An energetic composite charge liner for shaped charge warhead and its preparation method

Abstract

The present invention provides an energetic composite liner for a shaped charge warhead and a method for preparing the same. The liner comprises a metal substrate, a metal powder layer disposed on the liner metal substrate. The metal powder is cold-sprayed onto the metal substrate to form the metal powder layer. The metal powder can be aluminum powder, nickel powder, titanium powder, zirconium powder, or iron powder. The preparation method comprises sandblasting, cleaning, and spraying the metal powder onto the outer conical surface of the liner metal substrate to produce the energetic composite liner. The energetic composite liner for a shaped charge warhead provided by the present invention can release a large amount of energy through a chemical reaction of the liner's active elements while ensuring high penetration and pore expansion when damaging a target. This results in a high aftereffect of damage, enhanced lethality, and combustion effects.

Description

Technical Field

[0001] The present invention relates to the technical field of penetrating shaped charge warheads, and in particular to an energetic composite charge liner for a shaped charge warhead and a preparation method thereof. Background Art

[0002] With the development of military technology, ammunition and weapons are primarily developing in the direction of "long-range attack, precision guidance, and efficient destruction." As the ultimate link and goal of destroying enemy military targets, efficient destruction places more stringent demands on improving its destruction effectiveness. As the core component of the penetrating shaped charge warhead, the liner rapidly closes toward its axis under the concentrated high pressure of the shaped charge's detonation products. The metal on the liner's inner wall is continuously squeezed, forming a high-speed penetrator moving forward, requiring "deep penetration, large pore expansion, and high aftereffect." Traditional shaped charge warhead liners mostly use inert liner materials. When striking high-value military targets such as tanks, armored vehicles, aircraft, ships, and deep underground, they primarily rely on chemically generated concentrated kinetic energy to achieve armor penetration and other effects. Liners of different materials and configurations achieve different penetration and pore expansion effects, but the destruction effect is monotonous, and the destruction capability needs further optimization.

[0003] Existing document CN202117644U proposes a secondary explosive energy-releasing liner. This involves spraying or pressing a layer of energetic material onto the outer layer of the deep-penetrating perforating liner, creating a composite liner. Alternatively, an energetic material can be added to the metal powder of the deep-penetrating liner in a specific proportion. This is then formed through pressing and drying processes to create a special liner. The secondary explosive energy-releasing liner is then pressed together with the perforating charge shell and explosive using a tooling die to form a secondary explosive energy-releasing perforating charge. However, this liner is only suitable for perforating operations in oil and gas production.

[0004] As an energetic composite charge liner for shaped charge warheads, the key to ensuring high damage aftereffects is to form a stable and uniform metal jet and ensure the stability of the pestle during use. However, the closest existing energetic composite charge liner (similar to the aforementioned secondary explosion energy-releasing charge liner) cannot ensure the stability and uniformity of the metal jet during the armor-piercing process, and it is difficult to ensure the stability of the pestle. Summary of the Invention

[0005] At least in response to the technical problems mentioned in the background technology, the purpose of the present invention is to provide an energetic composite charge liner for a shaped charge warhead and a preparation method thereof.

[0006] The present invention adopts the following technical solutions.

[0007] An energetic composite charge liner for a shaped charge warhead comprises a liner metal substrate, a metal powder layer is provided on the liner metal substrate, and the metal powder is sprayed on the metal substrate by cold spraying to form the metal powder layer. The metal powder is aluminum powder, nickel powder, titanium powder, zirconium powder or iron powder, and the particle size of the metal powder is 15 to 45 μm.

[0008] In order to further improve the high damage aftereffect of the energetic composite liner, the metal powder is embedded in the concave portion of the outer cone surface of the metal substrate of the liner.

[0009] Preferably, the recessed portions are a plurality of arc-shaped pits arranged at intervals or a plurality of strip-shaped grooves arranged at intervals.

[0010] To further enhance the high-damage aftereffect of the energetic composite liner, a covering layer is provided around the metal powder. The covering layer is made of the same material as the liner's metal matrix and is fused and bonded to the liner's metal matrix and the metal powder layer. Furthermore, the recess is a strip-shaped groove located at the bottom of the liner, with its bottom flush with the liner's open end. The height difference between the top and bottom of the recess is 1 / 3 of the liner's total height. The depth of the recess gradually decreases from the bottom to the top, approaching zero at the top and no more than 2 / 3 of the thickness of the liner's metal matrix at the bottom. By adopting such a scheme, the covering layer is clad on the non-concave area on the metal substrate of the charge liner and is clad on the metal powder layer. The metal powder layer is embedded in and metallurgically bonded to the metal substrate of the charge liner. In the process of forming the metal jet and the pestle of the composite charge liner, the front of the metal substrate forms a jet, and the rear of the metal substrate and the covering layer together serve as a covering surface layer to cover the metal powder layer and form the pestle of the metal jet. This not only ensures that the formed jet is continuous, uniform and stable, but also ensures that the energetic metal powder will not be lost under the impact of the explosive detonation wave. The covering layer can also prevent the active energetic elements from reacting prematurely, and protect the active energetic metal powder. More importantly, it can effectively prevent the pestle from separating / breaking from the metal jet.

[0011] Preferably, the wall thickness of the metal substrate of the liner is not greater than 2 mm.

[0012] The present invention also provides a method for preparing the aforementioned energetic composite charge liner for a shaped charge warhead, the steps comprising:

[0013] Step 1: First, sandblast the outer conical surface of the metal substrate of the liner, and then clean the metal substrate of the liner;

[0014] Step 2: Use cold spraying equipment to spray metal powder on the outer cone surface of the metal substrate of the liner to obtain an energetic composite liner.

[0015] Preferably, the corundum used for sandblasting has a particle size of 24-60 mesh and a blasting air pressure of 8.5-8.7 MPa. The cold spraying process parameters are: a spraying rate of 1-2 kg / h, a metal powder particle flow velocity of 500-800 m / s, nitrogen at a pressure of 1-1.5 MPa for spraying, and a compressed gas heating temperature of 300-600°C. In the present invention, the combination of the aforementioned specific particle size of corundum and the specific blasting air pressure ensures that a suitable concave pit is formed on the outer conical surface of the metal substrate of the liner. Excessive blasting air pressure can cause the corundum to adhere, while insufficient blasting air pressure can result in a shallow concave pit.

[0016] In order to better ensure the stability and uniformity of the metal jet, sandblasting and cold spraying are both carried out in a closed space. The metal substrate of the liner is sleeved and tightly attached to the standard conical mold. The outer cone of the standard conical mold is the same shape as the inner cone of the metal substrate of the liner. The standard conical mold is installed on a rotating platform. The axis of the standard conical mold, the axis of the metal substrate of the liner, and the center line of the rotating platform coincide. The working areas of the multiple nozzles of the sandblasting equipment and the multiple nozzles of the cold spraying equipment cover the entire area to be sprayed on the metal substrate of the liner, and each nozzle is perpendicular to the outer cone of the metal substrate of the liner. During the sandblasting and cold spraying process, each nozzle is fixed, and the rotating platform, the standard conical mold and the metal substrate of the liner rotate synchronously.

[0017] Furthermore, during the sandblasting and cold spraying processes, a constant pressure is maintained within the enclosed space. During sandblasting, this constant pressure is consistent with the air source pressure, while during cold spraying, it is consistent with the compressed gas pressure. This approach ensures that the inner conical surface of the liner metal matrix does not deform or bulge inward during the manufacturing process, maintaining the dimensional accuracy and surface quality of the inner conical surface of the liner metal matrix.

[0018] Preferably, the thickness of the metal powder layer on the metal substrate of the liner is no more than 1.5 mm.

[0019] Beneficial effects: The energetic composite charge liner for the shaped charge warhead provided by the present invention can release a large amount of energy through chemical reaction of the active elements (energetic metal powder) of the charge liner while ensuring large penetration and large pore expansion when destroying the target, thereby having a high damage aftereffect and increasing the killing and combustion effects; under the action of high-temperature and high-pressure detonation products, a high-speed flying metal shaped charge penetrator carrying active units can be formed, achieving the purposes of large penetration, large pore expansion and high aftereffect; the active elements on the metal matrix of the charge liner can undergo chemical reaction as the metal jet penetrates into the target, releasing a large amount of chemical energy, which is conducive to igniting fuel and detonating ammunition; more importantly, it can ensure the stability and uniformity of the metal jet formed by the composite charge liner, and can effectively prevent the pestle from separating / breaking from the metal jet.

[0020] The preparation method of the present invention can effectively compound existing difficult-to-combine charge liners (such as Cu-Zr, Ta-Al, Ti-Al, etc.) with active materials, accurately control the thickness of the charge liner, and has the advantages of high production efficiency, low production cost, low energy consumption, and recyclable materials. It can also achieve adjustable type and thickness of active materials on the metal substrate of the charge liner and mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the metal substrate of the charge liner in the embodiment;

[0022] Figure 2 Schematic diagram of the preparation process of the energetic composite liner in Example 3;

[0023] Figure 3 This is a schematic cross-sectional view of the energetic composite liner in Example 4. Implementation Method

[0024] The following is a clear and complete description of the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention. Example

[0025] A composite energetic liner for a shaped charge warhead comprises a liner metal substrate, the liner metal substrate being a pure copper liner (produced by a precision cold extrusion process), a metal powder layer being provided on the outer conical surface of the liner metal substrate, the metal powder being sprayed on the metal substrate by cold spraying to form a metal powder layer having a thickness of 1.5 mm, the metal powder being pure activated aluminum powder, the metal powder having a particle size of 15 to 30 μm, and a portion of the metal powder being embedded in a recessed portion of the outer conical surface of the liner metal substrate, the recess being an arc-shaped pit formed by the sandblasting process in this example.

[0026] The method for preparing an energetic composite charge liner for a shaped charge warhead in this embodiment comprises the following steps:

[0027] Step 1: First, sandblast the outer conical surface of the metal substrate of the liner, and then clean the metal substrate of the liner (degreasing and removing dust);

[0028] Step 2: Using a cold spraying device, the nozzle assembly of the cold spraying device is mounted on a six-axis spraying robot, and metal powder is sprayed on the outer conical surface of the metal substrate of the liner to form a metal powder layer to obtain an energetic composite liner;

[0029] Among them, the sandblasting and cold spraying treatments are both carried out in a closed space, and the metal substrate of the liner is placed and tightly attached to the standard conical mold. The outer cone surface of the standard conical mold has the same shape as the inner cone surface of the metal substrate of the liner.

[0030] The diamond grain size used for sandblasting is 24±4 mesh, and the sandblasting gas source pressure is 8.6 MPa. The cold spraying process parameters are: nozzle movement speed 1 mm / s, spraying speed 1 kg / h, metal powder particle flow speed 500 m / s, compressed gas for spraying uses nitrogen with a pressure of 1.5 MPa, and the compressed gas heating temperature is 350°C. Example

[0031] A composite energetic liner for a shaped charge warhead comprises a liner metal substrate, the liner metal substrate being a pure copper liner (produced by a precision cold extrusion process), a metal powder layer being provided on the liner metal substrate, the metal powder being sprayed on the metal substrate by cold spraying to form a metal powder layer, the metal powder layer having a thickness of 1 mm, the metal powder being a mixture of pure active aluminum powder and pure active nickel powder (the volume ratio of pure active aluminum powder to pure active nickel powder being 2:1), the aluminum powder having a particle size of 20 to 35 μm, and the nickel powder having a particle size range of 15 to 30 μm, the metal powder being embedded in a concave portion of the outer conical surface of the liner metal substrate, the concave portion being an arc-shaped pit formed by the sandblasting process in this example.

[0032] The method for preparing an energetic composite charge liner for a shaped charge warhead in this embodiment comprises the following steps:

[0033] Step 1: First, sandblast the outer conical surface of the metal substrate of the liner, and then clean the metal substrate of the liner (degreasing and removing dust);

[0034] Step 2: Use cold spray equipment. The nozzle assembly of the cold spray equipment is installed on a six-axis spray robot. Metal powder (a mixture of pure active aluminum powder and pure active nickel powder) is sprayed on the outer conical surface of the metal substrate of the charge liner to form a metal powder layer to obtain an energetic composite charge liner.

[0035] Among them, the sandblasting and cold spraying treatments are both carried out in a closed space, and the metal substrate of the liner is placed and tightly attached to the standard conical mold. The outer cone surface of the standard conical mold has the same shape as the inner cone surface of the metal substrate of the liner.

[0036] The diamond grain size used for sandblasting is 36±3 mesh, and the air source pressure used for sandblasting is 8.5 MPa. The cold spraying process parameters are: nozzle movement speed 1.5 mm / s, spraying speed 1.2 kg / h, metal powder particle flow speed 600 m / s, compressed gas for spraying uses nitrogen with a pressure of 1.2 MPa, and the compressed gas heating temperature during cold spraying is 420°C. Example

[0037] A composite energetic liner for a shaped charge warhead comprises a liner metal substrate, the liner metal substrate being a pure copper liner (produced by a precision cold extrusion process), a metal powder layer being provided on the liner metal substrate, the metal powder being sprayed on the metal substrate by cold spraying to form a metal powder layer having a thickness of 0.8 mm, the metal powder being pure active aluminum powder having a particle size of 15-25 μm, the metal powder being embedded in a recessed portion of the outer conical surface of the liner metal substrate, the recess being an arc-shaped pit formed by a sandblasting process in this example; a covering layer being clad on the surface of the metal powder layer, the covering layer material being the same as that of the liner metal substrate.

[0038] The method for preparing an energetic composite charge liner for a shaped charge warhead in this embodiment comprises the following steps:

[0039] Step 1, combine Figure 1 、 Figure 2 and Figure 3 As shown, the liner metal substrate 4 is first placed on the standard conical mold 3, and then covered with a cover 6. The cover 6 has a pressure relief hole, and the inner cavity of the cover 6 is a closed space 9. A pipe joint 8 is provided on the top of the cover 6, and the pipe joint 8 is connected to an external compressed air source. The outer cone of the standard conical mold 3 has the same shape as the inner cone of the liner metal substrate 4. The standard conical mold 3 is mounted on a rotating platform 2, which is connected to a drive mechanism 1. The axis of the standard conical mold 3, the axis of the liner metal substrate 4, and the centerline of the rotating platform 2 coincide. The nozzle assemblies of the sandblasting equipment and the cold spraying equipment are all installed in the closed space 9. The working areas of the multiple nozzles 7 of the sandblasting equipment and the multiple nozzles 5 of the cold spraying equipment cover the entire area to be sprayed on the liner metal substrate 4. Each nozzle is perpendicular to the outer cone of the liner metal substrate 4, and the vertical distance between the nozzle orifice and the surface of the liner metal substrate 4 is 5-8 mm. During the sandblasting and cold spraying process, the driving mechanism 1 drives the rotating platform 2 to rotate, the nozzles are fixed, and the rotating platform 2, the standard conical mold 3 and the liner metal substrate 4 rotate synchronously. The subsequent sandblasting and cold spraying steps are all carried out in the closed space 9.

[0040] Then, the compressed air source corresponding to the pipe joint 8 is opened (the pressure of the compressed air source is controlled to be 0.48±0.1MPa, using nitrogen), and the outer conical surface of the metal substrate 4 of the liner is sandblasted. The grain size of the corundum used for sandblasting is 20±2 mesh, and the air source pressure used for sandblasting is 8.55MPa;

[0041] Then close the pipe joint 8, connect the compressed air source and sandblasting equipment, take out the liner metal substrate 4 and clean it (degreasing and removing dust);

[0042] Step 2: The cleaned liner metal substrate 4 is then placed on the standard conical mold 3. The compressed air source connected to the pipe joint 8 is opened, and then the cold spray equipment is turned on to spray metal powder on the outer conical surface of the liner metal substrate 4 (spraying rate 1 kg / h, metal powder particle flow velocity 500 m / s, compressed gas for spraying is nitrogen with a pressure of 1.5 MPa, and the compressed gas heating temperature is 400°C) to form a metal powder layer;

[0043] Step 3: Then, the metal base 4 of the charge liner with the metal powder layer is taken out, and a layer of copper powder is melt-coated on the outer wall of the metal powder layer to form a covering layer to obtain an energetic composite charge liner.

[0044] In this embodiment, during the sandblasting and cold spraying process, the aforementioned specific constant pressure state is basically maintained in the enclosed space 9, which can ensure that the inner conical surface of the metal substrate 4 of the liner does not deform or bulge inward during the preparation process, and can ensure that the smoothness of the inner conical surface of the metal substrate 4 of the liner does not change.

[0045] In this embodiment, the covering layer is clad on the non-concave area on the metal base 4 of the charge liner and is clad on the metal powder layer. The metal powder layer is embedded and metallurgically bonded to the metal base 4 of the charge liner. In the process of forming the metal jet and the pestle of the composite charge liner, the front of the metal base forms a jet, and the rear of the metal base and the covering layer together serve as a covering surface layer to cover the metal powder layer and become the pestle of the metal jet. This not only ensures that the formed jet is continuous, uniform and stable, but also ensures that the energetic metal powder will not be lost under the impact of the explosive detonation wave. The covering layer can also prevent the active energetic elements from reacting prematurely, thereby protecting the active energetic metal powder. Example

[0046] An energetic composite charge liner for a shaped charge warhead comprises a charge liner metal substrate (main body thickness is 2 mm), the charge liner metal substrate adopts a pure copper charge liner (produced by a precision cold extrusion process), a metal powder layer is provided on the charge liner metal substrate, the metal powder is sprayed on the metal substrate by cold spraying to form a metal powder layer, the surface of the metal powder layer is clad with a covering layer, the covering layer material is the same as the charge liner metal substrate material; the maximum thickness of the metal powder layer is 1 mm, the metal powder is a mixture of pure active aluminum powder and pure active nickel powder, the particle size of the aluminum powder is 20-35 μm, and the particle size range of the nickel powder is 15-3 0μm, the metal powder is embedded in the concave portion of the outer cone surface of the metal matrix of the liner, the concave portion is a plurality of pre-processed strip grooves (obtained by tool processing), the spacing between adjacent strip grooves is 5mm, the concave portion is located at the lower part of the liner, the bottom end of the concave portion is flush with the open end of the liner, and the height difference between the top end of the concave portion and the bottom end of the concave portion is 1 / 3 of the total height of the liner, and the depth of the concave portion gradually decreases from the bottom end to the top end of the concave portion, the depth of the top end of the concave portion is close to zero, and the depth of the bottom end of the concave portion is about 1 / 2 of the thickness of the metal matrix of the liner; the preparation method of the energetic composite liner for the shaped charge warhead in this embodiment is the same as that in Example 3. In this embodiment, the covering layer is clad on the non-concave area on the metal substrate of the charge liner and is clad on the metal powder layer. The metal powder layer is embedded in and metallurgically bonded to the metal substrate of the charge liner. In the process of forming the metal jet and the pestle of the composite charge liner, the front of the metal substrate forms a jet, and the rear of the metal substrate and the covering layer together serve as a covering surface layer to cover the metal powder layer and form the pestle of the metal jet. This not only ensures that the formed jet is continuous, uniform and stable, but also ensures that the energetic metal powder will not be lost under the impact of the explosive detonation wave. The covering layer can also prevent the active energetic elements from reacting prematurely and protect the active energetic metal powder. More importantly, combined with this depth-gradient strip groove, it can also effectively prevent the pestle from separating / breaking from the metal jet.

[0047] For the energetic composite charge liner for the shaped charge warhead in the embodiment, the static explosion test found that there was obvious bright light in the process of the penetrator damaging the homogeneous armor steel target and the No. 45 steel target, and there were black burn marks on the entrance hole surface of the steel target; for the energetic composite charge liner for the shaped charge warhead in Example 3 and Example 4, the shooting test (the fired projectile flew freely and fell freely into the water at room temperature without penetrating the object) found that the formed metal jet was smooth and round, and the formed pestle was a sandwich structure (the outermost layer was a ring-shaped body formed by the metal matrix of the charge liner, the middle layer was a ring-shaped body formed by the metal powder layer, and the inner layer was a column formed by the covering layer).

[0048] The energetic composite charge liner for a shaped charge warhead provided by the present invention can release a large amount of energy through chemical reactions of the active elements (energetic metal powder) in the charge liner while ensuring large penetration and large pore expansion when destroying a target, thereby having a high damage aftereffect and increasing the killing and combustion effects; under the action of high-temperature and high-pressure detonation products, a high-speed flying metal shaped charge penetrator carrying active units can be formed, achieving the purposes of large penetration, large pore expansion and high aftereffect; the active elements on the metal matrix of the charge liner can undergo chemical reactions as the metal jet penetrates into the target, releasing a large amount of chemical energy, which is conducive to igniting fuel and detonating ammunition; more importantly, the stability and uniformity of the metal jet formed by the composite charge liner can be ensured, and the separation / fracture of the pestle and the metal jet can be effectively prevented. The preparation method of the present invention can effectively compound existing difficult-to-combine charge liners (such as Cu-Zr, Ta-Al, Ti-Al, etc.) with active materials, accurately control the thickness of the charge liner, and has the advantages of high production efficiency, low production cost, low energy consumption, and recyclable materials. It can also achieve adjustable type and thickness of active materials on the metal substrate of the charge liner and mass production.

Claims

1. An energetic composite liner for a shaped charge warhead, comprising a liner metal substrate, characterized in that: A metal powder layer is provided on the metal substrate of the liner. The metal powder is sprayed on the metal substrate by cold spraying to form a metal powder layer. The metal powder is aluminum powder, nickel powder, titanium powder, zirconium powder or iron powder, and the particle size of the metal powder is 15~45μm; the metal powder is embedded in the recess of the outer cone surface of the metal substrate of the liner; the wall thickness of the metal substrate of the liner is not more than 2mm; the recess is a strip groove, the recess is located at the lower part of the liner, the bottom end of the recess is flush with the open end of the liner, and the height difference between the top end of the recess and the bottom end of the recess is 1 / 3 of the total height of the liner, and the depth of the recess gradually decreases from the bottom end to the top end of the recess, the depth of the recess is close to zero, and the depth of the bottom end of the recess is not more than 2 / 3 of the thickness of the metal substrate of the liner.

2. The energetic composite liner according to claim 1, characterized in that: The concave portions are a plurality of arc-shaped pits arranged at intervals or a plurality of strip-shaped grooves arranged at intervals.

3. The energetic composite liner according to claim 2, characterized in that: A covering layer is arranged on the periphery of the metal powder layer. The covering layer material is the same as the metal matrix material of the liner. The covering layer is clad and bonded to the metal matrix of the liner and the metal powder layer.

4. The method for preparing an energetic composite liner for a shaped charge warhead according to any one of claims 1 to 3, characterized in that the steps include: Step 1: First, sandblast the outer conical surface of the metal substrate of the liner, and then clean the metal substrate of the liner; Step 2: Use cold spraying equipment to spray metal powder on the outer cone surface of the metal substrate of the liner to obtain an energetic composite liner.

5. The preparation method according to claim 4, characterized in that: The grain size of the corundum used for sandblasting is 24-60 mesh, and the air source pressure used for sandblasting is 8.5-8.7 MPa. The cold spraying process parameters are: spraying speed 1-2 kg / h, metal powder particle flow velocity 500-800 m / s, compressed gas for spraying uses nitrogen with a pressure of 1-1.5 MPa, and compressed gas heating temperature 300-600 °C.

6. The preparation method according to claim 5, characterized in that: Both sandblasting and cold spraying are carried out in a closed space. The metal base of the liner is sleeved and tightly attached to the standard conical mold. The outer cone of the standard conical mold has the same shape as the inner cone of the metal base of the liner. The standard conical mold is installed on a rotating platform. The axis of the standard conical mold, the axis of the metal base of the liner, and the center line of the rotating platform coincide. The working areas of the multiple nozzles of the sandblasting equipment and the multiple nozzles of the cold spraying equipment cover the entire area to be sprayed on the metal base of the liner, and each nozzle is perpendicular to the outer cone of the metal base of the liner. During the sandblasting and cold spraying process, each nozzle is fixed, and the rotating platform, the standard conical mold and the metal base of the liner rotate synchronously.

7. The preparation method according to claim 6, characterized in that: During the sandblasting and cold spraying processes, a constant pressure state is maintained in the enclosed space. The constant pressure in the sandblasting state is consistent with the gas source pressure, and the constant pressure in the cold spraying state is consistent with the compressed gas pressure.

8. The preparation method according to claim 7, characterized in that: The thickness of the metal powder layer on the metal substrate of the liner shall not exceed 1.5 mm.

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