Preparation method of HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder

Abstract

The invention discloses a preparation method of an HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder, and belongs to the technical field of energetic composite materials. Ti / Al mixed powder is pretreated and added into the HMX / RDX-based PBX explosive prepared by adopting a solution-water suspension method. The explosive has the characteristics of high energy release, low sensitivity and mechanical stability at the same time, the safety and stability in application are ensured, and the optimization and balance of the explosive performance are realized; by adding the titanium powder, pollutants released after combustion of the aluminum powder are reduced, and the green and environment-friendly characteristics of the explosive are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energetic composites, and particularly to a preparation method of an HMX / RDX-based PBX explosive with a low aluminum content containing Ti / Al mixed powder. Background Art

[0002] In the PBX explosive system, aluminum powder is often used as a fuel to improve the energy output and explosive power of the explosive. The aluminum powder burns instantaneously during explosion and reacts with the detonation products and environmental oxygen to generate high-temperature and high-pressure gases. However, there are still the following problems in the application of aluminum powder: 1) Formation of oxide film: An oxide film is easily formed on the surface of aluminum powder, reducing its activity, affecting the ignition performance, and increasing the ignition delay time; 2) Particle agglomeration phenomenon: During the reaction process, aluminum powder is prone to agglomeration, resulting in uneven combustion and affecting the energy release efficiency; 3) Stability of PBX explosive with low aluminum content: Reducing the aluminum content may reduce the explosive performance of the PBX explosive, making it unable to achieve the expected effect under specific environmental conditions.

[0003] In contrast, the application of titanium powder in the explosive system shows certain advantages: 1) Excellent antioxidant performance: Titanium is not easily oxidized, which can improve the long-term storage performance and thermal stability of the explosive; 2) Reducing environmental pollution: Compared with aluminum powder, titanium powder has lower environmental pollution during the explosion process.

[0004] However, there are also certain problems in the use of titanium powder, such as a relatively large density and easy detachment from the PBX explosive matrix, which may lead to an increase in mechanical sensitivity and affect the overall performance of the explosive. Therefore, it is necessary to explore an optimized Ti / Al mixed powder system that takes into account low sensitivity, high energy, and environmental friendliness to improve the comprehensive performance of the PBX explosive. Summary of the Invention

[0005] The present invention discloses a preparation method of an HMX / RDX-based PBX explosive with a low aluminum content containing Ti / Al mixed powder, which solves the above problems. The PBX explosive prepared by this method has both low sensitivity and high energy, and at the same time, the preparation method is green and environmentally friendly.

[0006] The present invention discloses a preparation method of an HMX / RDX-based PBX explosive with a low aluminum content containing Ti / Al mixed powder, comprising the following steps:

[0007] S1. Pretreatment of Ti / Al mixed powder: At 95 °C, stir the Ti powder, Al powder, and paraffin evenly under the action of an ultrasonic cleaner, then stop heating, and let the mixture cool naturally until there is no wet phenomenon on the surface, and then spread it out for cooling to improve the uniformity and dispersibility of the powder and prevent agglomeration;

[0008] S2. Preparation of the bonding system: Dissolve the F2604 binder in analytical pure ethyl acetate to prepare a uniform bonding system solution to ensure the stable coating of subsequent explosive particles.

[0009] S3. Preparation of the HMX / RDX suspension: Disperse in water according to the ratio of HMX:RDX = 6:4 - 5:5 to form a uniform HMX / RDX suspension.

[0010] S4. Addition and mixing of the bonding system: Slowly add the bonding system solution to the HMX / RDX suspension under continuous stirring.

[0011] S5. Formation of PBX explosive particles: Stir the mixture in S4 for 1 - 2 hours. After the solvent has completely evaporated, sieve through a 30 - mesh sieve to form PBX explosive particles with a particle size of 0.5 mm - 1.0 mm.

[0012] S6. Introduction of Ti / Al powder: At 95 °C, add the pretreated Ti / Al mixed powder and paraffin to the PBX explosive particles, and continuously stir for 30 minutes to ensure the uniform dispersion of the Ti / Al powder, obtaining an HMX / RDX - based low - aluminum - content PBX explosive containing the Ti / Al mixed powder.

[0013] Preferably, in step S1, the particle sizes of both the Ti powder and the Al powder are 15 μm, and the Ti powder, Al powder, and paraffin are mixed according to the mass ratio of Ti:Al:paraffin = 3:6:1 - 5:4:1.

[0014] Preferably, in step S2, the binder is fluororubber (F2604), and the mass ratio of the F2604 binder to analytical pure ethyl acetate is 1:(5 - 8).

[0015] Preferably, in step S4, the addition mass ratio of the bonding system solution to the HMX / RDX suspension is 1:(6 - 15).

[0016] Preferably, in step S6, the addition mass ratio of the Ti / Al mixed powder, HMX / RDX in the PBX explosive particles, and paraffin is (4.95 - 9.9):(95 - 90):(0.05 - 0.2).

[0017] The present invention also discloses an HMX / RDX - based low - aluminum - content PBX explosive containing the Ti / Al mixed powder prepared by the above - mentioned preparation method. The HMX / RDX - based low - aluminum - content PBX explosive includes the following components and their mass percentages: HMX: 30 - 60%, RDX: 30 - 60%, binder: 5 - 10%, Ti: 3% - 6%, Al: 1 - 4%, paraffin: 0.5 - 2%.

[0018] Therefore, the present invention provides a preparation method of an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder, having the following beneficial effects:

[0019] (1) By precisely controlling the Ti / Al ratio, the explosive simultaneously possesses high energy release characteristics (from aluminum) and low sensitivity and mechanical stability (from titanium), ensuring safety and stability during application and achieving optimization and balance of the explosive performance;

[0020] (2) The ultrasonic cleaning + natural cooling pretreatment process is adopted to effectively remove impurities and oxide layers on the surface of the Ti / Al mixed powder. Meanwhile, by utilizing the cavitation effect of ultrasonic waves, the powder particles are fully dissociated and evenly distributed in the liquid medium, effectively improving the uniform dispersion of the Ti / Al mixed powder and reducing the risk of agglomeration. Subsequently, through the natural cooling method, the thermal stress or structural damage that may be caused by rapid cooling is avoided, ensuring the stability of the physical and chemical properties of the powder particles. This pretreatment process can not only reduce the agglomeration risk of the Ti / Al mixed powder but also improve its interfacial bonding state, enhancing the overall energy release efficiency of the explosive;

[0021] (3) Appropriate use of Ti powder reduces the pollutants released after the combustion of aluminum powder and improves the green environmental protection characteristics of the explosive. Specifically, titanium elements have high chemical stability and can effectively inhibit the harmful by-products generated by the excessive reaction of aluminum powder with oxygen during the explosion reaction process, reducing the emissions of soot, heavy metal particles, and other toxic substances. Description of the Drawings

[0022] Figure 1 Particles of the HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder prepared in Example 1 of the present invention;

[0023] Figure 2 The explosive column of the HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder prepared in Example 1 of the present invention;

[0024] Figure 3 Particles of the HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder prepared in Example 2 of the present invention;

[0025] Figure 4 The explosive column of the HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder prepared in Example 2 of the present invention;

[0026] Figure 5 Particles of the HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder prepared in Example 3 of the present invention;

[0027] Figure 6The HMX / RDX-based PBX explosive charge with low aluminum content containing Ti / Al mixed powder prepared in Example 3 of the present invention. Detailed implementation manners

[0028] The present invention will be further described below through specific examples, but it should be understood that these examples are only for more detailed description and should not be construed as limiting the present invention in any form, that is, it is not intended to limit the protection scope of the present invention.

[0029] The present invention discloses a preparation method of an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder, comprising the following steps:

[0030] S1. Pretreatment of Ti / Al mixed powder: At 95 °C, Ti powder, Al powder, and paraffin are stirred evenly by an ultrasonic cleaner and then the heating is stopped. The mixture is allowed to cool naturally until there is no wet phenomenon on the surface and then spread out for cooling to improve the uniformity and dispersibility of the powder and prevent agglomeration.

[0031] S2. Preparation of binder system: The binder is dissolved in analytical pure ethyl acetate to prepare a uniform binder system solution to ensure the stable coating of subsequent explosive particles.

[0032] S3. Preparation of HMX / RDX suspension: Dispersed in water according to the mass ratio of HMX:RDX = 6:4 to 5:5 to form a uniform HMX / RDX suspension.

[0033] S4. Addition and mixing of binder system: Under continuous stirring, the binder system solution is slowly added to the HMX / RDX suspension.

[0034] S5. Formation of PBX explosive particles: The mixture in S4 is stirred for 1 - 2 hours. After the solvent is completely volatilized, it is sieved through a 30-mesh sieve to form PBX explosive particles with a particle size of 0.5 mm - 1.0 mm.

[0035] S6. Introduction of Ti / Al powder: At 95 °C, the pretreated Ti / Al mixed powder and paraffin are added to the PBX explosive particles and continuously stirred for 30 minutes to ensure the uniform dispersion of the Ti / Al powder, obtaining an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder.

[0036] Specifically, in step S1, the particle sizes of both Ti powder and Al powder are 15 μm, and Ti powder, Al powder, and paraffin are mixed according to the mass ratio of Ti:Al:paraffin = 3:6:1 to 5:4:1.

[0037] In step S2, the mass ratio of the binder to analytical pure ethyl acetate is 1:(5 - 8).

[0038] In step S4, the mass ratio of the bonding system solution to the HMX / RDX suspension is 1:(6 - 15).

[0039] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0040] Example 1

[0041] This example provides an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder, and its mass content components are: HMX: 44.5%, RDX: 44.5%, CAB: 5%, Ti: 1.7%, Al: 3.3%, paraffin: 1%. Its preparation method includes the following steps:

[0042] (1) At 95 °C, add Ti powder (15 μm), Al powder (15 μm), and paraffin in the ratio of Ti:Al:paraffin = 3 g:6 g:1 g. Stir for 3 h under the action of an ultrasonic cleaner, and let the mixture cool naturally until there is no wet phenomenon on the surface, then spread it out for cooling to improve the uniformity and dispersibility of the powder and prevent agglomeration.

[0043] (2) Weigh 5 g of F2604 with a balance and put it into a bottle, add 30 g of ethyl acetate, then seal the bottle mouth and place it at room temperature for 20 h to completely dissolve it.

[0044] (3) Weigh 45 g of HMX and 45 g of RDX with a balance and put them into a beaker, and disperse them in 200 ml of water in the ratio of HMX:RDX = 1:1 to form a uniform suspension.

[0045] (4) Set the water bath temperature to 70 °C and the stirring speed to 400, then drop the bonding system solution into the beaker at a speed of 10 ml / min to coat HMX and RDX. After all the binder solution is dropped, drive the solvent for 1 h to completely remove ethyl acetate and form a stable PBX explosive matrix.

[0046] (5) Then put the prepared TI / Al mixed powder, PBX explosive matrix, and paraffin into a dry beaker in the ratio of 5.5 g:94 g:0.5 g, and place it in a water bath at 90 °C and stir for 1 - 2 hours, and sieve through a 30-mesh sieve to form an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder.

[0047] The morphology of the HMX / RDX-based PBX explosive with low aluminum content prepared in this example is asFigure 1 As shown, the particles are grayish-black and approximately oval in shape, with a diameter of about 1-2 mm. The particles are prepared into a charge, as Figure 2 shown, with dimensions of φ25×25.

[0048] (1) Perform performance tests on the charge. The measured density of the charge is 1.800-1.810 g / cm 3 , and the theoretical density is 1.846 g / cm 3 , reaching 97.6-98% of the theoretical density.

[0049] (2) The measured detonation velocity of the explosive is 8366 m / s (1.80 g / cm 3 ), and the heat of detonation is 6012 KJ / Kg, with excellent performance.

[0050] (3) The impact sensitivity is 8 (%), and the friction sensitivity is 14 (%), with low sensitivity and good safety performance.

[0051] Example 2

[0052] This example provides an HMX / RDX-based PBX explosive with low aluminum content containing Ti / Al mixed powder, and its content components are: HMX: 42%, RDX: 42%, F2604: 4%, Ti: 6%, Al: 3%, paraffin: 2%. Its preparation method includes the following steps:

[0053] (1) At 95 °C, add Ti powder (15 μm), Al powder (15 μm), and paraffin in the ratio of Ti:Al:paraffin = 6 g:3 g:1 g. Stir for 3 h under the action of an ultrasonic cleaner, and let the mixture cool naturally until there is no wetting phenomenon on the surface, then spread it out to cool, so as to improve the uniformity and dispersibility of the powder and prevent agglomeration.

[0054] (2) Use a balance to weigh 5 g of F2604 into a bottle, add 30 g of ethyl acetate, and then seal the bottle mouth and place it at room temperature for 20 h to completely dissolve.

[0055] (3) Use a balance to weigh 45 g of HMX and 45 g of RDX into a beaker, and disperse them in 200 ml of water in the ratio of HMX:RDX = 1:1 to form a uniform suspension.

[0056] (4) Set the water bath temperature to 70 °C and the stirring speed to 400, and then drop the binder system solution into the beaker at a speed of 10 ml / min to coat HMX and RDX. After all the binder solution is dropped, drive off the solvent for 1 h to completely remove ethyl acetate and form a stable PBX explosive matrix.

[0057] (5) Then, the prepared TI / Al mixed powder, PBX explosive matrix, and paraffin are put into a dry beaker in a ratio of 11 g:88 g:1 g, and placed in a water bath at 90 °C and stirred for 1 to 2 hours. After passing through a 30-mesh sieve, an HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder is formed.

[0058] The morphology of the HMX / RDX-based low-aluminum-content PBX explosive prepared in this example is as Figure 3 shown. The morphology is grayish-black, approximately elliptical particles with a diameter of about 1 - 2 mm. The particles are prepared into a charge, as Figure 4 shown, with dimensions of φ40×40.

[0059] (1) Perform performance tests on the charge. The measured density of the charge is 1.830 - 1.8340 g / cm 3 , and the theoretical density is 1.88 g / cm 3 , reaching 97 - 97.5% of the theoretical density.

[0060] (2) The detonation velocity of the explosive is 8265 m / s (1.83 g / cm 3 ), and the heat of detonation is 6132 KJ / Kg, with excellent performance.

[0061] (3) The impact sensitivity is 12 (%), and the friction sensitivity is 20 (%), with low sensitivity and good safety performance.

[0062] Example 3

[0063] This example provides an HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder, and its component contents are: HMX: 58.1%, RDX: 33.2%, F2604: 5%, Ti: 8%, Al: 2%, paraffin: 1%, graphite: 1%. Its preparation method includes the following steps:

[0064] (1) Under the condition of 95 °C, add Ti powder (15 μm), Al powder (15 μm), and paraffin in a ratio of Ti:Al:paraffin = 8 g:2 g:1 g. Stir for 3 h under the action of an ultrasonic cleaner, and let the mixture cool naturally until there is no wet phenomenon on the surface, then spread it out for cooling to improve the uniformity and dispersibility of the powder and prevent agglomeration.

[0065] (2) Weigh 5 g of F2604 with a balance and put it into a bottle, add 30 g of ethyl acetate, then seal the bottle mouth and place it at room temperature for 20 h to make it completely dissolve.

[0066] (3) Weigh 50 g of HMX and 33 g of RDX with a balance and put them into a beaker, and disperse them in 200 ml of water in a ratio of HMX:RDX = 3:2 to form a uniform suspension.

[0067] (4) Set the water bath temperature to 70 °C and the stirring speed to 400. Then, add the binder system solution dropwise into the beaker at a rate of 10 ml / min to coat HMX and RDX. After all the binder solution has been added, remove the solvent for 1 h to completely remove ethyl acetate and form a stable PBX explosive matrix.

[0068] (5) Then, put the prepared TI / Al mixed powder, PBX explosive matrix, and graphite into a dry beaker in a ratio of 11 g:88 g:1 g, and place it in a water bath at 90 °C and stir for 1 - 2 hours. Pass through a 30-mesh sieve to form an HMX / RDX-based PBX explosive with a low aluminum content containing the Ti / Al mixed powder.

[0069] The morphology of the HMX / RDX-based PBX explosive with a low aluminum content prepared in this example is as Figure 5 shown. The morphology is black, approximately oval-shaped particles with a diameter of about 1 - 2 mm. Prepare the particles into a charge, as Figure 6 shown, with dimensions of φ40×40.

[0070] (1) Conduct performance tests on the charge. The measured density of the charge is 1.824 - 1.838 g / cm 3 , and the theoretical density is 1.880 g / cm 3 , reaching 97 - 97.7% of the theoretical density.

[0071] (2) The detonation velocity of the explosive is 8086 m / s (1.824 g / cm 3 ), and the heat of detonation is 6239 KJ / Kg, with excellent performance.

[0072] (3) The impact sensitivity is 8 (%), and the friction sensitivity is 24 (%), with low sensitivity and good safety performance.

[0073] In summary, the preparation method of an HMX / RDX-based PBX explosive with a low aluminum content containing Ti / Al mixed powder disclosed in the present invention enables the explosive to simultaneously possess high energy release characteristics, low sensitivity, and mechanical stability, ensuring safety and stability in applications and achieving optimization and balance of explosive performance; moreover, by adding titanium powder, the pollutants released after the combustion of aluminum powder are reduced, improving the green environmental protection characteristics of the explosive.

[0074] The above specific embodiments further illustrate the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and do not limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder, characterized in that: The following steps are involved: S1. Pretreatment of Ti / Al mixed powder: at 95°C, stir Ti powder, Al powder and paraffin in an ultrasonic cleaning machine and then stop heating. Allow the mixture to cool naturally until the surface is free of moisture and then spread out to cool. S2, preparation of bonding system: dissolving the bonding agent in ethyl acetate to prepare a uniform bonding system solution; S3. Preparation of HMX / RDX suspension: Disperse in water at a mass ratio of HMX:RDX=6:4-5:5 to form a uniform HMX / RDX suspension; S4. Adding and mixing the bonding system: slowly adding the bonding system solution into the HMX / RDX suspension under continuous stirring; S5, PBX explosive particle formation: Stir the mixed product in S4 for 1 to 2 hours, wait for the solvent to evaporate completely, and sieve through 30 mesh to form PBX explosive particles with a particle size of 0.5 mm to 1.0 mm; S6. Introduction of Ti / Al powder: at 95°C, add pretreated Ti / Al mixed powder and paraffin wax to the PBX explosive particles and continue stirring for 30 minutes to obtain HMX / RDX-based low aluminum content PBX explosive containing Ti / Al mixed powder.

2. The method for preparing a HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder according to claim 1, characterized in that: In step S1 , the particle sizes of Ti powder and Al powder are both 15 μm, and Ti powder, Al powder and paraffin are mixed in a mass ratio of Ti:Al:paraffin=3:6:1 to 5:4:

1.

3. The method for preparing a HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder according to claim 1, characterized in that: In step S2, the binder is fluororubber, and the mass ratio of the binder to ethyl acetate is 1:(5-8).

4. The method for preparing a HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder according to claim 1, characterized in that: In step S4, the mass ratio of the bonding system solution to the HMX / RDX suspension is 1:(6-15).

5. The method for preparing a HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder according to claim 1, characterized in that: In step S6, the mass ratio of the Ti / Al mixed powder, HMX / RDX in the PBX explosive particles and paraffin is (4.95-9.9):(95-90):(0.05-0.2).

6. The method for preparing a HMX / RDX-based low-aluminum PBX explosive containing Ti / Al mixed powder according to claims 1-5, characterized in that: A HMX / RDX-based low-aluminum-content PBX explosive prepared by the preparation method according to any one of claims 1 to 5.

7. The method for preparing a HMX / RDX-based low-aluminum-content PBX explosive containing Ti / Al mixed powder according to claim 6, characterized in that: The HMX / RDX-based low-aluminum PBX explosive includes the following components and their mass percentages: HMX: 30-60%, RDX: 30-60%, binder: 5-10%, Ti: 3%-6%, Al: 1-4%, paraffin: 0.5-2%.

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