CHINESE JOURNAL OF ENERGETIC MATERIALS
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  • PDF HTML Export Preparation and Properties of Al/Bi2O3-HNIW Hybrid Composites
    CJEM | 2020No.12
  • Double-nozzle Microjet Direct Writing and Properties of CL-20 Based Energetic Film
    CJEM | 2020No.11
  • Damage-ignition Simulation for Typical Pressed and Casted PBX under Crack-extruded Loading
    CJEM | 2020No.10
  • Thermodynamic on the Formation of CL-20/1,4-DNI Cocrystal
    CJEM | 2020No.9
  • Preparation and Reaction Characteristics of Spherical Al-Si Alloy Fuel
    CJEM | 2020No.8
  • Synthesis and Thermal Stability of 4-Azido-2,2,6,6-tetranitroadamantane
    CJEM | 2020No.7
  • Synthesis, Characterization and Hygroscopicity Testing of Molecular Perovskite Energetic Materials
    CJEM | 2020No.6
  • Preparation and Catalytic Combustion of JP‑10 Based Pt Nanofluid Fuels Stabilized by Hyperbranched Polymer
    CJEM | No.5, 2020
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    • ZHAI Cheng-lin, CHEN Xiao-wei

      Online:December 28, 2020  DOI: 10.11943/CJEM2020316

      Abstract:With the deepening and development of the concept of long-range operations, long-range strike missile has become an indispensable part of modern warfare. Therefore, the damage assessment of target hit by missile warhead has been the focus of damage research in recent years. Research of damage assessment in the process of missile warhead striking the target are summarized from four aspects: damage assessment model of target, main subjects in damage process, classification of target damage, and methods of damage assessment, respectively. Problems such as non-standard judgment of damage degree, unclear relationship of damage mapping and inaccurate solution of damage probability in current stage are pointed out. According to the insufficiency of current study, some suggestions are proposed for the research in the future, which can provide reference for the investigations in the related fields.

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    • SONG Xian-zhao, JIANG Jun, AN Gao-jun, WANG Yong-xu, CUI Sai-nan, LI Bin, XIE Lie-feng

      Online:January 11, 2021  DOI: 10.11943/CJEM2020223

      Abstract:To explore the liquid components of high-potential Fuel air explosive(FAE) with better damage power, taking the traditional typical fuel (propylene oxide) as reference, polymethoxy dibutyl ethe(BTPOMn), polymethoxy dimethyl ether (DMM2), 1-butanol and 2-butyl alcohol were selected as research object. A pressure testing system, high-speed camera and infrared thermal image were used to record the experimental data. The cloud explosive characteristics of the 5 fuels with 18g RDX as central burster charge and 160g TNT as secondary explosive were studied. The results indicated that the critical initiation energy of the DMM2was higher than that of the other fuels. The relationship of the damage radius of thermal radiation among 5 fuels was as follows: propylene oxide (18.9 m)>2-butyl alcohol (16.6 m)>1-butanol (16.0 m)>DMM2 (15.6 m)>BTPOMn (12 m). The damage effects of 5 fuels on people and buildings were evaluated by the PROBIT equation, and the results showed that the damage effects of 1-butanol and 2-butyl alcohol were better than those of BTPOMn and DMM2, and the propylene oxide had the best damage effect.

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    • LIU Sai, SHI Wei, WANG Yi, ZHANG Qinghua

      Online:December 16, 2020  DOI: 10.11943/CJEM2020228

      Abstract:Due to conjugated planar molecular structure and additional N-oxide bonds, nitrogen-rich fused-ring N-oxides usually exhibit the advantages of high density, good detonation performances and good sensitivity and they have gradually become a research hotspot of energy materials. This article reviewed molecular structure, synthesis method and physical and chemical properties of twenty nitrogen-rich fused-ring N-oxides that were synthesized in the last decade. At the same time, this article compared some main physical and chemical properties between nitrogen-rich fused-ring N-oxides and their precursors. This review will provide some references for the synthesis and property investigation of new nitrogen-rich fused-ring N-oxides.

    • JIANG Shuai, LIU Qiong, NAN Feng-qiang, YIN Ji-hong, DU Ping

      Online:December 25, 2020  DOI: 10.11943/CJEM2020252

      Abstract:In order to understand the constant volume combustion performance of single charge and the mixed charge(MC+B) of 37-hole nitroguanidine propellant, a lace-shaped 37-hole triguanidine-15 propellant is used as the main charge (MC), and the lace-shaped 19-hole triguanidine-15 coated propellant is used as the auxiliary charge(B). The packing density is 0.20 g·cm-3, under 50 ℃, 20 ℃, -40 ℃, the effect of arc thickness on the combustion performance of single main charge and the effect of the mixing mass ratios on the combustion performance of the mixed charge (MC+B) were studied through constant volume closed-bomb test. The results show that the lower the temperature, the more obvious the erosion and combustion phenomenon of the 37-hole single main charge. At the same temperature, the greater the arc thickness of the main charge, the less obvious the erosion and combustion phenomenon, the stronger the progressive combustion, and the better the combustion performance. The higher the temperature, the greater the value of ΔLLm/L0 of the mixed charge of the same mixing ratio, the better the progressive combustion; At the same temperature, the progressive combustion of the mixed charge is stronger than that of the single main charge, and as the ratio of the coated propellant increases, the erosion combustion peak gradually decreases, indicating that the addition of the coated propellant significantly improves the progressive combustion and reduces the erosion combustion peak of the mixed charge, and at 50 ℃, 20 ℃, -40 ℃, the mixing ratio of the mixed charge to obtain better progressive combustion is 7∶3.

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    • CUI Tao, LIU Zhi-han, XIE Wei, XUE Xiang-gui

      Online:December 25, 2020  DOI: 10.11943/CJEM2020174

      Abstract:Molecular dynamics simulation is an important method to predict the shock sensitivity of energetic materials, while it is computationally expensive and force fields may be unavailable for some energetic materials. Here, an algorithm was designed and implemented in a computer program in Python for calculating the Steric Hindrance Index (SHI), which is a descriptor for evaluating shock sensitivity. The algorithm 1) compresses the crystal unit cell of an energetic material keeping the molecular unit rigid to simulate deformation under shock; 2) establishes a new rectangular coordinate system for the specific slip system and rotates the cell to deal with general shock directions and slip systems; 3) assigns molecular units to layers based on the coordinate of their centroid; 4) calculates the overlapped area of each two adjacent layers after projection along the slip direction; and 5) obtains SHI by normalization of overlapped areas. For PETN, BTF, RDX, and TNT at a compression ratio of 0.1, the calculated average SHI are 0.8707, 0.7940, 0.4228, and 0.0924, respectively, which is consistent with the decreasing order of impact sensitivity mentioned in references. SHI classifies the slip systems in line with those based on molecular dynamics simulations, yet with better computing efficiency and methodological applicability.

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    • GONG Zheng, TU Xiao-zhen, ZENG Gui-yu, BAI Liang-fei, CAO Ke

      Online:December 25, 2020  DOI: 10.11943/CJEM2020152

      Abstract:To gain insights into the stability of nano TATB in different storage environments, aging conditions at 90 ℃, 10%RH, 50%RH, 90%RH and 200 Pa low atmospheric pressure were considered. The microstructure evolution of nano TATB was characterized by small angel neutron scattering (SANS), scanning electron microscope (SEM), X-ray diffraction (XRD), Raman spectroscopy (Raman) and infrared spectroscopy (IR). Results show that the specific surface area of nano TATB decreases obviously after the thermal aging at 45 ℃, 60 ℃ and 71 ℃, and the higher the aging temperature, the more obvious the specific surface area decreases, accompanied by the growth of some crystal particles. The long-term stability of nano TATB crystal particles is significantly affected by the extreme humidity and heat environment (90 ℃, 90% RH). After short-term storage (5 days), the nano TATB particles grow up with the size of about 1-3 μm. The nano TATB particles also grow and form a micro flake structure after aging in a low pressure (200 Pa) environment at 90 ℃. Based on the experiment results, the growth and aging mechanism of nano TATB were discussed. The high surface energy of nano TATB facilitates TATB molecules overcoming the energy barrier, which results in the TATB molecules diffusion and rearrangement on the crystal surface and correspondingly leads to the grow-up of particles.

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    • WU Peng, LI Gao-chun, HAN Yong-heng, WANG Zhe-jun, QIAN Ren-jun

      Online:December 25, 2020  DOI: 10.11943/CJEM2020096

      Abstract:In order to study the damage and failure process of adhesive interface of solid rocket motor, rectangular adhesive specimen of solid rocket motor was made based on QJ2038.1A-2004 regulation standard and tensile tests was carried out. The damage and failure mode of the adhesive interface specimen was obtained. The parameter inverse identification method which is based on step inverse and Hooke-Jevees optimization algorithm was adopted. The relevant parameters of the bilinear cohesive model of mix mode at the propellant/liner/insulator interface were obtained and were applied into the numerical simulation of the damage and failure process of adhesive specimen in tensile tests. Results show that the main failure form of adhesive interface specimen is the debonding at the interface of the propellant/liner/insulator layer; the proposed parameter inverse identification method can obtain the interface parameters of solid rocket motors well. The initial modulus, maximum bonding strength and fracture energy of the propellant/liner/insulator layer of solid rocket motors are 0.86 MPa, 0.63 MPa and 3.13 kJ·m-2 at tension speed of 2 mm·min-1, respectively. The damage of the propellant/liner/insulation layer interface makes the increase rate of stress decrease with the tensile strain. The initiation interface crack at the tip of the artificial debonding layer and the expansion along the center of the specimen, and finally penetration of the bonded specimen is the main damage and failure mode of the adhesive specimen.

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    • WANG Jing-kai, CHEN Jie, SUI He-liang, YU Qian, YANG Xiu-lan, SUO Zhi-rong, SUN Jie, YIN Ying

      Online:December 24, 2020  DOI: 10.11943/CJEM2020146

      Abstract:The oxidation reaction of micro and nano aluminum powder is an important way of energy release and aging inactivation. Molecular dynamics and reaction kinetics provide necessary means for elucidating the microscopic mechanism of oxidation reaction of aluminum powder and quantitatively describing the oxidation process. According to the type of reaction system, the oxidation of aluminum powder can be divided into aluminum-oxygen (Al-O2), aluminum-water (Al-H2O) and aluminum-other oxides (Al-other oxides) reaction systems. The recent progress of molecular dynamics and reaction kinetics in the above reaction systems is reviewed. The mechanism of oxidation kinetics of aluminum powder and its key influencing factors, including the oxide layer, particle size, atomic diffusion rate, temperature and oxygen concentration, were discussed, which proved the flexibility and effectiveness of molecular dynamics and reaction kinetics. On this basis, the important problems in different oxidation reaction systems were analyzed and prospected. It is pointed out that the oxidation kinetics of aluminum powder under multiple factors, the kinetics of Al-water vapor reaction, and the intrinsic mechanism of Al-other oxides reaction are the key problems to be solved in the future.

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    • LIU Guang-kun, LIU Rui-chao, WANG Wei, WANG Xing, ZHAO Qiang

      Online:December 24, 2020  DOI: 10.11943/CJEM2020281

      Abstract:As the arch structure is one of the common structural forms of underground engineering, the majority of current research focuses on the numerical simulation. The numerical results of structural damage characteristics and response lack corresponding experimental verification, which cannot sufficiently guide the blast resistance design of underground engineering. In order to study the failure mode and blasting resistant performance of underground arch structures with reinforced concrete under explosive load, 5 independent experiments under top explosion had been carried out with different blasting distances and charges. Results show that the damage degree of the arch structure gradually increases with the increase of charge under the same blasting distance. The characteristics of failure mode developed from the concrete cracks at the back surface of blast to the concrete spalling and deformation of steel bars. At last, the concrete collapsed significantly at the center of the vault and the steel bars were severely bent and deformed. The damage of the arch structure under top explosion is not only related to the scaled distance, but also affected by the blasting distance. Under the same scaled distance, the more the blasting distance is, the more significant the damage of arch structure is. By analyzing the relationships between the displacement response and the charge mass, the displacement response and the blasting distance, a method is initially proposed for dividing the damage grade based on the deflection-span ratio, which provides experimental support for the structural failure evaluation and analysis in the future.

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    • WANG Yu-ting, HUANG Zheng-xiang, JIA Xin, MA Bin, ZU Xu-dong, XIAO Qiang-qiang

      Online:December 09, 2020  DOI: 10.11943/CJEM2020276

      Abstract:To study the jet formation and penetration characteristics of the shaped charge with elliptical cross-section, and the influence of the ratio of long axis to short axis at a fixed short axis, DOP (Depth of Penetration) tests at stand-off 80 mm were carried out for shaped charges with elliptical cross-section. The short axis diameter of elliptical cross-section is 56 mm and the ratio of long axis to short axis are 1, 1.5 and 2, respectively. By using ANSYS/LS-DYNA software to construct related finite element models, the jet formation and penetration process are simulated numerically. The results showed that except for the jet head, the rest of jet was cohesionless at the late stage of stretching. The non-condensed part of jet consists of two fluids with lateral velocity symmetrically distributed over the section of long axis. The non-condensation of jet will significantly reduce the penetration ability of the shaped charge with elliptical cross-section. For the shaped charge with a short axis diameter of 56 mm, the penetration depth decreased by 68.3% from 150 mm to 47.5 mm when the ratio of long axis to short axis changed from 1 to 1.5, while no significant change of penetration ability occurred while the ratio of long axis to short axis changed from 1.5 to 2.

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    • LI Chang-lin, GAN Qiang, FENG Chang-gen, HU Jing-wei, ZHU Shuang-fei, CHENG Nian-shou

      Online:December 15, 2020  DOI: 10.11943/CJEM2020157

      Abstract:In order to analyze high temperature phase transformation of hexanitrohexaazaisowurtzitane (CL-20), phase transformation temperatures and coefficients of thermal expansion of ε-、β- and γ-CL-20 were studied via ReaxFF-lg reactive force field molecular dynamics, with modified valence potential intercept. To validate the applicability of selected force field,the density, cell constant, lattice energy, and sublimation enthalpy of three types of CL-20 at room temperature were calculated. The third order Birch-Murnaghan equation of state was used to fit the p-V curve of ε-CL-20, with pressure ranging from 0 to 280 GPa. And the variation of bulk modulus (B0) and its partial derivative to pressure (B0) with the increase of pressure is analyzed. High temperature phase transformation analysis shows that ε-and γ-CL-20 change phases at 398-423 K, of which the ε→γ phase transition occurs at atmospheric pressure, while the γ→ε phase transition needs 0.5 GPa or higher pressure; β-CL-20 transforms to ε crystal form at 448 K. The thermal expansion coefficient analysis shows that there is no obvious anisotropy in the high temperature thermal expansion process of ε-CL-20, while β- and γ-CL-20 show anisotropy in c direction and b direction, respectively. Results show that the modified ReaxFF-lg reactive force field is suitable for the study of phase transition of ε- β- and γ-CL-20 at high temperature and high pressure, while the accuracy of thermal expansion of β- and γ-CL-20 needs to be further improved.

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    • ZHAO Xiang-run, YAN Nan, GUO Chong-xing, DAI Wu-si, YAN Li-wei, JIN Shi-xin

      Online:December 11, 2020  DOI: 10.11943/CJEM2020129

      Abstract:In order to prevent the spacecraft from being damaged due to the high pyroshock of the separation nut, an orifice is used to suppress the pyroshock response of the separation nut during separation. Throttle holes with three diameters of Φ2 mm, Φ4 mm and Φ6 mm are set on the powder gas channel of the separation nut. The pressure, acceleration and preload of the separation nuts of different orifices in the separation process are tested simultaneously, so as to analyze the separation process of the separation nuts. According to the sequence of movement, the pyroshock load is decoupled into three types of pyroshock sources: powder combustion, preload release and piston impact. The time-acceleration (a-t) curve is transformed into a shock response spectrum (SRS), and the contribution of each shock source is calculated. The relationship between the orifice diameter and the shock response is obtained. The results show that in the frequency domain of 500 to 10000 Hz, the contribution of gunpowder action is 8.3% to 11.0%; the contribution of preload release is 44.0% to 51.5%; and the contribution of piston impact is 40.2% to 45.0%. The maximum pyroshock response during the separation process is: 1416 g (Φ6 mm), 1251 g (Φ4 mm) and 852 g (Φ2 mm). It can be seen that the use of the orifice can effectively suppress the impact response of the separation nut.

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    • SHEN Bo, LI Yan

      Online:December 02, 2020  DOI: 10.11943/CJEM2020256

      Abstract:To achieve an effective evaluation of the damage power of all-energetic penetration warhead, a test system for damage power assessment was established based on the 125mm artillery, accompany by a description in multiple physical fields from various aspects such as penetration, reaming, high temperature, high pressure, and arson ignition by arson. Results show that a 16 kg warhead can penetrate a 5-layered steel target at a speed of 952 m·s-1 to form strong fire which lasts for about 120 ms, with a maximum diffusion range of over 6 m×10 m and a maximum temperature of about 2100 ℃. Compared with the inert warhead, the gains of temperature and overpressure at 1.2 m are about 1270 ℃ and 0.16-0.5MPa, respectively, and the cumulative gain of the broken hole area of 5-layered steel target reaches beyond 300%. Moreover, the warhead has a good arson ignition effect on the fuel tank.

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    • CHEN Si-min, HUANG Zheng-xiang, JIA Xin, XIA ming, WANG Jian-hui, XIAO Qiang-qiang, TANG De-rong

      Online:November 18, 2020  DOI: 10.11943/CJEM2020260

      Abstract:To study the initiation process under jet impact and obtain the critical initiation threshold of explosives with different thicknesses, experiments of jet formation with Φ40 mm shaped charge were performed and captured by the high-speed video. The 43 mm thick TNT explosives were covered by 50SiMnVB cover plates with different thicknesses in experiments. The critical initiation threshold, the response under different stimulus intensities and the expansion velocity of reaction products were obtained. The numerical simulation of finite-thickness explosive under jet impact was carried out by using numerical simulation software. The propagation process of bow wave in explosive under jet impact and the relationship between critical initiation threshold and the thickness of finite-thickness explosive were analysed. The simulation results were compared and verified by the experimental data. The results show that the critical initiation threshold of TNT with a thickness of 43 mm is 37 mm3·μs-2, and the expansion rate of reaction products varies by at least one order of magnitude between different responses. When the jet impacts on a finite-thickness explosive, a certain distance is required for a bow shock wave evolving into a detonation wave. The higher the tip velocity of the residual jet is, the shorter the distance is required for the evolution of bow shock wave to detonation wave. Therefore, the decrease of explosive thickness will lead to the increase of critical initiation threshold of finite-thickness explosive, and the logarithm of critical initiation threshold is approximately linear with the logarithm of explosive thickness.

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    • LI Shu-rui, DUAN Zhuo-ping, GAO Tian-yu, OU Zhuo-cheng, HUANG Feng-lei

      Online:November 26, 2020  DOI: 10.11943/CJEM2020238

      Abstract:To investigate the shock initiation characteristics of the insensitive aluminized melt-cast explosives, a one-dimensional Lagrangian test system was established with the manganin piezoresistive pressure gauges and the loading technique of chemical explosion. The shock initiation process of an aluminized DNAN-based melt-cast explosive was measured, and the growth histories of pressure were obtained under different loading pressures. By virtue of the mesoscopic model of reaction rate of the aluminized melt-cast Duan-Zhang-Kim (DZK) , the parameters of the aluminized explosive were determined and then the shock initiation process was simulated numerically. It is found that the higher the loading pressure is, the faster the detonation grows inside the aluminized explosive. In the shock initiation of the aluminized melt-cast explosive, the reaction degree and reaction rate are low near the leading wave front. However, the reaction rate of explosive after wave increases continuously and reaches the peak value in a while with the ignition reaction and the accumulation of chemical reaction Furthermore, compared with the growth history of particle velocity, those of pressure involve more detail of the growth of reaction rate, which are more suitable to be used in validating the reaction rate models and determining the parameters of reaction flow models.

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    • ZHANG Qi-lin, DUAN Zhuo-ping, MENG Fan-xing, NAN Hai, WANG Xin-jie, HUANG Feng-lei

      Online:November 09, 2020  DOI: 10.11943/CJEM2020203

      Abstract:To study the stability of a cast polymer-bonded explosive (PBX) during penetration, projectiles with the PBX-1 charge was launched by a 155mm gun to penetrate concrete targets. The penetration depths at different velocities were obtained, and the critical penetration velocity for maintaining the charge stability was about 490 m·s-1. Based on the viscoelastic statistical crack (Visco-SCRAM) model, the experiments for testing penetration stability were modelled by a fluid-solid coupling method with large deformation. Thermal-mechanical responses of the charge during penetration were obtained and reasons for the unexpected ignition of the charge were analyzed. The numerical results and experimental data are in a good agreement. The results show that no obvious deformation or damage is observed for the projectile shell, while the cast PBX charge undergoes large deformation and part of charge seeps out from the end gap. During the penetration process, the charge collides with the bottom of charge chamber at high speed and forms a local high-pressure zone. The maximum pressure exceeds 500 MPa when the charge tail is impacted. The tail of the charge is deformed and damaged severely, which may lead to a highly localized temperature and even ignition.

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    • CAO Ming-jin, CHEN Li, FANG Qin

      Online:October 16, 2020  DOI: 10.11943/CJEM2020212

      Abstract:To predict the resistance to penetration of the ultrahigh molecular weight polyethylene laminate(UHMWPEL) accurately, a three-dimensional finite element simulating method of composite structures laminate based on the ABAQUS/Explicit solver platform was developed. A user-defined subroutine VUMAT was proposed to define material behavior by dividing the laminate into two parts with orthotropic lamina and cohesive interface. The lamina and cohesive interface utilized the Hashin criterion and the quadratic stress criterion as the damage initiation criterion separately, while both of them adopted the bilinear constitutive model and the damage evolution method derived from fracture toughness. The residual velocities and damage states of UHMWPEL with thickness of 10 mm and 20 mm penetrated by wedge-shaped steel fragment simulation projectile(FSP) with different initial impact velocities were simulated. The results show that, compared with the existing experiments, the prediction errors of ballistic limits of 10 mm and 20 mm UHMWPEL are 0.6% and 11.3%, respectively, and those of all residual velocities of FSP are less than 14.2%. During the damage and failure process of UHMWPEL, punching failure and local bulging occur in the first stage, followed by large-scale bulging, large-area delamination and fiber tensile failure. This two-stage characterization is similar to that observed in existing experiments, which verifies the reliability of the proposed simulating method.

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    • HUANG Bing-yu, XIONG Wei, ZHANG Xian-feng, LIU Chuang, DU Ning, TAN Meng-ting

      Online:October 23, 2020  DOI: 10.11943/CJEM2020231

      Abstract:To improve the penetration depth in the target subjected to the jet of reactive materials liner, a shaped charge with Al/Ni-Cu double-layered reactive liners based on the K-charge structure was proposed. The outer and inner liner of the double-layered reactive liner are made of oxygen-free copper and Al/lNi reactive material, respectively. Experimetal study of jet formation, static armor-piercing into steel ingots and the penetration power to typical concrete targets were carried out seperately by using X-ray cinematography. Results show that the double-layered reactive liners with K-charge can form a continuous jet after detonation with obvious pit areas in steel and concrete targets. However, the jet has no obvious reaming effect on penetrating the target. A combined damage effect of kinetic energy and chemical reaction can be achieved by the Al/Ni-Cu double-layered reactive liners. Compared with the Cu-Cu double-layered, less jet accumulated in the target penetrated by the new double-layered reactive linears. Meanwhile, the penetration depth and volume of the steel targets were increased by 20.1% and 23.0%, respectively, while the penetration depth and volume of the concrete targets were increased by 17.2% and 45.6%, respectively.

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    • Online:December 15, 2020  DOI: 10.11943/CJEM2019182

      Abstract:In order to study the influence of stoichiometric ratio and oxygen content of oxidant on detonation process of gelled gasoline/gas-phase oxidant, a three-dimensional two-phase detonation model of gelled gasoline and gas-phase oxidant was established, and the internal detonation process of pulse detonation engine was simulated numerically using conservation element and solving element method. The effect of stoichiometric ratio and oxygen content of oxidant on the formation time, formation distance, peak pressure and propagation velocity of detonation wave were analyzed. The numerical results indicated that when the stoichiometric ratio is lower than 1.15, the formation distance and time of detonation wave decrease with increasing of stoichiometric ratio, and the pressure peak and propagation velocity of detonation wave increase at the same time. When the stoichiometric ratio is of 1.15, the formation distance and time of detonation wave are 0.288 m and 278 μs, and the pressure peak and propagation velocity of detonation wave are 1.85 MPa and 1437 m·s-1, respectively. The pressure peak and propagation velocity of detonation wave increase with increasing oxygen content of oxidant, and when the oxygen content increases from 23% to 48%, the pressure peak and propagation velocity of detonation wave increase from 1.85MPa, 1437 m·s-1 to 2.85MPa, 1868 m·s-1, respectively.

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    • Online:November 06, 2020  DOI: 10.11943/CJEM2019237

      Abstract:The thermal stress fracture of polymer bonded explosive (PBX) was studied by a combined simulated and experimental method using the notched PBX cylinders. A 2D axisymmetric finite element model, which contained temperature related material properties, was employed to calculate the thermal elastic-plastic response of PBX cylinders under the condition of the initial cooling temperature of 50 ℃ and cooling rate of 10 ℃·min-1. Temperature, strain and acoustic emission (AE) measurements were used in an air-cooling test for verification. Simulation results show that there is a temperature boundary layer near the surface and a temperature difference in the cylinder, resulting in tension stress greater than the strength of the PBX. A circular notch in the cylindrical surface distinctly amplifies the thermal stress and the stress gradient. The factor of stress concentration reaches a maximum of 1.6 when the notch radius is 2 mm. the PBX endures brittle broken during thermal shock when thermal stress exceeded its tension strength, accompanied with strong AE signals and a sharply decline on strain-time response. The critical fracture temperature of cylinders with an without the notch determined by simulation are respectively 8.3 ℃ and 12.6 ℃, while the value determined by experiment are respectively 9.2 ℃ and 12.5 ℃.

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    • Online:August 12, 2020  DOI: 10.11943/CJEM2019260

      Abstract:In order to explore the influence of the complexity of crack distribution and shape on the particularity of ultrasonic propagation in curved surface components of polymer bonded explosives (PBX), and optimize the parameters of ultrasonic oblique incidence testing, a numerical model of ultrasonic nondestructive testing of curved PBX components was established, based on the finite element method and typical testing conditions. The surface P under the excitation of transient displacement was calculated and analyzed by COMSOL commercial software. The propagation law of the internal sound field of PBX component was simulated, the ultrasonic detection signals of different angles and cracks were calculated, and the influence of the incident angle and other parameters on the detection results of small angle oblique incidence of ultrasonic water immersion crack of curved PBX component was studied. The numerical simulation results show that when the angle between the beam and the crack is 8°~10°, the small angle oblique incidence ultrasonic detection method has the best detection performance for PBX internal crack defects, and is not affected by the crack depth. At the same time, the curved PBX simulation specimen was designed and manufactured, the small angle ultrasonic testing experiment system was built, and the ultrasonic testing experiments under different incident angles and crack parameters were carried out. The optimal testing angle (8°) obtained from the experiment was consistent with the simulation results (8°~10°), which verified the rationality of the numerical simulation results and the effectiveness of small angle ultrasonic testing.

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    • Online:November 11, 2020  DOI: 10.11943/CJEM2020045

      Abstract:The dynamic characteristics of unreacted solid explosive PBX-59 under ramp wave compression were studied with a magnetic driven loading experimental technique, and the dynamic response of PBX-59 under a peak pressure up to 18.5 GPa was obtained. . The p-V relationship, the acoustic velocity-particle velocity relationship and other dynamic parameters of PBX-59 were obtained by the iterative Lagrange data processing method modified by impedance matching under the ramp wave compression. Combined with the dyamic parameters and isentropic equation of state derived from experimental data, the experimental results were hydrodynamically simulated. The numerical calculation agree well with the experimental results, which verifies the validity of the experimental technology, data processing method, and physical model.

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    • Online:November 10, 2020  DOI: 10.11943/CJEM2020062

      Abstract:To characterize the structure of TATB-based polymer bonded explosives(PBX) on the meso-scale, an automatic granule boundary extraction method based on the two-dimensional(2D) reconstructed CT images with low quality is presented. Binarization was first performed according to the gray level distribution of the original CT images of TATB-based PBX. Then a proposed elastic capsule algorithm was applied to the binary images and an approximate location of the granule boundary was obtained. With a combination of morphological operations and the marker-based watershed algorithm, a more accurate segmentation of TATB-based PBX granules was realized. The present granule boundary extraction method for 2D CT images of TATB-based PBX shows improved accuracy and portability, as compared to Canny algorithm, iterative phase congruency, SLIC superpixels and other feature extraction techniques.

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    • Online:September 27, 2020  DOI: 10.11943/CJEM2020113

      Abstract:Six kinds of preparation methods of physical mixing methods, ball milling methods, vapor deposition methods, electrostatic spray/spinning approaches, solvent/non-solvent methods and 3D printing methods are summarized. Research progress of Al-fluoropolymer reactive materials in recent years are reviewed from the aspect of product performance and method advantages and disadvantages. The reaction process of aluminum-fluoropolymer reactive materials at slow heating rate and fast heating rate are introduced. The promising research directions in the future are pointed out, including design a new method that combines the advantages of various preparation methods and more attention should be paid to strengthen the research on the reaction mechanism of aluminum-fluoropolymer reactive materials when heated.

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    • Online:November 18, 2020  DOI: 10.11943/CJEM2020160

      Abstract:In order to understand the reaction characteristics of azide binder/non-isocyanate bonding system, curing processes of 3,3-bis(azidomethyl)oxetane-tetrahydrofuran copolymer(PBT)/bis-propargyl-succinate(BPS) binding system were investigated by microcalorimetry. The kinetic parameters and characteristic temperatures of PBT/BPS binding system were calculated through Kissinger method and Crane method. The equation between the complete curing time and the curing temperature was also fitted, demonstrating that the apparent activation energy, pre-exponential factor, reaction order and heat for curing reaction of PBT/BPS bonding system are 81.94 kJ·mol-1, 108.48 s-1, 0.93 and -926.88 J·g-1, respectively. The values of gelation temperature, curing temperature and post-curing temperature were examined to 319.29 K, 344.52 K and 366.11 K, respectively. Besides, self-catalyzed phenomenon could be witnessed to exist in the curing reaction process of the PBT/BPS bonding system. The equation between the complete curing time and the curing temperature was y=8.3345×104e-0.02309x-11.116.

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    • Online:September 29, 2020  DOI: 10.11943/CJEM2020185

      Abstract:In order to speed up the development of new energetic materials and reduce the time and resource consumption caused by a large number of experiments, a method for predicting enthalpy of formation of energetic materials is proposed based on the theory of material genetic engineering. Firstly, the collected atomic coordinate data representing the molecular structure of energetic materials were converted into a coulomb matrix representing the cartesian coordinate system in the molecule to eliminate the influence of translation, rotation, index order and other operations on the prediction of enthalpy of formation. Then, the enthalpy of formation of energetic materials was predicted according to the proposed fusion model of Convolutional Neural Network (CNN) and Bi-directional Short-term Memory Network (Bi-LSTM) based on Attention mechanism. In this way, not only can the characteristics of the data be extracted effectively, but also the correlation between the data and the lack of long-term dependence can be fully considered. Meanwhile, the influence of important characteristics on the prediction results can be highlighted. The comparison of experimental results shows that the proposed method based on deep learning has the lowest experimental error in the prediction of enthalpy of formation. Its Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), Root Mean Square Error (RMSE) and Root Mean Squared Logarithmic Error (RMSLE) are 0.0374, 1.32%, 0.0541 and 0.028, respectively. The prediction goal of "structure-performance" is realized, and a new method is provided for the prediction of enthalpy of formation of energetic materials.

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    • Online:November 16, 2020  DOI: 10.11943/CJEM2020191

      Abstract:As the diffusion and migration of the deterrents affect the service life of gun propellants during the storage period, the molecular dynamics simulation (MD simulation) was applied to compare the diffusion rate of the small molecule dibutyl phthalate (DBP) and polyneopentyl glycol adipate (NA) in gun propellants. Meanwhile, the effect of nitroglycerin (NG) content on the diffusion of DBP and NA in double base gun propellants was explored and the diffusion mechanism was analyzed. The results indicate that the diffusivity of DBP and NA in nitrocellulose (NC) is equivalent at 5 ℃ and the diffusion coefficients are both in the order of 10-12 m2?s-11. The diffusion coefficients of DBP and NA are 1.88×10-11 m2?s-1 and 7.57×10-12 m2?s-1 at 65 ℃, respectively. The diffusion coefficients of DBP and NA are 3.42×10-11 m2?s-1 and 1.11×10-11 m2?s-1 at 85 ℃, respectively. At the same temperature, the order of the diffusion coefficient of the deterrents is DBP>NA, which shows that NA has better anti-migration properties, which are more prominent at high temperatures. Owing to the high temperature, the peak value reduces, thus weakening interaction between DBP, NA and NC, meanwhile, the fractional free volume of system increases, which is conducive to the diffusion of DBP and NA. The diffusion capacity of DBP and NA increases with the increase of NG content. Adding NG weakens the interaction between DBP, NA and NC, so DBP and NA move more actively and the diffusion ability increases. The molecular dynamics simulation method is used to study the diffusion properties of the deterrents in gun propellants, which provides important theoretical guidance for predicting the life of gun propellants.

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    • Online:November 12, 2020  DOI: 10.11943/CJEM2020192

      Abstract:3,4‐Bis(3'‐aminofurazan‐4'‐yl)furazan(BATF)was synthesized by reduction with stannous chloride in glycerol using 3,4‐bis(3'‐aminofurazan‐4'‐yl)furoxan(BAFF) as raw material. 3,4‐Bis(3'‐nitrofurazan‐4'‐yl)furazan(BNTF) was prepared from BAFF by using hydrogen peroxide as oxidantwith total yield of 59.0%. The structures of BATF and BNTF were characterized by 1H NMR,13C NMR,IR,MS spectra and elemental analysis,and the single crystal structure data of BNTF was obtained successfully. The crystal belongs to orthorhombic system,space group P212121 with crystal parameters a=0.71437(10) nm, b=0.96839(11)nm,c=51555(17)nm,V=1.0484(2)nm3,Z=4,Dc=1.876 g·cm-3,F(000)=592. The influence of molar ratio,reaction time,and reaction temperature on the yield of BNTF was investigated. Results show that the optimum conditions are as follows:n(BATF)∶n(35% H2O2)∶n(98% H2SO4 )∶n(Na2WO4?2H2O)=1∶60∶40∶0.86,the reaction time is 3 h,the reaction temperature is 30 ℃ and the yield of BNTF is 93.3%. The thermal stability of BNTF was determined by DSC and TG‐DTG methods. Apparent activation energy Ea(147.83 kJ·mol-1),pre‐exponential factor A(9.33×1015 min-1)and decomposition rate constant k (2.18×10-44)of thermal decomposition reaction for BNTF were calculated by Kissinger method,Rogers method and Arrenhis method,respectively. The detonation velocity(8.3 km·s-1)and detonation pressure(31.3 GPa)of BNTF were estimated by Ka‐mlet‐Jacobs equation. Characteristic drop height of impact sensitivity(H50=43.0 cm)and friction sensitivity(36.0%)for BNTF were measured according to GJB772A-1997 methods 601.2 and 602.1,respectively.

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    • Online:December 02, 2020  DOI: 10.11943/CJEM2020214

      Abstract:In order to develop a scale-up and continuous preparation method, the microchannel crystallization technology based on solvent/non-solvent method has been used to prepare hexanitrohexaazaisowurtzitane/octogen (CL-20/HMX) co-crystal. The field emission scanning electron microanalyzer (FE-SEM), X-ray powder diffraction (XRD), Raman spectroscopy, Fourier infrared spectroscopy (FT-IR), thermal analysis and sensitivity test were applied to characterize and analyze the morphology, structure, thermal performance and sensitivity of samples. Results show that this method has successfully prepared CL-20/HMX co-crystal. Its apparent morphology is the flower clusters with a diameter of 20-30 μm, assembled by platelet crystals with thickness of 200-600 nm, accompanying individual flaky crystals (thickness of 200-600 nm). The CL-20/HMX co-crystal prepared by microchannal crystallization has only one sharp exothermic decomposition peak during the exothermic process. Its exothermic peak temperature is at 243.4 ℃, which is lower than that of the raw materials CL-20 (250.2 ℃) and HMX (284.7 ℃). Its temperature range of thermal decomposition is only from 242.7 to 246.0 ℃, much narrower than those of raw CL-20 (230.0-254.6 ℃) and HMX (281.0-290.7 ℃), which means a higher energy release efficiency. Its apparent active energy is 470.75 kJ·mol-1,falling between CL-20 (175.04 kJ·mol-1) and HMX (481.45 kJ·mol-1), which is 297.29 kJ·mol-1 hagher than that of raw CL-20,indicating a good thermal stability. Its impact sensitivity is 18 J, which is 8 J and 3.6 J higher than those of raw CL-20 (10 J) and HMX (14.4 J) respectively, and the friction sensitivity is 20% lower than that of raw CL-20. The sensitivity results show the safety of the CL-20/HMX co-crystal has been improved compared with the raw materials.

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    • Online:January 11, 2021  DOI: 10.11943/CJEM2020332

      Abstract:

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    Vol, 28, No.12, 2020    

      >Energetic Express
    • Zhao Xu

      2020,28(12):1131-1131, DOI:

      Abstract:

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    • >Preparation and Property
    • WANG Zhi-qiang, HUANG Yin-sheng, LI Rui, MAO Li

      2020,28(12):1132-1139, DOI: 10.11943/CJEM2020105

      Abstract:In order to explore the possibility of substituting nanothermite-explosive hybrid composites for primary explosive, nano-Al, nano-Bi2O3, raw HNIW and nano-HNIW were used to prepare Al/Bi2O3-HNIW by two methods: solvent-nonsolvent method (SN) and physical mixing method (PM). The properties of Al/Bi2O3-HNIW were characterized and tested by scanning electron microscope (SEM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), closed bomb test and lead plate test. Results show that Al/Bi2O3 is uniformly coated on the surface of HNIW by SN. The optimal mass ratio of Al/Bi2O3 to HNIW for Al/Bi2O3-HNIW (SN) is 3∶7, with a high pressurization rate of 2.914 GPa·s-1, which is triple of Al/Bi2O3-HNIW (PM),and the pressurization time is shorter. The electrostatic sensitivity of Al/Bi2O3-HNIW (SN) is significantly lower than lead styphnate and lead azide, and even PETN. Al/Bi2O3-HNIW(SN) can detonate RDX using PETN as intermediate charge. Al/Bi2O3-HNIW (SN) is expected to be used as a substitute for primary explosive for its excellent safety and initiation performance.

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    • ZHANG Li, BAI Liang-fei, LI Hao, HUANG Jia-wei, SHEN Hong-yang, XIA Yuan-hua, YANG Hai-jun

      2020,28(12):1140-1146, DOI: 10.11943/CJEM2020126

      Abstract:Deuterated nitroguanidine (NQ-d4) and deuterated 1,1-diamino-2,2-dinitroethylene (FOX-7-d4) were synthesized via H/D exchange starting from nitroguanidine (NQ) and 1,1-diamino-2,2-dinitroethylene (FOX-7). The target products were characterized by IR, NMR (1H and 13C), HPLC, TG-DTG, DSC and neutron diffraction. DSC/TG data show that the decomposition temperatures of NQ-d4 and FOX-7-d4 were 2.5 ℃ and 2.6 ℃ higher than those of NQ and FOX-7, respectively. The deuteration rates of NQ-d4 and FOX-7-d4 are respectively 95.27% and 98.87% as measured by neutron diffraction. The purities of NQ-d4 and FOX-7-d4 are respectively 99.51% and 99.28% obtained by HPLC via area normalization method.

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    • GUO Rong, DUAN Xiao-hui, LI Hong-zhen, WU Bo

      2020,28(12):1147-1155, DOI: 10.11943/CJEM2020079

      Abstract:Phonon spectra play an important role in studying the thermodynamic properties of solids and the microscopic process of initiating chemical decomposition reactions, which can help to reveal the microscopic physical mechanism of initial thermal decomposition mechanism, detonation performance and sensitivity. In this work, the density functional theory with dispersion correction was used to calculate the phonon spectra and thermodynamic properties of 2,4,6,8,10,12-hexanitrohexaazaiso-wurtzitane(CL-20)/1,4-dinitroimidazole(1,4-DNI) cocrystal and co-formers. Through analyzing the phonon density of states, the way in which the phonon mode stores and transfers energy was determined, the direction of thermal energy flow was proposed, and the trigger bond and impact sensitivity order were predicted. The results show that the initial bonds of ε-CL-20 and CL-20/1,4-DNI cocrystal are predicted to be N─NO2 bonds on CL-20 molecules; the initial thermal decomposition of 1,4-DNI may be related to the ring-opening of imidazole. By comparing the phonon density of states of CL-20 and 1,4-DNI molecules in cocrystal and its pure components. It can be found that the thermal stability of both CL-20 and 1,4-DNI molecules were improved in cocrystal, so that the thermal stability of the cocrystal being superior to the co-formers. According to the "doorway" mode phonon number and characteristic vibration frequency Δωd, the order of the impact sensitivity is predicted of to be ε-CL-20>CL-20/1,4-DNI>1,4-DNI, completely consistent with the experimental measurement results. The thermodynamic parameters of CL-20/1,4-DNI cocrystal and co-formers have been calculated by phonon spectra, at the same temperature, the order is CL-20/1,4-DNI>ε-CL-20>1,4-DNI. In addition, low-frequency phonons contribute the most to heat capacity(CV), and the chemical bond breakage caused by energy transfer may undergo a multi-phonon up-pumping process.

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    • CHEN Ling, ZHAO Yin-bin, PANG Xiao-qing, ZHANG Yong

      2020,28(12):1156-1162, DOI: 10.11943/CJEM2020137

      Abstract:A rapid and accurate high performance liquid chromatographic method was developed for the simultaneous determination of TATB and HMX in explosive formulations. Dimethyl sulfoxide (DMSO) was used as the solvent and ultrasonic assisted to dissolve the sample. The influences of sample weight, dissolve time, mobile phase type, chromatographic column type and detection wavelength on results were investigated. The results show that HMX and TATB were confirmed to separate within 6.5 min by using C18 chromatographic column with mobile phase of acetonitrile and water at 45/55(V/V). And the HMX and TATB could be extracted completely at the condition of ultrasonic for 1.0 h and standing at room temperature for more than 4.0 h after they were dissolved in 250 mL DMSO. The relative standard deviation of reproducibility (n=8) was 0.55% and 0.99%, respectively. Linear relationships between values of peak area and mass concentration of TATB and HMX were good in the ranges of 0.032-0.056 mg·mL-1R2=1.0000) and 0.011-0.016 mg·mL-1R2=0.9999).

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    • >Propulsion and Projection
    • ZHOU Cheng, LI Ji-zhen, LI Xiang-zhi, Qu Bei, CHANG Pei, WANG Bo-zhou, LIU Ning

      2020,28(12):1163-1169, DOI: 10.11943/CJEM2020069

      Abstract:The single crystal of hydrazinium 3,5-dinitroamino-1,2,4-triazole (HDNAT) was cultivated by slow evaporation from solvent of methanol/water, and its crystal structure was determined by X-ray singal-crystal diffractometer. The crystal structure analysis indicates that HDNAT belongs to monoclinic system with space group P2(1), and the crystal parameters are a = 0.35976(12) nm,b = 0.9348(3) nm,c = 1.1833(4) nm,V = 0.393.9(2) nm3Z = 2,Dc = 1.91 g·cm-3μ = 0.170 mm-1F(000)=230. The thermal behavior of HDNAT was studied by TG-DTG. The decomposition peak of HDNAT is 193.17℃ (DSC), and it decomposes at solid state. The composite modified double-base (CMDB) propellant formulation based on HDNAT was designed and prepared, and its energy characteristics such as explosion, specific volume, density, characteristic velocity, and specific impulse and combustion performances were tested. For HDNAT-based CMDB propellant formulation, the tested explosion is 6042 kJ·kg-1, specific volume is 638 L·kg-1, density is 1.767 g·cm-3, characteristic velocity is 1592.3 m·s-1. The study of combustion performances of Φ50 mm engine show that it has stable performances at pressure of 15 MPa, the specific impulse is 250.91 s. Compared with RDX-CMDB propellant, the burning rate of HDNAT-based CMDB propellant increases by 18.8%, and the pressure exponent in partial pressure range is above 0.4.

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    • REN Xiao-ting, LI Gang, WANG Ye-teng, DING Ning, HE Jin-xuan

      2020,28(12):1170-1177, DOI: 10.11943/CJEM2020130

      Abstract:Triaminoguanidinium nitrate (TAGN) was obtained via amination of guanidinium nitrate, and its structure and properties were characterized by elemental analysis, fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and scanning electron microscope (SEM). Short block-like TAGN crystal particles were prepared by ultrasound assissted cooling crystallization in water. The influencing factors of crystal modifier, ultrasonic and cooling process for controlling crystal morphology and particle size, were analyzed by SEM and particle size analysis, and results revealed that ultrasound assissted process can lead to uniform crystalline morphology with narrow particle size distribution. The crystal morphology modifier and temperature control program have a significant effect on the particle size, particle size distribution and crystalline morphology of TAGN. Under the action of ultrasonic (750 W, 20 KHz), two kinds of high-quality TAGN crystals with uniform crystalline morphology, smooth surface without sharp edge angle, high density and narrow particle size distribution were prepared by using suitable cooling process and PVP K30 (0.03%) as the crystal morphology modifier. Compared with present manufactured raw materials,the comprehensive performance of TAGN have been improved, the characteristic explosion percentage of two kinds of TAGN decreases from 20% to 8% and 4% apart, the characteristic drop height increases 5.9 cm and 3.4 cm apart, the density increases from 1.571 g·cm-3 to 1.586 g·cm-3 and 1.589 g·cm-3 apart, the onset melt point increases from 224.8 ℃ to 227.7 ℃ and 228.2 ℃, respectively. Charging with the prepared product will significantly improve the charging process performance and solid content, so as to improve weapon performance.

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    • SUN Chu-yan, SU Hang, ZHANG Qi

      2020,28(12):1178-1183, DOI: 10.11943/CJEM2019315

      Abstract:The minimum ignition temperature is an important basis to determine whether the fuel air explosive has the phenomenon of fire channeling. The mixture of flammable liquid and air forms gas-liquid two-phase cloud. At present, the research on the minimum ignition temperature and the specific influence of cloud concentration, particle size and velocity on the minimum ignition temperature are still in a blank stage. In this paper, the research method of dust minimum ignition temperature is used for reference. With Godbert- Greenwald (G-G) heating furnace as the main test instrument, the minimum ignition temperature test system of gas-liquid two-phase cloud is established. On this basis, the cloud instantaneous concentration particle size test device is established. With ethanol as the experimental reagent, the particle size distribution of ethanol gas-liquid two-phase cloud was measured under the experimental conditions of 7000 g·m-³ cloud concentration at the center of the heating furnace and 0.06-0.10 MPa fuel dispersion pressure. The effects of particle size distribution and cloud velocity on the minimum ignition temperature were analyzed and discussed. Under the concentration of 7000 g·m-³, with the increase of pressure from 0.06 MPa to 0.10 MPa, the particle size decreased from 146.58 μm to 70.97 μm, the lowest ignition temperature of ethanol first decreased from 468 ℃ to 464 ℃, then increased to 476 ℃, and finally kept at 475 ℃. When the pressure is less than 0.07 MPa, the main factor affecting the MIT is the particle size, which decreases with the drop diameter. When the pressure is greater than 0.07 MPa, the main factor affecting the MIT is the flowing velocity. Since the velocity is constant, the minimum ignition temperature also stays stable.

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    • ZHANG Lei, SHE Hu-qing

      2020,28(12):1184-1189, DOI: 10.11943/CJEM2020118

      Abstract:In order to investigate the gas jet flow field and thrust characteristics of solid rocket engine working underwater, an experimental study on the underwater work of rocket engine was carried out on the lifting platform connected to the hull. The expansion process of nozzle gas jet in open water was observed by high speed camera system, and the evolution process of underwater gas jet was obtained. The combustion chamber pressure and thrust of underwater rocket engine were measured. The thrust characteristics of the rocket engine under the water depth of 10 m, 30 m and 50 m were compared and analyzed. The experimental results show that when the engine is ignited underwater, the shape of gas jet is changed because of the interaction between water environment and gas, and gas liquid turbulent mixing is intense. With the increase of water depth, the combustor pressure is basically unchanged, the working thrust of the engine decreases. The relationship between thrust and water depth is nonlinear. Under the same water depth condition, the smaller the engine throat diameter, the smaller the thrust reduction, and the smaller the combustion chamber pressure, the smaller the thrust reduction.

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    • >Reviews
    • HE Zhi-cheng, XIA Zhi-xun, HU Jian-xin, MA Li-kun

      2020,28(12):1190-1199, DOI: 10.11943/CJEM2020103

      Abstract:Electrically controlled solid propellants (ECSPs) have the characteristics of on-line combustion, power-off extinction and real-time adjustable burning rate, which has good application prospects in the field of propulsion from the micro-scale to macro-scale solid rocket motors. In this paper, the preparation methods of ECSPs worldwide in recent years are summarized, which are mainly swelling method, melt mixing method, room temperature method, freeze-thaw method and 3D printing method. The thermal stability, electric resistance characteristics, ignition and combustion performance, aging features, arc ablation and plume characteristics of ECSPs are reviewed. The hydroxylamine nitrate-based ECSPs with low toxicity, high specific impulse and high controllability and perchlorate-based ECSPs with high flameout pressure threshold are the current research focuses. The future research directions of ECSPs is to strengthen and improve the properties research of ECSPs, develop and normalize the ignition and combustion performance test devices and method, improve the burning rates of ECSPs, study the ignition and combustion mechanism of ECSPs deeply, and establish the ignition and combustion models.

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    • BAO Li-rong, WANG Hui, CHEN Yong-yi, ZHANG Wei, ZHANG Xiao-jun, HUANG Yin-sheng, SHEN Rui-qi, YE Ying-hua

      2020,28(12):1200-1210, DOI: 10.11943/CJEM2020100

      Abstract:Hydroxylammonium nitrate (HAN)-based propellant has the advantages of high energy, insensitive and non-toxic combustion products. It offers advantages in the continuous start-up and thrust adjustment of propulsion system. The formula composition, decomposition characteristics, ignition and combustion performance of HAN-based liquid propellant, HAN-based gel propellant and HAN-based solid propellant were reviewed. The key points for future research were proposed: preparing high-performance catalyst bed for HAN-based liquid propellants, developing electric ignition as a reliable ignition mode; improving the ignition performance of HAN-based gel propellant, accelerating the engineering applications; exploring the combustion and flameout controllable mechanism of HAN-based solid propellant, and breaking through the bottleneck of large-scale application of the propulsion system.

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    • ZENG Gui-yu, QI Xiu-fang, LIU Xiao-bo

      2020,28(12):1211-1220, DOI: 10.11943/CJEM2019241

      Abstract:The disruptive innovating technology has developed rapidly and become a significant power of promoting science & technology development and military change. In order to realize its impact on the energetic materials studies, the concept and role of disruptive technology is introduced, and several rapid growing disruptive technologies are discussed, including ultra-high energy technology, nanometer technology, additional manufacturing technology and materials genome technology. Results show that the focus on the future disruptive technologies lies on the preparation and application of metallic hydrogen, design and 3D printing of energetic ink, establishment of energetic materials genome database and fusion of its three elements, which is new opportunities and challenges for energetic materials innovation development.

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    • >Reader · Author · Editor