Melt cast explosive using aluminum wool, and preparation method therefor

Abstract

The present invention relates to: a melt cast explosive using an aluminum wool, the explosive containing a molecular explosive that can be mixed in the aluminum wool and melted; and a preparation method therefor, and thus the brittleness of a conventional melt cast explosive using an aluminum powder can be alleviated and preparation is possible through a preparation process that is simpler than a conventional preparation method using an aluminum powder.

Description

Melt-cast gunpowder using aluminum fiber and its manufacturing method

[0001] The present invention relates to a molten cast gunpowder using aluminum mother fibers and a manufacturing method thereof, and more particularly, to a molten cast gunpowder using aluminum mother fibers and a manufacturing method thereof, which uses aluminum in the form of wool rather than aluminum in the form of powder.

[0002] Metallic materials are widely used as fuels to increase the energy density of high-energy material complexes such as propellants, high explosives, and pyrotechnics due to their high oxidation heat and high density.

[0003] In particular, aluminum has a high per-weight or per-volume (7.42 kcal / g, 20.03 kcal / cm 3 ) It is the most widely used metal fuel material because it has combustion heat, and when applied to high explosives, it can be used as thermobaric explosives.

[0004] The above thermobaric explosive powder has an increased pressure duration and consequently an increase in impulse, resulting in excellent blast performance, as compared to when only pure molecular explosives are used, due to the reaction between the explosive product gas after the explosion of the gunpowder, particularly the oxygen in the air and aluminum, and more specifically, the afterburning reaction. For example, Tritonal (TNT: Al = 80:20 wt%) is known to have a blast performance that is approximately 18% higher than that of TNT (Trinitrotoluene) alone, and is used as the main charge of the Mark 82 (Mk82) bullet among the Mark 80 bullet series of the United States.

[0005] Aluminum used in the manufacture of the above thermo-pressure explosives is mainly applied in the form of powder that has a large surface area, excellent reactivity, and is easy to disperse in a medium, and is used as a filler in melt cast molecular explosives such as TNT (Trinitrotoluene) and DNP (Dinitropyrazole).

[0006] In the above molten cast-type explosive manufacturing process, the molecular explosive TNT (81°C) or DNP (85°C) is heated to a temperature higher than the melting point to make it into a liquid state, and then a metal fuel material, for example, aluminum, is dispersed therein, and this is filled into a casting mold or projectile of a desired shape, and then cooled and solidified for use.

[0007] As shown in Fig. 1, the manufacturing process of Tritonal, an aluminum-based molten cast gunpowder, involves the steps of manufacturing molten TNT, adding and stirring aluminum powder -> manufacturing Tritonal suspension -> heating the casting mold -> discharging the suspension and casting it into the mold -> continued stirring, cooling, and solidification -> completing Tritonal manufacturing, so there is a difference in density between the upper and lower parts.

[0008] At this time, A of Fig. 1 shows the state of aluminum sedimentation and blockage of the container outlet due to the density difference, and B of Fig. 1 shows the state of aluminum sedimentation occurring after casting molten gunpowder in a mold until the molten gunpowder solidifies.

[0009] However, since organic-based molecular explosives typically have lower densities than metals, if strong stirring is not applied during the manufacturing process, as shown in Table 1 below, the metal powder may settle to the bottom of the container due to the density difference, blocking the container's outlet.

[0010] Material density (g / cm) 3 )TNT(Trinitrotoluene)1.64DNP(Dinitropyrazole)1.85Al(Aluminum)2.7

[0011] Additionally, if the TNT or DNP is not stirred until it solidifies after casting into the mold, the aluminum settles and becomes unevenly distributed, making it difficult to exhibit consistent blast performance and mechanical properties. To overcome this unevenness, a solid solution filling method, as shown in Figure 2, is used in the manufacture of Tritonal.

[0012] That is, it is manufactured through the steps of melting TNT and adding aluminum powder -> manufacturing a tritonal suspension for flakes -> solidifying the suspension to manufacture flakes for solid solution filling -> manufacturing a tritonal suspension for casting -> heating the casting mold -> discharging the suspension and filling it into the mold and periodically adding flakes -> continued stirring, continued stirring, cooling, and solidification -> completing the manufacture of tritonal.

[0013] At this time, C of Fig. 2 shows a state of discharging a tritonal suspension, D of Fig. 2 shows a state of solidifying the suspension to form tritonal flakes, E of Fig. 2 shows a state of discharging the suspension into a preheated mold, and F shows a state of periodically adding tritonal flakes while stirring.

[0014] A solid solution is a slurry state in which molten gunpowder and partially crystallized (solidified) gunpowder are mixed together. The solid solution charging method is a charging method in which a tritonal suspension is first manufactured and solidified to make it into a flake state, and then when casting another tritonal suspension into a mold, the previously manufactured flakes are also added and stirred to make it into a slurry state to induce simultaneous crystal growth and solidification.

[0015] In addition, since the slurry state of flakes and molten gunpowder has a higher viscosity than the pure liquid state, if it is accompanied by appropriate stirring until solidification, the problem of aluminum powder settling due to density difference can be improved.

[0016] However, this method not only requires an additional process for manufacturing flakes, but also requires continued stirring after casting in the mold, as in the conventional manufacturing process (Fig. 1).

[0017] In addition to these manufacturing process shortcomings, molten cast gunpowder, including TNT, is inherently hard but brittle, requiring care when handling. In addition, when used as a main charge in weapon systems, it is vulnerable to external stimuli such as internal shock and penetrating shock.

[0018] The purpose of the present invention is to provide a molten cast gunpowder using aluminum fibers and a manufacturing method thereof, which can improve the shortcomings and manufacturing method problems of existing molten cast gunpowders using aluminum powder (Tritonal is presented as a representative example in the present invention).

[0019] A molten-cast gunpowder using aluminum matrix fibers according to an embodiment of the present invention for solving the above technical problem is characterized by including: aluminum matrix fibers; and a molecular gunpowder that can be melted by mixing it with the aluminum matrix fibers.

[0020] The above aluminum mother fiber is characterized by having a diameter of 10 to 100 μm.

[0021] The above molecular explosive is characterized by being composed of TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

[0022] Meanwhile, a method for manufacturing a molten cast gunpowder using aluminum matrix fibers according to an embodiment of the present invention is characterized by including the steps of: filling aluminum matrix fibers into a filling mold; heating the aluminum matrix fibers in the filling mold; melting and liquefying molecular gunpowder; casting the liquid of the molecular gunpowder into the heated filling mold so as to be mixed; and cooling and solidifying the filling mold.

[0023] The above aluminum fiber is characterized in that it is filled into the filling mold so as to be uniformly compressed to a constant volume and weight.

[0024] The above molecular explosive is characterized by being TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

[0025] It is characterized in that the aluminum mother fiber in the above charging mold is preheated to a certain melting point or higher of the molecular gunpowder.

[0026] The melting point is characterized by being 81°C or higher in the case of TNT (Trinitrotoluene) and 85°C or higher in the case of DNP (Dinitropyrazole).

[0027] The above aluminum fiber and the above TNT (Trinitrotoluene) are characterized by being 20:80 wt%.

[0028] The present invention is a molten cast gunpowder and a manufacturing method using aluminum matrix fibers including a meltable molecular gunpowder mixed into aluminum matrix fibers, so that the brittleness of molten cast gunpowder using existing aluminum powder can be improved, and compared to a manufacturing method using existing aluminum powder, it has the effect of being manufactured through a simple manufacturing process.

[0029] Figure 1 is a manufacturing process diagram of Tritonal using existing aluminum powder.

[0030] Figure 2 is a manufacturing process diagram of Tritonal using a conventional solid solution filling method.

[0031] Figure 3 is an example of aluminum wool according to the present invention.

[0032] Figure 4 is a manufacturing process diagram of tritonal using aluminum mother fiber according to the present invention.

[0033] Figure 5 is a graph showing the average compressive strength (MPa) and average compressive strain (%) of the solid solution filling method and aluminum mother fiber according to the present invention.

[0034] Figures 6(a)(b) are comparative examples showing the molten cast gunpowder of the existing aluminum powder-applied tritonal and the aluminum fiber-applied tritonal of the present invention, respectively.

[0035] Hereinafter, to fully understand the present invention, preferred embodiments of the present invention will be described with reference to the attached drawings, FIGS. 3 to 6. The embodiments of the present invention may be modified in various ways, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. It should be noted that in each drawing, identical components are sometimes depicted with the same reference numerals. Detailed descriptions of well-known functions and components that may unnecessarily obscure the gist of the present invention are omitted.

[0036] Referring to FIGS. 3 and 4, the molten cast gunpowder (400) of the present invention is composed of aluminum matrix fibers (100) and a meltable molecular gunpowder (200) mixed with the aluminum matrix fibers (100) to increase compressive strength and strain.

[0037] At this time, the aluminum mother fiber (100) is a filler of the molecular gunpowder (200), has a diameter of 10 to 100 μm, and after compression of the aluminum mother fiber, the apparent density is at the level of 0.31 to 0.33 g / cm3. Each picture in Fig. 3 is an example according to the apparent density and the photograph angle.

[0038] It is preferable that the above molecular explosive (200) is composed of TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

[0039] Referring to FIGS. 4 and 6, a method for manufacturing a molten cast gunpowder using aluminum matrix fibers according to an embodiment of the present invention comprises the steps of: charging aluminum matrix fibers (100) into a charging mold (300); heating the aluminum matrix fibers (100) through the charging mold (300) to maintain the temperature above the melting point of molecular gunpowder (200); melting and liquefying the molecular gunpowder (200); casting the liquid of the molecular gunpowder (200) so as to be mixed into the heated charging mold (300); and cooling and solidifying the charging mold (300).

[0040] At this time, it is preferable that the aluminum mother fiber (100) is uniformly compressed into the filling mold (300) to a certain volume and weight.

[0041] It is preferable that the above molecular explosive (200) is made of TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

[0042] It is preferable to preheat the aluminum mother fiber (100) in the above charging mold (300) to a certain melting point or higher of the molecular gunpowder (200).

[0043] That is, the reason for preheating is that it is necessary to prevent all parts that come into contact with the molecular explosive (200) made of TNT or DNP from cooling below the melting point of the molecular explosive (200) until the charging process is completed.

[0044] If either the mold or the parent fiber is cooled below the melting point of the molecular powder (200), the molecular powder (200) solidifies and cannot penetrate the aluminum parent fiber (100).

[0045] For example, when the upper part of the aluminum mother fiber (100) is cooled, a plate of molecular gunpowder (200) is formed on the upper part of the aluminum mother fiber (100), preventing gunpowder from being charged inside.

[0046] The melting point is preferably 81°C or higher in the case of TNT (Trinitrotoluene) and 85°C or higher in the case of DNP (Dinitropyrazole).

[0047] It is preferable that the above aluminum mother fiber (100) and the above TNT (Trinitrotoluene) be in a weight ratio of 20:80.

[0048] That is, the above aluminum mother fiber (100) can improve the brittleness of a molten cast gunpowder using existing aluminum powder by functioning as an aluminum component and at the same time as a structural reinforcing material, and can be manufactured through a simple manufacturing process compared to a manufacturing method using existing aluminum powder.

[0049] The meltable molecular explosive (200) using the aluminum matrix fiber (100) of the present invention showed improved brittleness as shown in Table 2 below, as shown in the compression test results (performed 3 times per sample) of Tritonal (TNT / aluminum = 80 / 20 wt%), and the application of the aluminum matrix fiber (100) resulted in a higher average compressive strength (MPa) and average compressive strain (%) than when using the existing aluminum powder. The compression test was performed on cylindrical pellets with a diameter of 18 mm and a height of 18 mm using an Instron universal testing machine, and the compression speed at that time was 0.5 mm per minute (the pellets were compressed at 0.5 mm / min).

[0050] Material sample (Tritonal-solid solution filling method) Average compressive strength (MPa) Average compressive strain (%) Maximum 3 times Average Maximum 3 times Existing aluminum powder #116.2016.2015.921.151.151.09 #215.671.05 #315.891.07 Aluminum fiber of the present invention #429.6037.634.923.565.985.00 #537.585.98 #637.65.47

[0051] In this way, the meltable molecular gunpowder (200) using the aluminum mother fiber (100) of the present invention can produce a tritonal product having a density almost similar to that of the solid solution filling method without requiring an additional flake manufacturing process required in the solid solution filling method, as shown in Table 3 and FIG. 5 below.

[0052] Material sample (Tritonal-solid solution filling method) Relative density Non-conventional aluminum powder 100 Aluminum mother fiber of the present invention 96.04

[0053] Fig. 6(a)(b) are comparative examples showing the molten cast type explosives of the existing aluminum powder-applied tritonal and the aluminum base fiber-applied tritonal of the present invention, respectively. The tritonal of the meltable molecular explosive (200) using the aluminum base fiber (100) of the present invention has a slightly reduced blast performance compared to the existing aluminum powder-applied tritonal in the enlarged portions of Fig. 6(a)(b), despite the difference in density, as shown in Table 4 through the in-tunnel blast performance test, and has almost similar performance. This can be confirmed to be at the same level within the margin of error.

[0054]

[0055] Material sample (Tritonal-solid solution filling method) Storm performance ratio (same mass) Maximum pressure impulse Existing aluminum powder 100 100 Aluminum mother fiber of the present invention 98.1 95.8

[0056] Meanwhile, the present invention is not limited to the above-described embodiments, but can be implemented by modifying and changing the same within the scope that does not deviate from the gist of the present invention, and the technical ideas to which such modifications and changes are applied should also be considered to fall within the scope of the following patent claims.

Claims

1. Aluminum mother fiber (100); and A molten cast gunpowder using aluminum matrix fibers, characterized in that it includes a meltable molecular gunpowder (200) mixed into the aluminum matrix fibers (100).

2. In claim 1, A molten cast gunpowder using aluminum mother fibers, characterized in that the above aluminum mother fibers (100) have a diameter of 10 to 100 μm.

3. In claim 1, The above molecular gunpowder (200) is a molten cast gunpowder using aluminum fibers, characterized in that it is made of TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

4. Step of filling aluminum fiber (100) into a filling mold (300); A step of heating the aluminum mother fiber (100) within the above charging mold (300); A step of melting and liquefying molecular gunpowder (200); A step of casting the liquid of the above molecular gunpowder (200) so as to be mixed in the heated charging mold (300); and A method for manufacturing a molten cast gunpowder using aluminum fiber, characterized in that it includes a step of cooling and solidifying the above-mentioned filling mold (300).

5. In claim 4, A method for manufacturing a molten cast gunpowder using aluminum fibers, characterized in that the aluminum fibers (100) are uniformly compressed into the filling mold (300) to a constant volume and weight.

6. In claim 4, A method for manufacturing a molten cast gunpowder using aluminum fibers, characterized in that the above molecular gunpowder (200) is TNT (Trinitrotoluene) or DNP (Dinitropyrazole).

7. In claim 6, A method for manufacturing a molten cast gunpowder using aluminum fibers, characterized in that the aluminum fibers (100) in the charging mold (300) are preheated to a certain melting point or higher of the molecular gunpowder (200).

8. In claim 7, A method for manufacturing a molten cast gunpowder using aluminum fiber, characterized in that the melting point is 81°C or higher in the case of TNT (Trinitrotoluene) and 85°C or higher in the case of DNP (Dinitropyrazole).

9. In claim 8, A method for manufacturing a molten cast gunpowder using aluminum fiber, characterized in that the aluminum fiber (100) and the TNT (Trinitrotoluene) are 20:80 wt%.

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