bluuebunny/crossref_metadata_2025_split huggingface dataset:
Constant-volume combustion performance of mixed charge of foamed propellant with nitramine propellant
Authors: Yang W T , Hu R , Zhao Y H , Xiao X , Yang J X 
Published: July 2020

Abstract
Foamed propellants based on polymer bonded nitramine explosives show high burning rates due to their porous structure and showed great potential for combustible cartridge case. Thus, the in-depth study of the co-combustion behavior of the foamed propellant and matching propellant is necessary. In this paper, closed bomb tests were used to study the co-combustion performance of nitramine propellant (RGD7) and surface coated nitramine propellant (SC-RGD7) mixed with foamed propellant. The influence of foamed propellant’s proportion in mixed charges on the combustion behavior was studied and analysed. It was found that the maximum dynamic vivacity and the value of B at maximum dynamic vivacity of mixed charge increased with the increase of added foamed propellant, resulting in better combustion progressivity. Meanwhile, the ignition delay of foamed propellant influenced the first stage of combustion, and the penetration combustion of foamed propellant influence the middle stage.
Effect of gap on the polymorphic transition of ε-CL-20
Authors: Wu Z K , Song X D , Zheng W , Pei J F , Zhang Ch , Zhang R , Zhao F Q 
Published: July 2020

Abstract
The ε-form 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.05,9.03,11] dodecane (CL-20) is the highest energy density compound which can be applied in practice at present. In this work, the effect of GAP on the polymorphic transition of ε-CL-20 was investigated by Raman spectroscopy and Calvet microcalorimeter method. The results show that the polymorphic transition temperature of ε-CL-20 to α-CL-20 can be reduced significantly by GAP, and the accurate temperature is 83.7°C. This investigation provides guidance to process condition selection for GAP-based propellants containing CL-20.
Copper azide nanowires@rgo energetic composite with low electrostatic sensitivity
Authors: Liu X W , Li T T , Hu Y , Ye Y H , Shen R Q 
Published: July 2020

Abstract
A novel energetic composite with low electrostatic sensitivity was successfully synthesised in this work. Copper nanowires decorated reduced graphene oxide (CuNW@rGO) precursor was prepared through a facile one-pot hydrothermal approach. Then the precursor was deposited on silicon substrate by electrophoretic deposition, which greatly reduced the security risks of directly handling of powder sample. Copper azide nanowires(CANW)@rGO was in-situ fabricated by reaction of copper nanowire (CuNW ) @rGO with HN3 gas. The materias were characterized by SEM-EDS, TEM, XRD, DSC and Raman spectroscopy. The electrostatic sensitivity of CANW@rGO composite was investigated by electrostatic sensitivity tester JGY-50III. The discharge energy at 50%(E50%) of CANW@rGO composites with rGO contents of 15 and 25 wt% were 0.92mJ and 1.43mJ, respectively. The results indicate that the electrostatic sensitivity of the as-prepared CANW@rGO energetic composite was highly reduced with the addition of rGO.
Preparation and properties of w(Al) alloy powders
Authors: Li Shun , Tang Yu , Zhang Xiaohong , Zhao Kongxun , Bai Shuxin 
Published: July 2020

Abstract
In order to improve the density and penetrating ability of Al/Ni energetic structural materials, W with the high density and hardness generally was introduced. But the oxidation reaction of W factually is difficult to induce because of the strong binding energy. It then results in the great reduce of energy release. In this work, W(Al) super-saturated solid solution powders with the average particle size of 3.9μm, were synthesized by mechanical alloying. In this super-saturated solid solution, Al atoms are evenly distributed in the W lattice and Al content can reach 80 at.%. Moreover, Al is still stable in the lattice of W but not form Al-W intermetallic, when W(Al) powders were annealed at 1200°C for 30 min in vacuum. As a large amount of Al atoms into W, the activity of W is greatly improved, thus the combustion heat of W(Al) super-saturated solid solution powders can reach about 11.3KJ/g.
Study on the traceability of equivalent water content of nitrogen tetroxide measured by nuclear magnetic method
Authors: Shao H F , Liu Y J , Ren W J , Mao Y N , Li J , Zhao X G , Ji K J 
Published: July 2020

Abstract
This paper studies the traceability of the certified value of the reference material with the equivalent water content of nitrogen tetroxide(NTO) and green nitrogen tetroxide(MON), which lays the foundation for the certified value of the reference material. The purity of bibenzyl was measured by differential scanning calorimetry(DSC), the water content of deuterium acetonitrile(DAN) was measured by Karl Fischer method, the proton content and water content of deuterium acetonitrile(DAN) were measured by nuclear magnetic resonance spectroscopy(NMR), and the equivalent water content of deuterium acetonitrile(DAN) - nitrous oxide system was measured. All of these three methods can be directly traced to SI units, which are internationally recognized potential reference measurement methods. Therefore, the fixed value of equivalent water content reference material has metrological traceability.
Effect of storage temperature on explosion characteristics of RDX-based thermobaric explosive
Authors: Xiao W , Chen K , Xing H D , Wang B L 
Published: July 2020

Abstract
The effect of storage temperature on explosion characteristics of the free space explosion of RDX-based thermobaric explosives was studied, and the fireball and the overpressure were obtained. The results showed that the temperature and the volume of the fireball can reach 2400 K and 400 m3 respectively. Low temperature and temperature shock will reduce the temperature and the volume of the fireball and the overpressure. In addition, the aluminum powder does not burn completely, and the time to reach the maximum temperature will be delayed by at least 33 ms. The high temperature can slightly enhance the thermal effect and the pressure effect.
Thermal behavior and non-isothermal decomposition reaction kinetics of catalyzed hniw-cmdb propellant
Authors: Xu S Y , Zhao F Q , Yao E G , Jiang H Y , Yi J H , Li M , Pei Q , Hao H X 
Published: July 2020

Abstract
The thermal behavior under pressure of 0.1, 4, and 7 MPa and non-isothermal decomposition reaction kinetics under pressure of 4 and 7 MPa of the composite modified double base propellant containing hexanitrohexaazaisowurtzitane (HNIW-CMDB propellant) was investigated by differential scanning calorimetry (DSC). The results showed that there are two exothermic peaks on DSC curve under 0.1 MPa. The exothermic peak temperature decreases with surroundings pressure increasing. There is only one exothermic peak on every high pressure DSC curve. The exothermic peak temperature under every pressure increases with heating rate increasing. The exothermic decomposition kinetic parameters of the propellant changed while the reaction mechanism function didn’t change when catalyzer was added into propellant or testing surroundings changed. The kinetic equation of exothermic decomposition reaction mechanism under 4 MPa and 7 MPa are Avrami-Erofeev (n=2/3).
Design and performance of NiCr-based micro-heater with lower excitation energy
Authors: Liu W , Su Q , Xue Y , Xie R Zh , Ren X M , Liu L 
Published: July 2020

Abstract
Low energy and miniaturization are two main development directions for the MEMS (Micro-Electro-Mechanical System)-based initiator. The MEMS-based initiators or called fire components were fabricated by the way of that the secondary explosive charges were coated or synthetized with in-situ method onto the NiCr-based micro-heater surface. The firing voltage experiments of the fire component under capacity loading were performed. The fire voltages of the fire components with rectangle micro-heater increase linearly with the increasing of micro-heater’s width, and decrease with the increasing of micro-heater’s thickness. The fire voltages of the fire components with Pyrex7740 substrate cut down to 50%, compared to the fire component with silicon substrate. The fire component with lower explosive density contributes to reduce the fire voltage. The micro-heater with parallel connection structure or called parallel micro-heaters cannot have lower fire voltage than the single micro-heater, but have more reliability to initiate the secondary explosive.
Assessment of second-order Møller-Plesset perturbation theory for isomerization and dissociation energies of nitramide
Authors: Yu T , Liu Y Zh , Lai W P , Ma Y D , Ge Zh X 
Published: July 2020

Abstract
Based on the optimized molecular geometries at the B3LYP/cc-pVDZ level, the electronic and nuclear repulsion energies of nitramide (NH2NO2), O-nitrosohydroxylamine (NH2ONO), 1-hydroxydiazene 1-oxide (NH=N(O)OH), the transition state between NH2NO2 and NH2ONO, the transition state between NH2NO2 and NH=N(O)OH, NH2 radical, NO2 radical, H2O, N2O, H2, N2, O2, H, N and O were calculated by various second-order Møller–Plesset perturbation theory (MP2) methods. The domain based local pair natural orbital (DLPNO), explicitly correlated F12, density fitting (RI), spin-component scaled (SCS) and orbital optimized (OO) calculations were employed in MP2 calculations. The isomerization and dissociation energies of NH2NO2 were estimated by CCSD(T)-F12-RI as benchmark method. The testing results indicate that the deviations can be reduced by SCS method efficiently.
Quasi-static mechanical behaviors of different inert particle reinforced Al/PTFE reactive composites
Authors: Yuan Ying , Liu Zhenyang , Geng Baoqun , Wang Haifu 
Published: July 2020

Abstract
In this paper, the quasi-static mechanical behaviors of particle reinforced aluminum/polytetrafluoroethylene (Al/PTFE) reactive composites are studied. The mechanical behaviors of composites with the volume fraction of 30% W, WC, SiC and SiO2 respectively are compared by the quasi-static compression test, and the failure mechanism is analyzed. Test results show that SiC/SiO2 particle reinforced composites show better toughness, while W/WC particle reinforced composites show more brittleness. The failure mechanism analysis indicates that the failure of particle reinforced composites is mainly caused by matrix fracture and particle spalling from the matrix.
Study of the uniformity of mixing components of energy-saturated heterogeneous composite material
Authors: Kryvanos AK , Ilyushchanka APh , Piatsiushyk YY 
Published: July 2020

Abstract
The features of mixing the components of an energy-saturated heterogeneous composite material (EHCM) were considered. The conditions for the uniform distribution of the components of the solid phase over the entire volume of the composite material were estimated and the possibility of obtaining their most dense packing was analyzed. Appropriate proportions of the particle sizes of the fine and coarse fractions of the components of the solid phase were determined, as well as their proportion. The amount of liquid phase necessary to wet the surface of the particles of the solid phase, as well as to fill the voids between them, is determined. According to the results of the calculations, the criteria were chosen for evaluating the quality of mixing EHCM components.
The calculation results are compared with observed data obtained experimentally. An appropriate technique was developed to evaluate experimental samples. The results of comparing the calculated and experimental data make it possible to build the correlation dependences of the technological characteristics of the mixing of EHCM components.
Thermodynamics and performance of Al/CuO nanothermites with different storage time
Authors: Wang Ch A , Xu J B , Shen Y , Wang Y T , Yang T L , Zhang Z H , Li F W , Shen R Q , Ye Y H 
Published: July 2020

Abstract
The storage stability of energetic materials is important for their application. In our previous work, Al/CuO nanothermites was applied to a MEMS-based solid propellant micro thruster (SPM) array because of its short ignition delay and high reaction rate.
In the current work, the storage stability of Al/CuO nanothermites, which were prepared by electrospray method and stored with different storage time, was systematically researched. The activation energy of Al/CuO nanothermites were measured by DSC. The ignition temperature and the curve pressure history of Al/CuO nanothermites were measured using T-jump and constant-volume pressurization tests, respectively. Further, the nanothermites were characterized by XRD, XPS, SEM and TEM.
The results show that the morphology and mixture uniformity of the nanothermites after a long-time storage did not change significantly. The slow decomposition of NC and the thickening of oxide layer of Al NPs existed in the storage of Al/CuO nanothermites, analysed by XPS. The activation energy (Ea
) of Al/CuO nanothermites after storage for different time was determined using the method of Kissinger, as shown in Figure 1. Ea
was decreased from 272.8 kJ/mol to 154 kJ/mol after storage for 13 months. When stored for 0, 7 and 13 months, the peak pressures of Al/CuO nanothermites were 685.8 kPa, 626.3 kPa and 625.5 kPa, respectively. In addition to the ignition temperature, it was 775 °C, 739 °C and 754 °C, respectively. This result indicated that the ignition and combustion properties of Al/CuO nanothermites are obviously reduced when stored for a long time, at room temperature.
The full version of this extended abstract will appear in Defence Technology in 2020.
Equivalent design of stiffened panel bvased on load characteristics
Authors: Li J C , Huang F L , Lu Y G , Yu C X , Chen H 
Published: July 2020

Abstract
In order to use a cheaper and homogeneous steel plate to replace the real stiffened panel in warhead tests, we numerically simulated and analyzed the deformation and failure characteristics of the stiffened panel as well as the force characteristics of the projectile in the warhead-target interaction. Based on the energy equivalence method, we first used the acceleration curve of the warhead in actual target penetration process as the reference for equivalent design and replaced it using a three-layered homogeneous steel plate. To visually assess their equivalence, we introduced Pearson correlation coefficient in statistical analysis to reflect their correlation. The results showed that the equivalent design method based on load characteristics make both consistent not only in the kinetic energy loss but also in the warhead’s target-piercing acceleration process, thus realizing the equivalence from process to final state.
Effect of inner liner material on penetration behavior of reactive material double-layered liner shaped charge
Authors: Guo H G , He S , Ma H B , Sun T , Zheng Y F 
Published: July 2020

Abstract
To improve the insufficient penetration depth of the traditional single reactive liner shaped charge, the penetration enhancement behaviors of a reactive material double-layered liner (RM-DLL) shaped charge are investigated. This RM-DLL consists of an inner liner with metal materials and an outer liner with (polytetrafluoroethylene) PTFE/Al reactive materials. Based on the platform of AUTODYN-2D code, the influence of inner liner material on the jet formation of RM-DLL shaped charge and its penetration performance of multi-layered space plates were conducted. The numerical results indicated that, during the jet formation stage, the inner metal liner mainly formed a high-velocity precursor jet and the outer reactive liner became a major part of the slug. With increasing the material density of inner liner, the jet tip velocity and tip diamater decreased, and the effective mass of precursor jet also dropped off. For a given penetration time, with the increase in the material density of inner liner, the penetration capability of the RM-DLL shaped charge increased, whereas the mass of reactive materials entering the penetrated steel target decreased significantly. This RM-DLL shaped charge, incorporating the penetration capability of a precursor metal jet and the deflagration effects of the follow-thru reactive materials, will produce extremely damage to the desired target, typically such as the armored fighting vehicles.
Study on the influencing factors of underwater unexploded ordnance destruction based on shaped charged jet
Authors: Wu J Y , Zhong M Sh , Liu Y , Xie X B , Ji Ch 
Published: July 2020

Abstract
In order to study the influence of the stand-off distance and the waterproofness on the penetration effect of liner shaped charge (LSC) jet to destroy underwater unexploded ordnance, the LS-DYNA finite element program was applied to simulate the process of the metal jet formation and penetration into steel plate under different stand-off distances and waterproof condition. On the basis, the model experiment was carried out. And combing the experimental and numerical result, it can be found that, if no waterproof measures is adopted the metal jet will directly get contact with the water, the unexploded ordnance will not be successfully destructed, moreover, with the increase of the stand-off distance, the shaped charge jet works more ineffectively.
Bandgap calculation of shock-resistant metamaterials and evaluation of shockwave resistance
Authors: Li X R , Wang Zh G , Wang G H , Ma Y W 
Published: July 2020

Abstract
Theoretical bandgap calculation and numerical simulations were carried out in order to evaluate the shockwave resistance of the structures made of metamaterials, specifically in real applications. Assuming that the microstructures of the shockwave-resistant metamaterials are the same as that of the phononic crystals, a bandgap calculation model was constructed based on the wave function and the Bloch theory. Besides, the bandgap calculations of certain specific structures were carried out. Using the Abaqus dynamic simulation analysis software, the shockwave resistance of specific metamaterial structures and ordinary steel plates were compared and analyzed in terms of their response to stress and displacement. Consequently, the shockwave resistance and the results of bandgap calculations of the metamaterials were verified. The results showed that the bandgap model, constructed for the metamaterials, is highly accurate and the metamaterials with the structures of photonic crystal were found to be more resistant to shockwave. This investigation can provide a theoretical reference for future structural designs of shockwave-resistant metamaterials.
Research on the damage effect of semi-armor-piercing warhead on combined cabins of warships
Authors: Miao R , Wang W L , Du M H 
Published: July 2020

Abstract
Explosion test of 30kg Semi-armor-piercing warhead in the combined cabin of warship is completed. In the test, Upper and lower cabins are completely disintegrated. Cabins are broken in the weld zone. Maximum overpressure of lower cabin is 6.5 MPa and that of upper cabin is 0.6 MPa. By using numerical simulation method, influence of missile hole position and explosive charge velocity on damage effect is analyzed. Results show that difference of hole position will affect superposition of detonation products in cabin, thus changing position where the first structural fracture occurs in the cabin, leading to difference of damage. Increasing velocity of charge will make damage of positive direction bulkhead more serious, but damage degree of negative direction will be reduced. When velocity of charge exceeds 2 Ma, detonation products will not be able to affect cabin in negative direction of velocity.
Theoretical and Numerical Simulation of Small High-speed Projectiles Penetrating Brick Masonry
Authors: Li Z Q , Chen A J , Gong C A , Wang S , Yan W M , Wang C Z 
Published: July 2020

Abstract
The process of small high-speed projectiles penetrating brick masonry was studied. The cavity expansion theory used in the study of small high-speed projectile penetration was programmed and the penetration process was calculated. At the same time, LS-DYNA was used to simulate the mechanical process of small high-speed projectiles as they penetrate brick masonry. The results show that the numerical simulation results are more consistent with the theoretical calculation results; the numerical simulation of the finite boundary of the brick masonry and the mortar layer will cause some errors, making the brick masonry less resistant to small high-speed projectiles; When the masonry is compressible, the brickwork has less resistance to small high-speed projectiles; the larger the CRH value describing the geometry of the small high-speed projectile head, the maximum penetration depth and remaining of the small high-speed projectile The speed is greater.
The characteristics of fragments from embedded warhead
Authors: Gao Y G , Yan X M , Zhang B , Wu S Y , Xiao X , Feng Sh Sh 
Published: July 2020

Abstract
The Embedded warhead is a kind of warhead which is embedded into the target plate by its own kinetic energy and uses its effective fragments and whole or residual projectile to interdict the target. The fragments generated by the embedded warhead embedded in the target plate will impact the target plate and ricochet, which makes the dispersion of the fragments significantly different from that of warhead which is detonated in the air. However, there are no relevant researches which have been published. Therefore, in this paper, the dispersion of fragment from embedded warhead was investigated based on the experiment results, and the embedded warhead was detonated at center of the tail end. According to the experiment results, the fragments ricocheted from the target plate because the incident angle was too large. According to the statistics of fragments on the distribution plate, the average direction Angle of fragments went up (about 6°) due to part of fragments ricocheting from the target plate, which increased the damage effect of embedded warhead. The blocking diameter was 25m for human being. This study can provide a reference for the optimal design of embedded warhead.
Study on the influence of rigid wall surface on the bubble characteristics of underwater explosion
Authors: Meng L , Huang R Y , Qin J , Wang J X , Liu L T 
Published: July 2020

Abstract
In order to investigate the influence of rigid wall surface on the bubble characteristics of underwater explosion, the underwater explosion experiment under the boundary conditions of free surface and rigid wall surface was carried out on 2.5g cylindrical charge TNT in a 2×2×2m tank. The time history curves of shock wave and bubble pulsation were obtained by underwater pressure sensor, and the bubble pulsation process was observed by high-speed photography. The experimental results show that compared with the free surface underwater explosion, the shock wave peak pressure and the bubble pulse peak pressure in rigid wall surface underwater explosion are increased, and a large cavitation area appeared at the junction of rigid wall and water surface. After the bubbles contacted the rigid wall surface, the bubble morphology changed significantly, the first bubble pulsation period and the maximum radius of bubble expansion became larger. After the first bubble pulsation, the bubble partially collapsed and split into two parts, bubbles continued to pulsate in the direction of the rigid wall and the bottom of the water. Finally, combined with the experimental data of rigid wall surface at different explosion depths, the relationship between the first bubble pulsation period, the maximum bubble expansion radius and the explosion depth of 2.5gTNT under rigid wall conditions is given.