A high-performance composite material bullet shell, a processing method and a bullet using the bullet shell

Abstract

The application discloses a high-performance composite material bullet shell, a processing method and a bullet using the bullet shell, wherein the material of the high-performance composite material bullet shell is a composite material, the composite material comprises a thermosetting or thermoplastic base material and a fiber material, and the fiber material comprises at least one of basalt fiber, polyimide fiber and aramid fiber. The high-performance composite material bullet shell of the application adopts lightweight high-strength basalt fiber composite material, polyimide fiber composite material and aramid fiber composite material to replace the original bullet shell, so that the phenomenon of shell burst, shell rupture and the like of the plastic shell during bullet shooting is eliminated, the overall weight of the product is reduced while the bullet shell use performance is met, and the purpose of lightening is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bullet shell, in particular to a high-performance composite material bullet shell, a processing method and a bullet using the bullet shell. BACKGROUND

[0002] A bullet is composed of a bullet head, a propellant, a primer, and a bullet shell. Traditional bullets are simple in style and single in function, and have a large number of manufacturing processes, which makes the bullet forming period long. Traditional bullet shells are mostly made of brass and steel as raw materials, which are not only expensive but also heavy. The bullet shell accounts for about half of the total weight of the bullet. The metal bullet shell, especially the steel bullet shell, has poor reusability, which causes a great waste and cannot meet the actual needs of modern combat scale.

[0003] The composite material bullet shell can not only reduce the cost of the bullet, but also effectively reduce the weight of the bullet shell and reduce material waste, which conforms to the environmental protection and energy saving strategy and resource strategy of "plastic instead of steel".

[0004] The development of the composite material bullet shell has made certain progress, but its application is not mature enough and still has some problems worth exploring, mainly in the following aspects.

[0005] 1) High cost. On the one hand, although the bullet shell of the bullet is made of plastic, the firing base is still made of brass. On the other hand, the forming material of some bullets is completely replaced by composite material instead of metal material. In order to meet the use performance, the forming material mostly used is engineering plastic or special plastic, which is expensive and increases the cost.

[0006] 2) Safety hazard in use. The traditional ordinary bullet is made of all metal materials or the base is made of metal materials, which ensures that the bullet does not appear phenomena such as burst and rupture when shooting. However, after using composite material instead of metal material, the bullet shell is easy to burst or rupture when shooting, thereby causing certain harm to the user's body.

[0007] Therefore, we propose a new type of high-performance composite material bullet shell to solve the above problems. SUMMARY

[0008] The purpose of the present application is to provide a high-performance composite material bullet shell, a processing method and a bullet using the bullet shell.

[0009] The present application is implemented as follows:

[0010] In a first aspect, the present application provides a high-performance composite material bullet shell, the material of the bullet shell is a composite material, the composite material includes a thermosetting or thermoplastic base material and a fiber material, the fiber material includes at least one of basalt fiber, polyimide fiber and aramid fiber.

[0011] In an optional embodiment, the shell comprises a shell cylinder and an initiating hole on the shell cylinder, and a continuous pressure cylinder is arranged in the shell cylinder close to one end of the initiating hole, and the continuous pressure cylinder is a composite material.

[0012] In an optional embodiment, the base material of the continuous pressure cylinder is a liquid resin, and the mass fraction of the base material in the continuous pressure cylinder is 60-70%.

[0013] In an optional embodiment, the fiber material in the continuous pressure cylinder is a basalt fiber plain cloth or a basalt fiber twill cloth, and the areal density is 200-500 g / m 2 .

[0014] In an optional embodiment, the molding material in the shell cylinder is a solid composite material.

[0015] In an optional embodiment, the volume fraction of the fiber in the shell cylinder is 30-50%.

[0016] In an optional embodiment, the shell cylinder is sequentially provided with a first shell cylinder segment, a second shell cylinder segment and a third shell cylinder segment in the direction away from the initiating hole, the wall thickness of the first shell cylinder segment, the second shell cylinder segment and the third shell cylinder segment gradually decreases, and the continuous pressure cylinder is arranged in the first shell cylinder segment.

[0017] In a second aspect, the application provides a processing method of the high-performance composite material shell as described in any one of the preceding embodiments, comprising continuous pressure cylinder molding and shell cylinder molding.

[0018] The continuous pressure cylinder is molded by molding or wet molding, the shell cylinder is molded by injection molding, and then the continuous pressure cylinder and the shell cylinder are assembled; or the continuous pressure cylinder is molded by molding or wet molding, and then the continuous pressure cylinder is used as an insert to obtain the shell by insert injection molding.

[0019] In an optional embodiment, the application comprises:

[0020] The liquid resin is applied on the surface of the basalt fiber plain cloth, and is pre-cured at 35-45℃ for 1-2h, and then is molded by molding or wet molding to obtain the continuous pressure cylinder.

[0021] The continuous pressure cylinder is used as an insert, and is integrally injection molded by insert injection molding process at 270-290℃ to obtain the high-performance composite material shell.

[0022] In a third aspect, the application provides a bullet comprising the high-performance composite material shell as described in any one of the preceding embodiments.

[0023] The application has the following beneficial effects:

[0024] The high-performance composite shell of the present application is used to eliminate the phenomena of shell burst and shell rupture of the plastic shell when the bullet is fired, and uses lightweight high-strength basalt fiber composite material, polyimide fiber composite material and aramid fiber composite material to replace the original shell, so that the overall weight of the product is reduced while the performance of the shell is met, so as to achieve the purpose of lightening.

[0025] The use of basalt fiber composite material, polyimide fiber composite material and aramid fiber composite material to make the shell can greatly leapfrog the lightweight research in the field of defense equipment: first, the weight of the product can be reduced, the weight of the user can be reduced, and the logistics pressure can be relieved; second, the material is saved, and the consumption of steel and expensive brass materials is avoided; third, the requirement for high-precision processing of copper and steel parts is avoided, the production cost is reduced, and the consistency of the ammunition can be improved by using injection molding process to ensure the precision; finally, the composite shell can ensure higher muzzle velocity, and the chamber pressure can be maintained in a higher range, which cannot be achieved by brass and other metal products. BRIEF DESCRIPTION OF DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0027] Figure 1 It is a structure schematic diagram of the continuous pressure cylinder in Example 1;

[0028] Figure 2 It is a structure schematic diagram of the shell cylinder in Example 1;

[0029] Figure 3 It is a schematic diagram of the shell after shooting in Comparative Example 1;

[0030] Figure 4 It is a stress distribution diagram of the aluminum alloy shell in Comparative Example 2 at the chamber pressure of 221 MPa;

[0031] Figure 5 It is a strain distribution diagram of the aluminum alloy shell in Comparative Example 2 at the chamber pressure of 221 MPa;

[0032] Figure 6 It is a stress distribution diagram of the shell cylinder in Example 1 at the chamber pressure of 221 MPa;

[0033] Figure 7 It is a strain distribution diagram of the shell cylinder in Example 1 at the chamber pressure of 221 MPa;

[0034] Figure 8A physical diagram of a composite continuous pressure cylinder in the present application;

[0035] Figure 9 A physical diagram of a composite shell cylinder in the present application;

[0036] Figure 10 A physical diagram of a shell obtained by a PA66 shell cylinder + carbon fiber continuous pressure cylinder;

[0037] Figure 11 A physical diagram of a shell obtained by a PA66 + 40% long basalt fiber shell cylinder + carbon fiber continuous pressure cylinder;

[0038] Figure 12 A physical diagram of a shell obtained by a PA66 + 40% long glass fiber shell cylinder + carbon fiber continuous pressure cylinder;

[0039] Figure 13 A physical diagram of a shell obtained by a PA66 shell cylinder + basalt fiber continuous pressure cylinder;

[0040] Figure 14 A physical diagram of a shell obtained by a PA66 + 40% long basalt fiber shell cylinder + basalt fiber continuous pressure cylinder. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below. If specific conditions are not indicated in the embodiments, the conventional conditions or the conditions suggested by the manufacturers are adopted. If the reagents or instruments used are not indicated by the manufacturers, they are all conventional products that can be purchased in the market.

[0042] The present embodiment provides a composite shell, the material of the shell is a composite material, the composite material includes a thermosetting or thermoplastic matrix material and a fiber material, the fiber material includes at least one of basalt fiber, polyimide fiber and aramid fiber.

[0043] The high-performance composite shell of the present application adopts lightweight high-strength basalt fiber composite material, polyimide composite material and aramid fiber composite material to replace the original shell in order to eliminate the phenomena such as shell burst and shell rupture of the plastic shell when the bullet is fired, so as to reduce the overall weight of the product while meeting the performance of the shell, so as to achieve the purpose of lightening.

[0044] In some embodiments of the present application, the shell includes a shell cylinder and an ignition hole on the shell cylinder, a continuous pressure cylinder is arranged at one end of the shell cylinder close to the ignition hole, and the continuous pressure cylinder is a composite material.

[0045] In order to eliminate the phenomenon of the existing plastic shell being blown off and the shell being broken when a bullet is fired, a light-weight high-strength basalt fiber composite continuous pressure cylinder is used to replace the original metal base to bear most of the bore pressure generated during use of the product.

[0046] In some embodiments of the present application, the continuous pressure cylinder is obtained by die molding or wet molding.

[0047] The basalt fiber composite continuous pressure cylinder can resist blasting impact, and the die molding or wet molding method is more conducive to improving the blasting impact resistance of the continuous pressure cylinder. The die molding process can make the continuous pressure cylinder be formed at one time, and the size is accurate and the surface is smooth, the appearance and size of the continuous pressure cylinder are good in repeatability, and mass production can be realized by mechanization and automation. In addition, since the structure of the composite continuous pressure cylinder is simple and there is no high requirement on the appearance, the use of die molding or wet molding is more convenient.

[0048] In some embodiments of the present application, the matrix material of the continuous pressure cylinder is a liquid resin, and the mass fraction of the matrix material in the continuous pressure cylinder is 60-70%, for example, the matrix material can be epoxy resin, phenolic resin, polyethylene and polyformaldehyde, etc.

[0049] In some embodiments of the present application, the fiber material in the continuous pressure cylinder is basalt fiber plain cloth or basalt fiber twill cloth, and the area density is 200-500 g / m 2 , for example, it can be 200 g / m 2 , 300 g / m 2 , 400 g / m 2 , 500 g / m 2 , etc.

[0050] In some embodiments of the present application, the continuous pressure cylinder is obtained by coating liquid resin on the surface of basalt fiber and then die molding or wet molding.

[0051] In some embodiments of the present application, the shell cylinder is obtained by injection molding; or the continuous pressure cylinder is used as an insert, and the insert injection molding method is used to obtain the shell.

[0052] The composite forming shell cylinder is selected to meet the performance of the shell while reducing the overall weight of the product to achieve the purpose of lightening. Since the continuous pressure cylinder belongs to thermosetting composite material, the shell cylinder belongs to thermoplastic material, and the shell belongs to precision product, the connection between them cannot be achieved by welding or punching. Therefore, the research project adopts the insert injection molding forming process. Insert molding refers to the injection of resin after the pre-prepared insert of different materials is installed in the mold. The molten resin combines with the insert to solidify and form an integrated product. The insert molding process makes the continuous pressure cylinder and the shell cylinder tightly connected without void defects. On the other hand, it also ensures the coaxiality of the two products to ensure that the continuous pressure cylinder can maximize its ability to withstand most of the bore pressure generated when the bullet is fired.

[0053] In addition, the continuous pressure cylinder and the shell cylinder can be formed by insert injection molding, which improves the consistency of the product to ensure its precision during mass production, and realizes automatic, standardized and large-scale mass production.

[0054] In some embodiments of the present application, the forming material in the shell cylinder is a solid plastic or a solid composite material, such as polypropylene, nylon, polyformaldehyde, polyphenylene sulfide, etc.

[0055] In some embodiments of the present application, the volume fraction of basalt fibers in the shell cylinder is 30-50%, such as 30%, 35%, 40%, 45% or 50%.

[0056] In some embodiments of the present application, the shell cylinder is sequentially provided with a first shell cylinder segment, a second shell cylinder segment and a third shell cylinder segment in the direction away from the detonation hole, the wall thickness of the first shell cylinder segment, the second shell cylinder segment and the third shell cylinder segment gradually decreases, and the continuous pressure cylinder is located in the first shell cylinder segment.

[0057] According to the stress condition of the shell cylinder, the wall thickness of the shell cylinder is adjusted to avoid the phenomenon of burst and fracture when the bullet is fired.

[0058] Another embodiment of the present application provides a processing method of the basalt fiber composite shell as described in any one of the preceding embodiments, which comprises continuous pressure cylinder forming and shell cylinder forming.

[0059] The continuous pressure cylinder is formed by molding or wet forming, the shell cylinder is formed by injection molding, and then the continuous pressure cylinder and the shell cylinder are assembled; or, the continuous pressure cylinder is formed by molding or wet forming, and then the continuous pressure cylinder is used as an insert to obtain the shell by insert injection molding.

[0060] In an optional embodiment, it comprises:

[0061] The liquid resin is coated on the surface of the basalt fiber, and is pre-cured at 35-45℃ for 1-2h, and then is molded by molding or wet forming to obtain a continuous pressure cylinder;

[0062] The continuous pressure cylinder is used as an insert, and is integrally injection molded at 270-290℃ by an insert injection molding process to obtain a basalt fiber composite shell.

[0063] Another embodiment of the present application provides a bullet comprising the shell of any one of the above.

[0064] The features and performances of the present application are further described in detail below in combination with embodiments.

[0065] Embodiment 1

[0066] The present embodiment provides a basalt fiber composite shell, which comprises a shell cylinder and an ignition hole on the shell cylinder, and a continuous pressure cylinder is arranged at one end of the shell cylinder close to the ignition hole.

[0067] The continuous pressure cylinder structure is shown in Figure 1 , which can be used to replace the metal base of the traditional bullet, so that the bullet can not be exploded or broken when shooting, and the overall weight of the bullet is reduced. The outer diameter D of the continuous pressure cylinder is Φ18.8mm, the inner diameter d of the continuous pressure cylinder is Φ17.5mm, and the overall height h of the continuous pressure cylinder is 18.9mm. The processing method of the basalt fiber composite continuous pressure cylinder in the present embodiment is as follows: since the structure of the composite continuous pressure cylinder is simple and the appearance has no high requirements, the molding method is used for preparation. Specifically, a plain weave basalt fiber cloth with a surface density of 300g / m 2 is selected, and the prepared epoxy resin is uniformly coated on the surface of the basalt fiber cloth so that the basalt fiber cloth is fully infiltrated. The basalt fiber cloth is laid in a circumferential and axial manner, and the number of layers of the inner continuous pressure cylinder is 3. The basalt fiber cloth coated with the epoxy resin is pre-cured at 40℃ for 1.5h, and then the basalt fiber composite continuous pressure cylinder is obtained by molding.

[0068] The shell cylinder structure is shown in Figure 2As shown in the figure, the total length L of the shell is 65 mm, the bottom edge diameter D is Φ22.45 mm, the bottom edge root diameter D1 is Φ20.55 mm, the shell mouth outer diameter D2 is Φ20.15 mm, the bottom edge inner diameter d is Φ17.5 mm, the shell cylinder inner diameter d1 is Φ18.47 mm; the bottom edge thickness h is 1.81 mm. The shell accounts for almost half of the total bullet weight, and plays a role in safety protection, support, connection containment, protection of the cartridge chamber and the like, and PA66+40% basalt fiber long cut material is selected as the shell cylinder forming material. The processing method of the basalt fiber composite continuous pressure cylinder in the embodiment is: using insert injection molding process and basalt fiber composite continuous pressure cylinder to integrally injection mold at 280°C to obtain basalt fiber composite shell product. Compared with the forming material of the traditional shell, the shell cylinder is formed by using the characteristics of high modulus, high strength, instant high temperature resistance and non-toxicity of basalt fiber in the embodiment, which meets the performance requirements of the bullet; in terms of forming process, the continuous pressure cylinder and the shell cylinder are integrated by using the insert molding process, which can reduce the difference between the products, improve the production efficiency, and the real object diagram of the continuous pressure cylinder and the shell cylinder is as shown in the figure Figure 8 and Figure 9 as shown.

[0069] Comparative Example 1

[0070] In this comparative example, long glass fiber is selected as the reinforcing material, and the mass fraction of the glass fiber is 50%, and the matrix material is nylon 66. The composite shell is injection molded at 260°C-280°C, and the specific structure of the shell cylinder is the same as that in Example 1. The bullet explodes during shooting, and the results are as shown in the figure Figure 3 , the bottom of the shell cracks, and after the gun is disassembled and the shell is damaged, the stress is concentrated at the intersection position of the bottom edge and the side edge due to the fact that the shell hook quickly hooks the flange edge of the bottom of the shell, which is torn from this position first, and the high pressure inside quickly tears the side edge of the bullet shell along the bottom crack.

[0071] Comparative Example 2

[0072] The specific structure of the shell in this comparative example is the same as that of the shell cylinder in Example 1, and the material is aluminum alloy material.

[0073] Experimental Example: CAE Analysis

[0074] (1) Material Performance Parameter Table

[0075] Table 1 Material parameters of aluminum alloy in Comparative Example 2 and PA66+40% long basalt fiber material in Example 1

[0076]

[0077]

[0078] Table 2 300g / m 2 Basalt fiber plain cloth material parameters

[0079] Item Unit 300 g / m 2 Basalt fiber plain cloth Tensile strength MPa 479 Mass per unit area g / m 2 ]] 300 Moisture content ％ 0.01 Combustible content ％ 0.60

[0080] (2) Loading conditions

[0081] The chamber pressure is gradually increased from 0 until the stress or strain of the aluminum alloy shell exceeds the allowable value, and then the stress and strain of the aluminum alloy shell under the maximum pressure it can withstand and the continuous pressure cylinder in Example 1 are analyzed. After analysis, it is found that when the loaded chamber pressure reaches 221 MPa, the maximum allowable stress of the aluminum alloy material is reached. The comparison of the stress and strain analysis results of the aluminum alloy shell in Comparative Example 2 and the continuous pressure cylinder in Example 1 is shown in Table 3 and Figures 4-7 .

[0082] Table 3 Comparison of stress and strain analysis results

[0083]

[0084] According to the simulation analysis data, when the chamber pressure of the composite shell in Example 1 reaches the same as that of the aluminum alloy shell in Comparative Example 2, the innermost layer of the continuous pressure cylinder with 3 layers is only damaged, and the entire shell does not explode. That is, the continuous pressure cylinder withstands most of the chamber pressure generated by the bullet shooting, which also proves the feasibility of the scheme of adding a continuous pressure cylinder in the first shell cylinder segment.

[0085] The application also compares the materials of the continuous pressure cylinders and the shell cylinders. The difference between the shell and Example 1 is only in the material. The shells with different material continuous pressure cylinders and shell cylinders are observed, and the results are shown in Table 4 and Figures 10-14 .

[0086] Table 4 Comparison of different material shells

[0087]

[0088] As can be seen from Figures 10-14 , compared with the basalt fiber composite continuous pressure cylinder, the shell prepared by the carbon fiber composite continuous pressure cylinder not only has defects, but also may crack or break, and whether PA66 or long glass fiber is used as the shell cylinder or the continuous pressure cylinder, or without the continuous pressure cylinder, the obtained shell will be damaged in the beating experiment, and the performance is far inferior to that of the basalt fiber composite material.

[0089] Table 5 Comparison of properties of different fibers

[0090]

[0091]

[0092] The above Table 5 is a comparison of various properties among basalt fibers, polyimide fibers and aramid fibers, and it can be seen that the properties of the three kinds of fibers are not much different, and all can ensure the performance of the composite shell while reducing the weight and the production cost.

[0093] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A bullet having a high performance composite jacket, characterized in that, The material of the shell is a composite material, the shell comprises a shell cylinder and an ignition hole on the shell cylinder, and a continuous pressure cylinder is arranged at one end of the shell cylinder close to the ignition hole; The shell cylinder is a thermoplastic composite material, the thermoplastic composite material comprises a thermoplastic base material and a fiber material in the shell cylinder, and the fiber material in the shell cylinder comprises at least one of basalt fiber, polyimide fiber and aramid fiber; The continuous pressure cylinder is a thermosetting composite material, the thermosetting composite material comprises a thermosetting base material and a fiber material in the continuous pressure cylinder, and the thermosetting base material is a liquid resin; The mass fraction of the thermosetting base material of the continuous pressure cylinder is 60-70%; The continuous pressure cylinder is obtained by applying liquid resin on the surface of basalt fiber plain cloth or basalt fiber twill cloth and then performing mold forming or wet forming, and the areal density of the basalt fiber plain cloth or basalt fiber twill cloth is 200-500 g / m 2 .

2. The bullet having a high performance composite jacket according to claim 1, wherein, The shell cylinder is formed by a solid composite material.

3. The bullet having a high performance composite jacket according to claim 2, wherein, The volume fraction of the fiber material in the shell cylinder is 30-50%.

4. The bullet having a high performance composite jacket according to claim 1, wherein, The shell cylinder is sequentially provided with a first shell cylinder segment, a second shell cylinder segment and a third shell cylinder segment in the direction away from the ignition hole, the wall thicknesses of the first shell cylinder segment, the second shell cylinder segment and the third shell cylinder segment gradually decrease, and the continuous pressure cylinder is located in the first shell cylinder segment.

5. A method of processing a bullet having a high performance composite material shell according to any one of claims 1 to 4, characterized in that, The continuous pressure cylinder is formed and the shell is formed; The continuous pressure cylinder is formed by die molding or wet molding, the shell cylinder is formed by injection molding, and then the continuous pressure cylinder and the shell cylinder are assembled; or The continuous pressure cylinder is formed by die molding or wet molding, and then the continuous pressure cylinder is used as an insert to form the shell by insert injection molding.

6. The method of working a bullet having a high performance composite jacket according to claim 5, wherein, It comprises: The liquid resin is coated on the surface of the basalt fiber, and is pre-solidified at 35-45℃ for 1-2h, and then is formed by die molding or wet molding to obtain the continuous pressure cylinder; When the continuous pressure cylinder is used as an insert, the insert injection molding process is adopted to integrally injection mold at 270-290℃ to obtain the shell.

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