of the "freezing" effect when the distance between the generatrix of the frustum segment and the inner surface of the conical active pharmaceutical ingredient shroud 3 is 0 mm, 1 mm, 3 mm, and 5 mm, respectively. The recovered materials were characterized using scanning electron microscopy and electron backscatter diffraction to obtain their microstructure and grain characteristics, such as... Figure 5 As shown.

Claims

1. A device for freezing shaped charge materials in a state of compressing active pharmaceutical ingredient, characterized in that, It includes a secondary drug column (1), a main drug column (2), an active drug form shroud (3), a plug (4), and multiple cylindrical shells (5) of the same diameter but different heights. The main charge (2) is cylindrical in shape. The upper end of the main charge (2) is equipped with a secondary charge (1) for detonating the main charge (2). The lower part of the main charge (2) is a frustum-shaped groove. The frustum-shaped groove is equipped with an active charge liner (3) with a matching shape. The inner diameter of the shell (5) is smaller than the diameter of the main charge and larger than the inner diameter of the large end of the active charge liner (3). The plug is composed of a frustum section and a cylindrical section, and the shape of the frustum section matches the shape of the active charge liner (3). The shell (5) is placed on the ground or workbench, the plug (4) is placed inside the shell (5), and one end of the cylindrical section is placed on the ground or workbench inside the shell. By changing the shell of different heights, the distance between the plug (4) and the active drug liner (3) can be adjusted. Multiple tests are conducted with only different distances, so as to realize the state freezing and recovery at different times during the jet forming process of the active drug liner material.

2. The shaped charge freezing device according to claim 1, characterized in that, The auxiliary charge (1), the main charge (2), the active charge shroud (3), the plug (4) and the shell (5) are arranged coaxially. The auxiliary charge (1) uses low detonation velocity and low detonation pressure explosive, and the main charge (2) uses high detonation velocity and high detonation pressure explosive.

3. The shaped charge freezing device according to claim 2, characterized in that, The auxiliary explosive (1) and the main explosive (2) are formed by mold pressing. The auxiliary explosive (1) adopts a single-point center initiation method. The auxiliary explosive (1) uses TNT explosive, and the main explosive (2) uses 8701 explosive.

4. The shaped charge freezing device according to claim 3, characterized in that, The plug (4) is made of a material with a different composition from the active drug liner (3) and with lower strength and better toughness than the active drug liner; The shell (5) is made of low-density metal or polymer materials.

5. The shaped charge freezing device according to claim 4, characterized in that, The plug (4) is made of copper, aluminum or rubber; the shell (5) is made of aluminum, nylon or polycarbonate.

6. The shaped charge freezing device according to claim 5, characterized in that, The active drug molded cover is made by cold pressing, high-temperature sintering or high-temperature melting of active materials; the active materials used in the active drug molded cover are metal mixtures, amorphous alloys or high-entropy alloys.

7. The shaped charge freezing device according to claim 6, characterized in that, The active drug liner is a drug liner with equal or variable wall thickness; the active drug liner (3) is conical, tulip-shaped or trumpet-shaped; the length-to-diameter ratio of the main drug column (2) is 1~1.

3.

8. The shaped charge freezing device according to claim 7, characterized in that, The main drug column (2), the auxiliary drug column (1), the outer surface of the active drug type cover (3), and the end face of the shell (5) are coated with insect glue.

9. A method for state freezing using the apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Place the shell (5) and plug (4) on the ground or workbench, assemble the shaped charge consisting of the auxiliary charge (1), the main charge (2) and the active charge shroud (3) onto the shell, and conduct the test with the plug (4) and the active charge shroud (3) in contact (0 distance); Step 2: Change the distance between the inner diameter generatrix of the active pharmaceutical ingredient cover (3) and the generatrix of the plug (4) between 0 and 5 mm, and repeat the test in Step 1; Step 3: Perform electron microscopy on the active drug-type shield (3) obtained from different distance tests to obtain the microstructure evolution process inside the sample after different deformation stages; perform electron backscattering on the active drug-type shield (3) obtained from different distance tests to obtain the material grain morphology at different deformation stages.

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