Flexible multifunctional energetic fiber and its rapid manufacturing method

Abstract

The application discloses a flexible multifunctional energetic fiber and a rapid manufacturing method thereof, the energetic fiber is laid on a target surface of a complex curved surface by 3D printing, the energetic fiber comprises a plurality of energetic units, the energetic units are connected by energetic sheets and energetic filaments, the energetic sheet is a combination of a titanium mesh and a desensitizing oxide, and the energetic filament is a titanium filament. The manufacturing method comprises the following steps: manufacturing the energetic sheet; combining the energetic sheets and the energetic filaments into the energetic fiber; and laying the energetic fiber on the target surface of the complex curved surface. The application can realize the continuous 3D printing manufacturing of the energetic fiber integrated by the energetic units on the surface of any complex curved surface, and thus rapid large-area synchronous ignition can be realized on any target needing to be burned or providing a heat source.

Description

Technical Field

[0001] The present invention belongs to the field of advanced manufacturing technology, and in particular relates to a flexible multifunctional energetic fiber and a rapid manufacturing method thereof. Background Art

[0002] Energetic agents are widely used in aerospace, national defense and military industries. The diverse categories of energetic agents involve different application scenarios. For scenarios such as structural and electronic device damage that require rapid heat provision, the material formula is generally black powder, thermite and other low-insensitivity explosives. The complex structure of the design ensures reliability in use, but it still cannot completely guarantee that there will be no loss of control problems. Moreover, due to the complexity of the existing energetic damage structure, large-scale synchronous fire cannot be achieved, and the scenario applicability is poor.

[0003] In recent years, researchers have developed novel structural and formulation designs for igniters (An Yong Yamin et al., Chinese invention patent CN202011541367.6; Wei Hao et al., Chinese invention patent CN202111222258.2; Chen Likui et al., Chinese invention patent CN201110443121.X), creating a variety of ignition structures and novel ignition formulations for different applications. However, current issues such as complex structures and poor applicability remain unresolved. Summary of the Invention

[0004] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a flexible multifunctional energetic fiber and a rapid manufacturing method thereof, which can complete the continuous 3D printing and manufacturing of energetic fibers integrated by energetic units on the surface of any complex curved surface, for any target that needs to be burned or provide a heat source, thereby achieving rapid and large-area synchronous ignition.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] The present invention provides an energetic fiber that can achieve synchronous burning of large-area arbitrarily complex curved surfaces. The energetic fiber includes an energetic fiber, which is laid on a target surface of a complex curved surface using 3D printing; the energetic fiber includes a plurality of energetic units, which are connected by an energetic sheet and an energetic wire. The energetic sheet is a combination of a titanium mesh and an insensitive oxide, and the energetic wire is a titanium wire.

[0007] Furthermore, the insensitive oxide is hydroxylamine nitrate.

[0008] The present invention also provides a method for rapidly manufacturing flexible multifunctional energetic fibers, comprising the following steps:

[0009] (1) Manufacturing energetic tablets;

[0010] (2) combining a plurality of energetic sheets and energetic filaments into energetic fibers;

[0011] (3) Laying the energetic fiber onto the target surface with complex curves.

[0012] Furthermore, the step (1) includes the following sub-steps:

[0013] (11) mixing the insensitive oxide and the polymer material to form a slurry;

[0014] (12) The titanium mesh and the slurry are pressed into thin sheets by hot pressing or hot roller pressing to obtain an energetic sheet.

[0015] Furthermore, the insensitive oxide is hydroxylamine nitrate, and the polymer material is polyvinyl alcohol.

[0016] Furthermore, the step (2) includes the following sub-steps:

[0017] (21) cutting the energetic sheet into a desired shape;

[0018] (22) Titanium wires were sewn onto energetic sheets through fixed lines to continuously produce energetic fibers with energetic sheets and energetic wires arranged at intervals.

[0019] Furthermore, an energetic fiber is prepared using an energetic fiber manufacturing device, the energetic fiber manufacturing device comprising a front roller, a sewing needle, a cutting knife, a rear roller, a positioning block, and a support plate; the front roller and the rear roller are arranged in parallel, respectively comprising an upper roller and a lower roller, for feeding and positioning the metal strip; the sewing needle, the cutting knife, and the positioning block are located between the front roller and the rear roller and above the support plate, the positioning block is used to position the metal strip, and through holes cooperating with the cutting knife and the sewing needle are respectively provided on the support plate, the cutting knife is used to cut the metal strip one by one to a set length of the energetic sheet, and the sewing needle is used to fix the titanium wire to the energetic sheet;

[0020] The preparation process comprises the following steps:

[0021] 1) Feeding of metal strip: The metal strip enters from the rear roller, passes through the positioning block, cutting knife, sewing needle in sequence, and is bitten by the front roller;

[0022] 2) Titanium wire fixing: The sewing needle passes through the metal belt, hooks the titanium wire below with a fixing line, fixes the titanium wire on the metal belt, and cooperates with the continuous rotation of the front and rear rollers to keep the sewing needle moving;

[0023] 3) Metal strip cutting: When the metal strip reaches the set length of the energy unit, the cutting knife cuts the metal strip. After cutting, the front roller rolls for a set time to send the connected part out a set distance, which is the set length of the titanium wire.

[0024] 4) Continuous feeding: The front and rear rollers then work simultaneously again, and the sewing needle also starts working until the next energetic sheet reaches a set length. This cycle is repeated to prepare an energetic fiber structure with alternating energetic sheets and titanium wires.

[0025] Furthermore, the step (3) includes the following sub-steps:

[0026] (31) transporting the energetic fiber to a printing position via a roller;

[0027] (32) The energetic fiber is made sticky by a heating module so as to adhere to the target surface;

[0028] (33) Through the continuous conveying of rollers and the cooperation of robotic arms, energetic fibers can be laid over a large area on a target with a complex curved surface.

[0029] The beneficial effects of the present invention compared to the prior art are as follows:

[0030] (1) A new type of insensitive energetic agent formula is proposed. By utilizing the characteristics of titanium material, which is stable at room temperature and active at high temperature, a fast energetic unit with good insensitivity and low input energy is manufactured. This solves the industry pain point of high sensitivity of explosives in the field of energetic materials. The manufacturing method is simple and the ignition is reliable.

[0031] (2) A new design concept and manufacturing method for energetic fibers are proposed. The energetic units are combined together by sewing to form a whole energetic fiber. While retaining the characteristics of the energetic units themselves, the ignition from point to line is achieved.

[0032] (3) To improve the scenario applicability of energetic agents, the energetic fibers are laid on the target surface through a tape laying process, which is a first in the field of energetic agents. From line to surface, a ignition surface is formed that can ignite synchronously. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Schematic diagram for the design, manufacturing and printing of energetic fibers.

[0034] Figure 2 Schematic diagram of the energetic fiber structure.

[0035] Figure 3 Schematic diagram of the energetic unit structure.

[0036] Figure 4 This is a physical picture of the energetic unit.

[0037] Figure 5 Schematic diagram of the process for manufacturing energetic fibers.

[0038] Figure 6 3D schematic diagram of the process for manufacturing energetic fibers.

[0039] Figure 7Schematic diagram of the energetic fiber placement process.

[0040] Figure 8 3D schematic diagram of the energetic fiber placement process.

[0041] Figure 9 Schematic diagram of the actual placement of energetic fibers. DETAILED DESCRIPTION

[0042] In order to make the purpose and technical solution of the invention more clear, the following are explained with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the invention and are not used to limit the invention.

[0043] The present invention provides an energetic fiber that can realize synchronous ignition of large-area, arbitrarily complex curved surfaces, such as Figure 1 As shown, for a target with a complex curved surface, a 3D printing method is used to lay energetic fibers on the target surface to achieve rapid and synchronous ignition. This energetic fiber utilizes an energetic fiber of arbitrary length and is evenly laid on the target surface through 3D printing by a robotic arm. Only a low voltage needs to be input at both ends to cause the entire surface to ignite, thereby burning the target.

[0044] Energetic fibers are composed of multiple energetic units, such as Figure 2 As shown, the energetic unit is shown in the dotted box and is composed of energetic filaments and energetic sheets. The energetic units are connected together by metal wires and polymer wires to form a whole fiber, which serves as the raw material for energetic fiber printing.

[0045] The energetic unit is composed of energetic sheets and energetic wires connected together, such as Figure 3 As shown in the figure, the energetic wire is titanium wire, and the energetic sheet is a combination of titanium mesh and insensitive oxide (such as hydroxylamine nitrate, HAN, etc.). The titanium wire has a special effect when it is electrified, and the combustion of the energetic sheet is triggered by the explosion of the titanium wire.

[0046] The present invention also provides a method for manufacturing energetic fibers that can achieve synchronous ignition of large-area, arbitrarily complex curved surfaces, which includes three parts: (1) a method for manufacturing rapid energetic units with insensitivity, low energy input, and high energy output; (2) a method for manufacturing energetic fibers by combining energetic units; and (3) a method for achieving large-area laying of targets with complex curved surfaces using energetic fibers.

[0047] (1) A method for manufacturing a rapid energetic unit with low energy input and high energy output:

[0048] Manufacturing raw materials: insensitive oxides (such as hydroxylamine nitrate (HAN), including but not limited to HAN); titanium mesh; polymer materials (such as polyvinyl alcohol (PVA)), etc. The following steps are included:

[0049] a) Mixing the insensitive oxide with the polymer material to form a slurry, and ensuring that it can be cured at room temperature;

[0050] b) Press the titanium mesh and the insensitive oxide slurry into a fully bonded sheet by hot pressing, hot rolling, etc. Figure 4 As shown;

[0051] c) Titanium wires are connected to both ends of the sheet to form an energy-containing unit.

[0052] This method adopts a creative material formula and takes advantage of the characteristics of titanium material, which is stable at room temperature and active at high temperature, to create a fast energy-containing unit with good insensitivity and low input energy. It solves the industry pain point of high sensitivity of explosives in the field of energetic materials. The manufacturing method is simple and the ignition is reliable.

[0053] (2) A method for manufacturing energetic fibers by combining energetic units:

[0054] The following steps are involved:

[0055] a) Cutting the energetic sheet into designed small pieces;

[0056] b) Titanium wire is sewn onto the energetic sheet through a fixed line such as a polymer line, and the energetic fibers with energetic units arranged at intervals are manufactured through the linkage of rollers at both ends, and can be manufactured continuously, such as Figure 5 and 6 As shown;

[0057] c) Applying electricity to both ends of the energetic fiber can cause the entire energetic fiber to ignite;

[0058] This method combines energetic units with unique ignition mechanisms to form a whole energetic fiber, which retains the characteristics of the energetic units themselves while achieving ignition from point to line.

[0059] (3) A method for achieving large-area placement of targets with complex curved surfaces using energetic fibers:

[0060] The following steps are involved:

[0061] a) transporting the energetic fiber to a printing position via a roller;

[0062] b) making the energetic fibers slightly sticky by heating the module so that they can adhere to the target surface;

[0063] c) Through the continuous conveying of rollers and the cooperation of robotic arms, energetic fibers can be laid on a large area on targets with complex shapes, such as Figure 7-9 As shown;

[0064] d) The entire complex surface can be ignited synchronously by energizing both ends of the energetic fiber, such as Figure 9As shown;

[0065] This method places a special energetic fiber with ignition effect onto the target surface through a tape-laying process, which is a first in the field of energetic fibers. From line to surface, an ignition surface is formed that can ignite synchronously.

[0066] The following describes in detail the specific implementation of the energetic fiber and manufacturing method provided by the present invention that can realize synchronous ignition of large-area, arbitrarily complex curved surfaces through a specific embodiment.

[0067] Example 1

[0068] (1) Preparation of energetic sheets

[0069] The component contents of the energetic unit are: 54 wt.% hydroxylamine nitrate (HAN), 6 wt.% polyvinyl alcohol (PVA), and 40 wt.% titanium mesh.

[0070] Weigh 6g of PVA and add it to 54g of hydroxylamine nitrate (HAN) solution. Seal and let it stand overnight until PVA completely absorbs water and swells. Stir at a constant temperature of 70℃ for 6h until PVA is completely dissolved to obtain a PVA+HAN mixed solution. Pour it out while hot and put it into a storage container to fix the shape to obtain a PVA+HAN mixed gel. Weigh 6g of gel sample and 4g of titanium mesh, place the gel sample on the titanium mesh, and put them together in an aluminum plate mold. Adjust the temperature of the vulcanizer to 70℃ and hot press at a pressure of 5MPa for 5min. After hot pressing, put it into a low-temperature freezer together with the mold for freeze molding. Set the temperature to -20℃, freeze for 10h, thaw at 25℃, thaw for 5h, and take it out from the aluminum plate mold to obtain an energy-containing sheet ( Figure 4 ), thickness is 0.5mm.

[0071] (2) Preparation of energetic fibers

[0072] A device for preparing energetic fibers comprises a front roller 1, a sewing needle 4, a cutting knife 5, a rear roller 6, a positioning block 9, and a support plate 10; the front roller 1 and the rear roller 6 are arranged in parallel, and respectively comprise an upper roller and a lower roller, which are used for feeding and positioning a metal strip 7; the sewing needle 4, the cutting knife 5, and the positioning block 9 are located between the front roller 1 and the rear roller 6 and above the support plate 10; the positioning block 9 is used for positioning the metal strip 7; the support plate 10 is respectively provided with through holes cooperating with the cutting knife 5 and the sewing needle 4; the cutting knife 5 is used for cutting the metal strip 7 one by one to a set length of an energetic sheet 8; the sewing needle 4 is used for fixing the metal wire 2 to the energetic sheet 8.

[0073] The energetic fiber preparation device is used to prepare the energetic fiber, comprising the following steps:

[0074] 1) Metal strip feeding: The metal strip 7 is 8 mm wide and enters from the rear roller 6, passes through the positioning block 9, the cutting knife 5, the sewing needle 4 in sequence, and is bitten by the front roller 1;

[0075] 2) Wire fixing: The sewing needle 4 passes through the metal belt 7 and hooks the metal wire 2 below with the fixing line 3, fixing the metal wire 2 on the metal belt 7. With the continuous rotation of the front and rear rollers, the sewing needle 4 continues to move;

[0076] 3) Metal strip cutting: When the energetic unit reaches the set length of 15mm, the cutting blade 5 cuts the metal strip 7. After cutting, the front roller 1 rolls for a period of time to send the connected part a distance. This distance is the set length of the metal wire, the starting element of the energetic fiber, which is 5mm.

[0077] 4) Continuous feeding: The front and rear rollers then work simultaneously again, and the sewing needle 4 also starts working until the next energetic sheet reaches a set length, and this cycle is repeated to prepare an energetic fiber structure with alternating energetic sheets and starting elements.

[0078] (3) Energetic fiber placement and ignition

[0079] An ignition fiber placement device includes a roller 11, a support block 12, and a heating module 13. The roller 11 is used to position and transport the ignition fiber, the support block 12 is used to support the ignition fiber, and the heating module 13 is used to heat the ignition fiber.

[0080] The ignition fiber placement device is used to place the ignition fiber, and the following steps are included:

[0081] a) delivering the ignition fiber to the printing position of the ignition target 14 via the roller 11;

[0082] b) making the ignition fiber slightly sticky by the heating module 13 so that it can adhere to the surface of the energetic target 14;

[0083] c) Through the continuous transportation of the roller 11 and the cooperation of the robot arm, the energetic fiber is laid over a large area on the target 14 with a complex shape.

Claims

1. An energetic fiber capable of achieving synchronous ignition of large-area, arbitrarily complex curved surfaces, characterized in that: The energetic fiber is placed on a target surface with a complex curve using 3D printing; the energetic fiber comprises a plurality of energetic units, each of which is formed by connecting an energetic sheet and an energetic wire, wherein the energetic sheet is a combination of a titanium mesh and a passive oxide, and the energetic wire is a titanium wire; The production of the energy-containing sheet comprises the following steps: (11) mixing a passive oxide and a polymer material to form a slurry; the passive oxide is hydroxylamine nitrate, and the polymer material is polyvinyl alcohol; (12) The titanium mesh and the slurry are pressed into thin sheets by hot pressing or hot roller pressing to obtain an energetic sheet.

2. A method for manufacturing an energetic fiber capable of realizing synchronous ignition of a large area and arbitrary complex curved surface as claimed in claim 1, characterized in that: The following steps are involved: (1) Manufacturing energetic tablets; (2) Combining several energetic sheets and energetic filaments into energetic fibers; (3) Laying the energetic fiber onto the target surface with complex curves.

3. The manufacturing method according to claim 2, characterized in that The step (2) includes the following sub-steps: (21) Cutting the energetic sheet into the desired shape; (22) Titanium wires are sewn onto energetic sheets through fixed lines to continuously produce energetic fibers with energetic sheets and energetic wires arranged at intervals.

4. The manufacturing method according to claim 3, characterized in that Energetic fibers are prepared using an energetic fiber manufacturing device, the energetic fiber manufacturing device comprising a front roller, a sewing needle, a cutting knife, a rear roller, a positioning block, and a support plate; the front roller and the rear roller are arranged in parallel, respectively comprising an upper roller and a lower roller, and are used for feeding and positioning a metal strip; the sewing needle, the cutting knife, and the positioning block are located between the front roller and the rear roller and above the support plate; the positioning block is used for positioning the metal strip; through holes are respectively provided on the support plate for cooperating with the cutting knife and the sewing needle; the cutting knife is used for cutting the metal strip one by one to a set length of the energetic sheet; the sewing needle is used for fixing the titanium wire to the energetic sheet; The preparation process comprises the following steps: 1) Metal strip feeding: The metal strip enters from the rear roller, passes through the positioning block, cutting knife, sewing needle in sequence, and is bitten by the front roller; 2) Titanium wire fixing: The sewing needle passes through the metal belt and hooks the titanium wire below with a fixing line to fix the titanium wire on the metal belt. The sewing needle moves continuously with the continuous rotation of the front and rear rollers. 3) Metal strip cutting: When the metal strip reaches the set length of the energy unit, the cutting knife cuts the metal strip. After cutting, the front roller rolls for a set time to send the connected part out a set distance, which is the set length of the titanium wire. 4) Continuous feeding: The front and rear rollers then work simultaneously again, and the sewing needle also starts working until the next energetic sheet reaches a set length. This cycle is repeated to prepare an energetic fiber structure consisting of alternating energetic sheets and titanium wires.

5. The manufacturing method according to claim 3 or 4, characterized in that: The step (3) includes the following sub-steps: (31) transporting the energetic fiber to the printing position via a roller; (32) The energetic fiber is made sticky by a heating module so that it can adhere to the target surface; (33) Through the continuous conveying of rollers and the cooperation of robotic arms, energetic fibers can be laid over a large area on energetic targets with complex curved surfaces.

Images