• Oxidation Process and Performance Promotion Mechanism of the Al-W Alloy Fuel

  HU Ao-bo, LIU Jin-ge, ZHAO Chao-yue, CHEN Peng, LI Peng, SUN Xing-yun, CAI Shui-zhou

  Online:November 27, 2023  DOI: 10.11943/CJEM2023204

  Abstract(1) HTML(60) PDF(4.80 M)( 2)

  Abstract:To elucidate the promotion mechanism of the oxidation performance of the Al-W alloy fuel， Al-20W and Al-30W alloy fuels were prepared by the aluminum thermal reduction and the ultra-high temperature gas atomization， and their oxidation process was studied by thermogravimetric/differential thermal analysis， X-ray diffractometer， and scanning electron microscope/energy dispersive spectrometer. The results indicate that Al-20W and Al-30W alloy fuels both contain metastable Al/W alloy phases， and the types and morphology of the Al/W alloy phases transform with increasing temperature. Al-20W and Al-30W alloy fuels have better thermal oxidation performance than pure Al fuel， with complete oxidation at 1300 ℃ and 1500 ℃， respectively， and all oxidation products WO₃ volatilizing. The presence of W enhances the oxidation performance of the Al-W alloy fuels. The promotion mechanism includes： the volatilization of WO₃ provides channels for O₂ to diffuse into the interior of the particles. As an “O atoms transport ship”， WO₃ transports O atoms to the pure Al phase， promoting the oxidation of the pure Al phase. WO₃ undergoes further chemical reactions and ultimately volatilize in a gaseous form， promoting the oxidation of the phase containing W.

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• Preparation and Performance of Al-LiH Composite Fuel

  WANG Fang, ZHANG Xin-peng, WANG Ding-cheng, LI Chun-tao, SUN Xin-ke, FENG Yong, LI Wei

  Online:November 27, 2023  DOI: 10.11943/CJEM2023197

  Abstract(6) HTML(84) PDF(1.77 M)( 23)

  Abstract:To improve the combustion efficiency of aluminum powders， Al-LiH composite fuels with mass contents of 3%， 5%， 10%， and 15% were prepared using the ball milling method， respectively. The sample structure， morphology， and particle size are characterized by X-ray diffraction （XRD）， scanning electron microscopy （SEM）， and particle size analyzer. The thermal oxidation performance was characterized using the DSC-TG. Finally， their combustion performance was investigated using the CO₂ laser ignition device， high-speed camera， and oxygen bomb calorimeter. The results show that LiH can be embedded into Al powder through the ball milling method， and the LiH content is a key factor affecting its microstructure， particle size， and particle size distribution. The addition of LiH increases the mass calorific value of fuel. At the same time， with the increase of LiH content， the combustion flame intensity of Al-LiH composite fuel increases and the ignition delay time significantly decreases. Among them， Al-3LiH and Al-10LiH composite fuels achieve second oxidation after the first oxidation. The analysis suggests that the second oxidation phenomenon is caused by the microexplosion phenomenon of Al-LiH composite fuel at high temperatures.

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• Quantitative CT Characterization Method for the Characteristic Parameters of Molding Granules

  ZHANG Cui, ZHANG Cai-xin, YANG Ya-fei, DAI Bin, DU Yu, CHEN Hua, ZHANG Wei-bin

  Online:November 16, 2023  DOI: 10.11943/CJEM2023142

  Abstract(29) HTML(124) PDF(1.30 M)( 98)

  Abstract:Quantitative characterization of its physical structure is crucial for regulating and enhancing the performance of PBX. Utilizing micro-CT， image processing， and statistical analysis， we researched the quantitative acquisition of characteristic parameters for molding granules. We conducted research on image processing and statistical analysis to quantitatively obtain the characteristic parameters of molding granules based on micro-CT. The characteristic parameters of TATB-based molding granules were characterized by this method， and an evaluation of the characterization method was conducted. The results suggest that this method can implement the quantitative characterization of the size， morphology， porosity， density， and packing characteristics of the molding granules. The granule size and sphericity of the TATB-based molding granules approximately follow the exponential Gaussian and Weibull distributions， respectively. The intrinsic density is 1.35 g·cm^-3， with a visible porosity of 2.3%（@spatial resolution 14.3 μm）， and a volume fraction of 0.69. Evaluation experiments demonstrate that the method exhibits good accuracy， stability， and repeatability. The characterization results of granule size are consistent with those of the sieving process， and the relative deviation of the characterization results of main characteristic parameters in different periods is less than 1%. The results of morphology and properties are relatively significantly influenced by the packing state of granules and the spatial resolution of micro-CT.

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• Influence of Straight and Spiral Groove Drainage Structures on the Evolution Characteristics of Underwater Gun Gas Curtain

  ZHANG Xue-min, ZHANG Xin-wei, YU Yong-gang

  Online:November 16, 2023  DOI: 10.11943/CJEM2023189

  Abstract(27) HTML(72) PDF(2.23 M)( 78)

  Abstract:A new type of cannon barrel with spiral grooves structure has been designed based on the principle of gas-curtain launching to reduce the launch resistance of underwater cannons. The low-resistance and high-speed launch of underwater cannons was achieved by the four spiral grooves opened on the inner wall of the barrel. A transient three-dimensional two-phase flow model of the gas-curtain launching and drainage process of underwater cannons was established， and the rationality of the model was verified. Based on this， numerical simulations of the drainage process of the spiral grooves structure were conducted， and the effects of straight grooves and spiral grooves on the gas-curtain drainage were compared and analyzed. The results show that during the initial expansion stage， the four gas jets rotate circumferentially and rapidly expand radially along the spiral grooves structure. Then， the jets interfere with each other and gradually converge， forming a columnar gas-curtain and starting· the cooperative drainage. During the formation of the gas-curtain， the spiral groove structure has a complex effect on the expansion velocity of the jet head， presenting an initial sharp decrease and subsequent decline with fluctuations. After the formation of the columnar gas-curtain， the velocity of the gas-curtain head increases nonlinearly. When the gas-curtain head expands to the outlet， the gas content of the spiral groove barrel increases by 9.3% compared to the straight groove barrel. Especially， the gas content reaches 100% within the range of 400 mm in front of the projectile.

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• Blasting Effects and of Lateral Annular Slit Charge and Application in Hard Rock Cutting

  CHENG Bing, WANG Quan, WANG Hai-bo, CHENG Yang-fan, ZONG Qi, WANG Meng-xiang

  Online:November 15, 2023  DOI: 10.11943/CJEM2023208

  Abstract(13) HTML(62) PDF(2.64 M)( 87)

  Abstract:A lateral annular slit charge was proposed in order to improve cutting effect in hard rock tuunels. Firstly， the blasting effects of the charge were analyzed theoretically. Then， the distributions of blasting strain and blasting crack after the charge blasting were studied through the model experiments. Finally， field tests were implemented to explore the applied efficacy of the charge. Results showed that the lateral annular slit charge could induce an energy accumulation effect at the slit position， which results in the rock mass at the slit position being subjected to stronger blasting loads and thus having stronger crack propagation ability. The lateral annular slit tube could reduce the blasting strain in the non-slit direction and increase the blasting strain in the slit direction. The strain distribution characteristic proves the energy accumulation phenomenon in the slit direction of the lateral annular slit charge. According to the macroscopic crack propagation， the crack propagation ability of lateral annular slit charge in the slit direction has been significantly improved. Compared with conventional column charge cutting blasting technique， the lateral annular slit charge cutting blasting technique could improve drivage efficiency and reduce cost in hard rock tunnels， which verifys that the lateral annular slit charge is preferred in hard rock tunnel cutting blasting.

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• Molecular Dynamic Studies on the Shock Responses of Energetic Crystal HMX with Cylindrical Voids

  ZHOU Ting-ting, LOU Jian-feng

  Online:November 13, 2023  DOI: 10.11943/CJEM2023167

  Abstract(36) HTML(140) PDF(3.12 M)( 127)

  Abstract:The relationship between crystal defects and hotspots formation of explosives under dynamic load is a hot research point in energetic materials. Understanding the mechanism of hotspots formation and its role in the ignition and sensitivity of high explosives are of great importance due to the needs of safety assessment of explosives and developing insensitive munitions. In this work， the ReaxFF reactive force field and molecular dynamics method were applied to investigate the dynamic responses of single crystal cyclotetramethylene tetranitramine （HMX） explosive with cylindrical voids under shock loading. Moreover， the effect of void size and double voids were studied. It is found that the shock induced collapse of voids includes three stages， namely， the plastic deformation on the upstream of the void， the movement of upstream atoms towards the centerline and the downstream of the void forming flowing atoms， and the collision of flowing atoms on the downstream. The main mechanism of hotspots formation is the collision of flowing atoms on the downstream that transforms kinetic energy into thermal energy leading to rapid temperature rise. The high temperature of hotspots initiates local chemical reactions， and the breaking of N─NO₂ bond in HMX molecule with NO₂ formation is the principal initial reaction mechanism. The collapse process and hotspots formation mechanism of cylindrical void is similar to spherical void， while the convergence effect is weaker and the velocity of formed flowing atoms is lower for cylindrical void， resulting in significantly low hotspot temperature and weak chemical reactions. Besides， the collapse of cylindrical void forms shear bands around， which was not observed for spherical void. With the increase of void size， the velocity of flowing atoms goes up， the shear bands are wider， and the hotspot temperature is higher and hotspot area is larger， leading to more violent chemical reactions. For the sample with two voids that are aligned along the shock direction with a distance of void radius， the collapse of voids is similar to single void. The shock pressure reduces when the shock wave propagates through the upstream void due to the reflected rarefaction wave. Therefore， the velocity of the flowing atoms formed during the collapse of the downstream void is smaller， and the temperature of the second hotspot is lower. The current findings are beneficial to comprehend the effects of crystal defects on hotspots formation and subsequent ignition of explosives and can provide physical mechanism and laws cognition to construct macro-theoretical models.

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• Application of Carbon Nanomaterials in Desensitizing Technique of Energetic Materials

  ZHAO Yang, JIN bo, PENG Ru-fang

  Online:November 10, 2023  DOI: 10.11943/CJEM2023177

  Abstract(48) HTML(222) PDF(2.09 M)( 131)

  Abstract:In order to utilize the performance advantages of carbon nanomaterials， this article summarizes the application of carbon nanomaterials in the desensitizing technology of energetic materials. The effects of typical carbon nanomaterials， such as graphite， carbon nanotubes， graphene and its derivatives， fullerene and its derivatives， on the reduction of impact， shock wave， and friction sensitivity of energetic materials， and explored the desensitization mechanism of different carbon nanomaterials was discussed. Finally， the development prospect of carbon nanomaterials in this field of desensitizing technique of energetic materials is forecasted. It is considered that optimizing the preparation process of carbon nanomaterials and energetic materials， deeply understanding the properties of carbon nanomaterials and conducting functional modification， regulating the interface interaction between carbon nanomaterials and energetic materials and further exploring the desensitization mechanism of carbon nanomaterial will be the focus of future research.

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• Mechanism Study on the Thermal Stability Difference of a Group of Isomeric Energetic Compounds

  WANG Rong, LINGHU Yao-yao, ZHANG Chao-yang, ZHONG Kai

  Online:November 10, 2023  DOI: 10.11943/CJEM2023194

  Abstract(41) HTML(170) PDF(2.69 M)( 128)

  Abstract:Isomerism is common in energetic compounds. Isomers may have differences in energy and safety performance. Investigating the mechanisms in these differences contributes to a deeper understanding of the structure-performance relationship of energetic compounds. The thermal decomposition mechanisms of three isomeric energetic compounds， 2，6-diamino-3，5-dinitro-1-oxide pyrimidine （LLM-105）， 3，5-diamino-4，6-dinitro-1-oxide diazine， and 1，4-dinitrofurazan ［3，4-b］ pyrazine （DNFP）， were studied using the self-consistent-charge density-functional tight-binding method （SCC-DFTB） under program heating and isothermal heating conditions. The results show that there is a strong hydrogen bond network in the LLM-105 crystal， enabling a molecular hydrogen transfer reaction accounting for 68.75% in the early stage of decomposition， which plays an important role in its high thermal stability； The skeleton structure of 3，5-diamino-4，6-dinitro-1-oxide diazine was prone to ring-opening through N─N bond cleavage under heating， resulting in lower thermal stability compared to LLM-105； The bond dissociation energy of DNFP for nitro group cleavage is 172.3 kJ·mol^-1， which is significantly lower than the other two isomers. Additionally， its fused-ring skeleton was also susceptible to ring-opening through C─C and N─O bond cleavage， resulting in the lowest thermal stability. In summary， the bond dissociation energy of the weakest bond in the molecule， the stability of the ring skeleton structure， and the hydrogen bond network of the crystal are important structural factors that determine the thermal stability of energetic compounds.

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• Reaction Molecular Dynamics Simulations of CL-20 Energetic Co-crystal under Shock

  WU Jun-ying, Fang Hui-xuan, Shang Yi-ping, Li Jun-jian, WANG Jian-yu, CHEN Lang

  Online:November 06, 2023  DOI: 10.11943/CJEM2023159

  Abstract(63) HTML(218) PDF(5.05 M)( 181)

  Abstract:Co-crystal technology is one of the effective methods to reduce the sensitivity of CL-20. Studying the chemical reaction of CL-20 co-crystal under shock is helpful to understand the shock reaction mechanism of CL-20 co-crystal， which is of great significance to the safety evaluation and analysis of explosives. In this study， the molecular dynamics method of ReaxFF-lg reaction force field and the non-equilibrium loading method were used to simulate the shock compression process of CL-20/DNT， CL-20/DNB and CL-20/MDNT co-crystals at 2-5 km·s^-1 shock velocity. The thermodynamic evolution characteristics， initial chemical reaction path and product information of energetic co-crystals after shock are obtained and compared with those of CL-20. It’s discovered that the three co-crystals of CL-20/DNT， CL-20/DNB and CL-20/MDNT have a certain degree of shock sensitivity reduction， and the order of shock sensitivity of the three co-crystals is CL-20/MDNT>CL-20/DNB>CL-20/DNT. The decomposition reaction of the three co-crystals all starts from the decomposition of CL-20， and the decomposition rate of CL-20 is faster than that of DNT， DNB and MDNT. At the shock velocity of 2 km·s^-1， the polymerization reaction of CL-20 co-crystal occurs first. The polymerization reaction between CL-20 and co-crystal ligand molecules is earlier than that between CL-20 molecules， and the reaction frequency is much higher than that between CL-20 molecules. At the shock velocity of 3 km·s^-1， the N─N and C─N bonds of CL-20 are first broken， and the cage structure is destroyed. At the same time， NO₂ is generated. NO₂ generated by the initial bond breaking of CL-20 further combines with the eutectic ligand molecules DNT， DNB and MDNT to reduce the concentration of the intermediate products of CL-20 reaction， so as to achieve the desensitization effect. At the shock velocity of 4 or 5 km·s^-1， the ring skeleton structure in CL-20 is directly destroyed， the C-N bond is broken， generating small molecular fragments， including N_2， NO₂， H₂， CO₂， H₂O and other products.

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• Effect of Boundary Constraints and Separation Surface Width on Separation Performance of Lead Linear Shaped Charge

  XIAN Ming-chun, ZHANG Yue-ping, LI Ning-rui, YIN Xin, WANG You, SUO Qi, LIU Ming-xing, CHEN Qi

  Online:November 06, 2023  DOI: 10.11943/CJEM2022266

  Abstract(30) HTML(92) PDF(2.13 M)( 176)

  Abstract:In order to study the effects of boundary constraint and separation surface width on separation performance of lead linear shaped charge， numerical simulation was used to analyze the factors affecting the separation of cast aluminum target plate after the explosion of lead linear shaped charge. The effects of free boundary constraint， fixed boundary constraint and slot width of separation surface on separation performance of lead linear shaped charge were obtained. Results show that the separation of brittle materials such as cast aluminum from lead linear shaped charge is the result of the joint action of jet penetration and high pressure detonation products. The boundary constraint has little influence on jet penetration and the deviation is generally less than 5%， but it has a great influence on the cracking process of the target plate. The strong fixed boundary constraint will limit the deformation and displacement of the material during the separation of the cutting cable， and then limit the cracking effect of high-pressure detonation products on brittle materials such as cast aluminum， which will increase the difficulty of subsequent separation. By appropriately increasing the width of the separation interface， the effect of boundary constraints on the separation performance of the cutting cable can be effectively reduced， and the separation reliability of the cutting cable can be improved. The 2.7 g·m^-1 lead linear shaped charge can reliably separate the ZL114A material with a thickness of 4.5 mm when the width of the weakening groove is ≥12 mm.

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• Electromagnetic Field Safety Threshold of Electro-explosive Devices

  YAO Hong-zhi, ZHANG Yun, DU Jing-li, ZHAO Tuan, JI Xiang-fei, ZHAO Jia, LI Rui

  Online:November 03, 2023  DOI: 10.11943/CJEM2022296

  Abstract(15) HTML(176) PDF(2.21 M)( 138)

  Abstract:In order to explore the electromagnetic field safety threshold of electro-explosive devices（EEDs） and provide a sensitivity evaluation benchmark for the study of electromagnetic compatibility and electromagnetic environmental effects of EEDs， based on the electromagnetic thermal coupling model of EEDs， white light interference method was used to test the electromagnetic field response characteristics of No.14 EED. The effect relationship between electromagnetic field coupling， self sensitivity， and electromagnetic response of EEDs was studied， a test method and calculation method for the electromagnetic field safety threshold of EEDs have been developed， and the electromagnetic field safety threshold of No.14 EED has been obtained within the frequency range of 10 kHz-18 GHz. The results indicate that the sensitive frequency range of No.14 EED is between 40 MHz and 1 GHz.

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• Non-destructive Characterization of Physical Parameters in Random Packing Systems of Explosive Molding Granules

  YUE Hong-li, ZHANG Cui, ZHANG Wei-bin

  Online:November 03, 2023  DOI: 10.11943/CJEM2023157

  Abstract(37) HTML(202) PDF(3.16 M)( 168)

  Abstract:The molding granule is an intermediate for polymer-bonded explosive （PBX） components. Characterization of the physical parameters of granular system is of great significance to understanding the influence of different granule structure on the performance of PBX components. X-ray computed micro-tomography （XCT） and CT image processing were used to non-destructively characterize physical parameters （including granule diameter， volume fraction， porosity， sphericity and intrinsic density） of the granular random packing systems. The average granule diameter of granular systems is up to 1.04 mm， the volume fraction is up to 68.7%， the lowest porosity is 1.04%， the highest average sphericity is 0.93， and the highest density is 1.44 g·cm^-3. Results show that the type of binder， explosive crystal composition， explosive crystal ratio and granulation process in the formulation of molding granules have important influences on the physical parameters of the granular system. Moreover， there is a correlation between physical parameters of granular systems. The more dispersed diameter distribution of granular system leads to the larger the average surface area of granules. The larger average granule diameter and lower average sphericity of granular system result in the higher porosity of the granules. The volume fraction of granular systems with larger average granule diameter is higher， and the volume fraction of the granule accumulation is independent of the sphericity when the average sphericity is large. This work provides a basis for understanding the physical parameters of random packing system of modeling granules and the in-depth study of the relationship between granular structure and material properties.

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• Reliability Design Method of Four-point Array Output Interface of Exploding Foil Initiator

  MA Wen-tao, MU Hui-na, QIN Guo-sheng, LIU Wei, ZENG Xiao-yun

  Online:October 26, 2023  DOI: 10.11943/CJEM2023126

  Abstract(53) HTML(118) PDF(1.83 M)( 249)

  Abstract:Aiming at the lack of reliability quantitative design method of the Exploding Foil Initiator （EFI）， the reliability design method for the Four-point Array output interface of EFI is studied. Firstly， based on the Stress-strength interference model， the reliability quantitative design method considering double margin coefficients is proposed， and the quantitative model between output performance parameters and reliability index is constructed. Then， the output performance of the output interface on different design parameters is simulated， and the quantitative models between the output performance parameters and structural design parameters is established. Finally， combined with the above two types of quantitative models， the structural parameters that meet the requirements of the output interface reliability design index of the four-point array slapper detonator are given. The results show that the method can effectively improve the reliability design accuracy of EFI’s output interface and then achieve accurate design.

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• Preparation and properties of nano B/NC/F₂₆₀₂ double-layer energetic fibers

  PENG Hao, SONG Xiao-lan, WANG Yi, CHENG Zhi-peng, AN Chong-wei

  Online:October 26, 2023  DOI: 10.11943/CJEM2023143

  Abstract(35) HTML(124) PDF(3.81 M)( 247)

  Abstract:In order to improve the dispersibility and energy output of nano-boron powder， n-B/NC/F₂₆₀₂ core-shell nanofibers were prepared by coaxial electrospinning method. The morphology of the samples prepared with different core solution mass fraction， shell solution mass fraction， working voltage， distance from needle to collector and injection rate were analyzed by scanning electron microscope（SEM）， and the optimum preparation conditions were explored. Scanning electron microscope （SEM）， X-ray photoelectron spectrometer（XPS） and infrared spectrometer （IR） were used to analyze the morphology of the samples prepared under the best preparation conditions. The combustion performance test， thermodynamic simulation and DSC-TG were used to analyze the combustion performance. The results show that the optimum preparation conditions is 15% of the core layer solution， shell solution mass fraction 15%， working voltage 16 kV， distance between needle and collector 12 cm， core flow rate 3.6 mL·h^-1， shell flow rate 6 mL·h^-1. The average diameter of the spinning product was 1.32 μm. The combustion performance test shows that the highest peak of combustion pressure is 0.51 MPa， and the average pressure boost rate is 0.61 MPa·s^-1， showing excellent combustion performance. Thermodynamic simulation showed that the average molecular weight of the product was 29 g·mo^-1， and the combustion was sufficient. DSC-TG showed that the weight gain of boron in n-B/NC/F₂₆₀₂ was 43.43% more than that of the original boron powder， and the peak exothermic temperature of boron in n-B/NC/F₂₆₀₂ was 41 ℃ lower than that of the original boron powder. The coaxial electrospinning method could better optimize the nanostructure of the fibers.

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• Design and Performance of Micro Safety and Arming Device Based on Laser Processing

  ZHANG Yun, JIANG Qian, LIU Wei, XIE Rui-zhen, REN Xiao-ming, LIU Lan

  Online:October 24, 2023  DOI: 10.11943/CJEM2023032

  Abstract(20) HTML(96) PDF(4.34 M)( 244)

  Abstract:In complex scenarios， the micro safety and arming device of initiating explosive device needs to have recoverable and anti-overload characteristics. Therefore， this study designed a metal-based electrothermal-driven micro safety and arming device based on laser processing. The finite element simulation was used to analyze the action characteristics of the nickel-based micro-electrothermal actuator. By adjusting the length and width of the hot arm and the cold arm of the double-arm U-shaped electrothermal actuator and the gap between the arms， the influence of them on the output displacement was explored. Through orthogonal experiments， the optimized ultra-fast laser processing parameters were obtained as follows： frequency 100 kHz， energy 113 μJ， and cutting speed 100 mm·s^-1， respectively. The ultra-fast pulse laser precision manufacturing of nickel-based electrothermal micro safety and arming device was realized. Finally， the performance verification platform of the safety and arming device was built， and the driving displacement and explosion-proof performance of the mechanism under different current excitations were verified. The results show that the driving displacement of the processed micro safety and arming device can reach 1084 μm under the excitation current of 8 A， and the encapsulated micro safety and arming device of initiating explosive device can effectively isolate the explosion in the explosive train.

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• Spalling Behavior of As-cast TiZrNbV Refractory High Entropy Alloy

  CHEN Rong, MA Rong, WANG Zheng, REN Ke-rong, ZHANG Si-yuan, TIAN zhan-dong

  Online:October 23, 2023  DOI: 10.11943/CJEM2023133

  Abstract(26) HTML(90) PDF(2.64 M)( 278)

  Abstract:The cast TiZrNbV refractory high entropy alloy （RHEA） has high structural strength and good energy release characteristics. As an energetic structural material， it needs to withstand complex dynamic load environments in engineering applications. Studying the spalling behavior of TiZrNbV refractory high entropy alloy and obtaining accurate dynamic constitutive parameters are vital for its engineering application. The spalling characteristics of TiZrNbV RHEA were studied by flat plate impact experiment using a 20mm light gas gun. Parameters such as spalling strength， Hugoniot elastic limit （HEL）， and plastic strain rate were obtained， based on the free surface velocity history. The recycled specimens were analyzed using scanning electron microscopy （SEM）， and the spalling characteristics of TiZrNbV RHEA at different strain rates were analyzed from both macro and micro perspectives. It was shown that the geometrically necessary dislocation of the samples significantly increased with the increase of loading velocity. The spalling strength of TiZrNbV RHEA increases with the loading strain rate and the loading stress， with values ranging from 0.93 GPa to 2.23GPa. The GTN-JC constitutive model parameters of TiZrNbV RHEA were obtained by calibrating the free surface velocity history of the spallation experiment with a flyer velocity of 580 m·s^-1. The spallation behavior of the sample under 610 m·s^-1 flyer velocity loading was calculated by using the fitted parameters. It was indicated that the free surface velocity curve of the spallation experiment performed well in simulating the spallation behavior of coarse-grained TiZrNbV RHEA. The simulation results show that the free surface velocity curve is consistent before the first tensile stage， which can be used for the dynamic analysis of sample spalling failure. The obtained parameters can provide reference for the engineering application of TiZrNbV RHEA.

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• Multifactor Analysis of Mechanical Response of PTFE/Al/SiC Based on Factorial Design

  WANG Rui-qi, LI Yu-chun, SONG Jia-xing, WU Jia-xiang, LI Rong-xin, HUANG Jun-yi

  Online:October 13, 2023  DOI: 10.11943/CJEM2023147

  Abstract(47) HTML(120) PDF(3.54 M)( 402)

  Abstract:To investigate the influence of SiC mass fraction， SiC particle size， Al particle size， and their interactions on the mechanical properties of PTFE/Al/SiC （PAS） reactive materials， a 2³ factorial design criterion was employed to design and prepare eight different compositions of PTFE/Al/SiC reactive materials， and quasi-static compression tests and split Hopkinson pressure bar （SHPB） experiments were conducted. Significant factors were selected using the t-value ranking method， and their contribution rates and disturbance trends were analyzed. Additionally， response surface methodology was employed to analyze significant interaction effects. The results indicate that a higher SiC mass fraction positively impacts the mechanical properties of PAS materials. With a sudden change of strain rate， SiC particle size exhibits opposite disturbance trends on the material mechanical response. The effect of Al particles on the mechanical response of the PAS material system is limited. Strong interaction effects between factors should not be overlooked. With low strain rate loading， the interaction between SiC mass fraction and SiC particle size is significant. When the SiC mass fraction is high and the particle size is small， the particle dispersion state and interfacial bonding strength can be optimized， thereby improving material mechanical response. With high strain rate loading， PAS materials with a higher SiC mass fraction exhibit higher dynamic mechanical response， and the interaction between SiC particle size and Al particle size is significant. When the particle sizes of SiC and Al are close， the dynamic response of the material can be effectively improved.

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• Relationship Between Networks Structure and Mechanical Properties of Highly Plasticized PEG Elastomer

  WANG Yao-xiao, WANG Xiao-ying, CHEN Chen, TAN Zhu-yun, ZHOU Xing

  Online:October 13, 2023  DOI: 10.11943/CJEM2023178

  Abstract(59) HTML(108) PDF(1.05 M)( 371)

  Abstract:To establish the correlation between the microstructure and mechanical properties of high nitrate plasticized polyethylene glycol （PEG） based polyurethane in nitrate ester plasticized polyether （NEPE） propellant， biuret triisocyanate （N-100） was used as a multifunctional curing agent and mixed with nitrate ester plasticized PEG for curing to prepare PEG elastomers with curing parameters ranging from 1.2 to 1.7. The microstructure of PEG elastomer crosslinked network was studied by uniaxial tension， X-ray diffraction， low field nuclear magnetic resonance and equilibrium swelling test methods. Furthermore， the effects of different network chain structures on the mechanical properties of PEG elastomer were analyzed. The results show that the PEG elastomer is amorphous due to its high plasticized properties. Meanwhile， the total ratio of suspended tail chains to free chains is more than 85%， the structural integrity of the crosslinked network is low， and the elastomer exhibits high elongation， low tensile strength and low initial modulus. Secondly， all the tensile strength and initial modulus of elastomer are positively correlated with the crosslinked chain density. The maximum elongation increases first and then decreases with the increase of physical temporary entanglement chain density. CU-5 elastomer with a curing parameter of 1.6 has the most complete cross-linked network. At the same time， the corresponding tensile strength is 0.80 MPa， and the maximum elongation is 1456%， which indicates that the mechanical properties are the best. Finally， the chain density measured by equilibrium swelling method and low field nuclear magnetic resonance satisfy the magnitude relationship of ν_L，A<ν_s<ν_L，A+B.

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• Numerical Simulation of Flow State on Extrusion Metering Section of Double-Base Propellant Plasticized with Supercritical-CO₂

  GU Han, YING San-jiu, HU Qi-peng, ZHANG He

  Online:October 11, 2023  DOI: 10.11943/CJEM2023138

  Abstract(57) HTML(116) PDF(2.03 M)( 397)

  Abstract:In order to understand the flow state of supercritical carbon dioxide (SC?CO2)?assisted double?base propellant within the metering section during extrusion, and to analyze the distribution and variations of parameters such as pressure, fluid velocity, shear rate and shear viscosity in the flow field, the CFD simulation software Polyflow was employed for simulating the flow state of the material in the metering section during SC?CO2?assisted double?base propellant extrusion. The results show that both fluid pressure and shear viscosity decrease with increasing process temperature, gas injection rate and solvent ratio. An increase in screw speed leads to a decrease in shear viscosity but a sharp increase in fluid pressure. The pressure on the outer wall of the fluid gradually increases in steps, with pressure at the cross?section exhibiting an approximately annular distribution, decreasing gradually from the inner wall of the barrel towards the screw surface. The shear viscosity at the cross?section forms a ring?shaped high?viscosity zone on the center of the screw. The closer the zone is to the inner wall of the barrel and the screw surface, the smaller the shear viscosity. Furthermore, changes in process parameters do not affect the distribution pattern of shear viscosity. The shear rate on the outer wall of the fluid increases with higher screw speed and concentrates at the thread. The maximum fluid velocity at the cross?section occurs near the thread, while the fluid velocity close to the inner wall of the barrel is minimal. As one moves away from the inner wall of the barrel and the screw surface, fluid velocity rapidly increases, with a greater gradient observed in zones closer to the screw surface and the inner wall of the barrel.

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• Determination of Composition and Content of Eluent Wastwater from Mixed NG/BTTN NitrateProduction by HPLC

  LI Lin-jun, CHEN Shi-cun, GUO Jia-yue, NING Wei, MENG Zi-hui, Guo Pei-pei, BI Jing, XUE Min

  Online:September 05, 2023  DOI: 10.11943/CJEM2023121

  Abstract(39) HTML(210) PDF(1.49 M)( 707)

  Abstract:In order to determine the composition and content of eluent wastewater from the production of nitroglycerin/1，2，4-butanetriol trinitrate （NG/BTTN） mixed nitrate， a high performance liquid chromatographic （HPLC） gradient elution method was carried out to detect washing wastewater. The chromatographic conditions were determined as follows： the stationary phase was C18 （250 mm×4.6 mm， 5 μm） column， the mobile phase was acetonitrile/water solution， and and the detection wavelength was 200 nm. The results showed that six organic compounds were detected in the scrubber wastewater. By fitting the retention time of the compounds and their linear relationship with the partition coefficient Log D （27 samples were taken within 7 days）， it was determined that in addition to NG and BTTN， the following compounds were present in the scrubber wastewater from the production of mixed NG/BTTN nitrates： 1，2-propanetricarboxylic acid dinitrate （30.58%-41.20%）， 1，3-propanetricarboxylic acid dinitrate （110.69%-135.14%）， 1，2，4-butanetricarboxylic acid （110.69%-135.14%）， 1，2，4-butanetriol-1，2-dinitrate （7.90%-10.63%）， and 1，2，4-butanetriol-1，4-dinitrate （22.55%-27.95%）， with the standard deviations lower than 10%， and the method was sampled for 40 times within 10 d. It was proved that the method is accurate， reliable and applicable， and meets the testing needs of industrial production.

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• Synthesis and Properties of 1-Hydroxy-N-（1H-1，2，4-triazol-3-yl）-1H-tetrazole-5-carboxamide

  LIU Jing, DONG Ya-qun, LI Miao, LIU Yu-ji, HUANG Wei, TANG Yong-xing

  Online:September 14, 2023  DOI: 10.11943/CJEM2023141

  Abstract(98) HTML(176) PDF( 713)

  Abstract:In order to explore novel nitrogen-rich heterocyclic energetic compounds， an amide bridged energetic compound 1-hydroxy-N-（1H-1，2，4-triazol-3-yl）-1H-tetrazole-5-carboxamide was synthesized from 5-cyano-1-（1H-1，2，4-triazol-5-yl）-1H-tetrazole through several steps involving amidoximation， diazotization， substitution and electrophilic addition. Its structure was fully characterized by nuclear magnetic resonance （NMR）， Fourier transform infrared spectroscopy （FT-IR） and elemental analysis （EA）. X-ray diffraction analysis （SC-XRD） was adopted to further confirm its structure； its thermal decomposition process was studied by differential scanning calorimetry （DSC） and thermogravimetry （TG）. The compound has a high onset decomposition temperature of 265 ℃ and shows good properties （detonation velocity： 8017 m·s^-1， detonation pressure： 23.1 GPa， impact sensitivity： 20 J， and friction sensitivity： 288 N）.

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• Preparation and Properties of Millimeter-sized Hollow Spheres for CL-20/HMX Co-crystal by Droplet Confined Crystallization

  LING Hui-jun, DUAN Xi-kai, CHEN Ling-yuan, REN Jun-ming, DUAN Xiao-hui

  Online:November 13, 2023  DOI: 10.11943/CJEM2023136

  Abstract(33) HTML(156) PDF( 119)

  Abstract:In order to investigate the effect of aggregation structure on the properties of hexanitrohexaazaisowurtzitane/octogen （CL?20/HMX） co?crystal， the droplet confined crystallization was used to prepare spherical CL?20/HMX co?crystal. The morphology and structure of the samples were characterized by field emission scanning electron microscopy （FE?SEM）， X?ray powder diffraction （XRD） and fourier transform infrared spectroscopy （FT?IR）. The properties of the samples were analyzed by thermal analysis， sensitivity and combustion tests. The results show that the spherical CL?20/HMX co?crystal was successfully prepared by this method. The diameter of the spherical CL?20/HMX co?crystal is 1.3-1.85 mm， the hollow ratio is about 40%， and the specific surface area is 6.890 m2·g-1. The exothermic peak temperature of spherical CL?20/HMX co?crystal is located at 245.8 ℃ ， the thermal decomposition activation energy （463.02 kJ?mol-1） and the critical temperature of thermal explosion （241.28 ℃） are higher than those of flake CL?20/HMX co?crystal， exhibiting the excellent thermal stability of spherical CL?20/HMX. The impact sensitivity is better than that of raw material and flake CL?20/HMX co?crystal， and the friction sensitivity falls between raw CL?20 and HMX， but lower than that of flake CL?20/HMX co?crystal. The ignition delay time is less than 8 ms and the combustion is efficient and stable， while the flake CL?20/HMX co?crystal， raw materials and their physical mixture exhibit flameless combustion.The construction of millimeter?sized hollow spheres for CL?20/HMX co?crystal has significantly improved the thermal stability，sensibility and combustion performances.

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Vol, 31, No.11, 2023    

>Energetic Express

• Energetic Express--2023No11

  Wang qian-you

  2023,31(11):1089-1089, DOI:

  Abstract(22) HTML(7) PDF(559.73 K)( 92)

  Abstract:

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>Preparation and Property

• Hydrolysis Mechanism and Synthesis Technology of 3，3′-Bi（1，2，4-oxadiazole）］-5，5′-diyldimethanol（BOD）

  XUE Da, WANG Xiao-jun, XU Zi-shuai, WANG Shou-fei, LI Yong-xiang, LIU Wei, CAO Duan-lin

  2023,31(11):1090-1096, DOI: 10.11943/CJEM2023108

  Abstract(20) HTML(2) PDF(1.05 M)( 73)

  Abstract:The reaction mechanism of intermediate 3，3′-Bis（1，2，4-oxadiazole）］-5，5′-diyldimethanol acetate （BODM） hydrolyzed to 3，3"-Bi（1，2，4-oxadiazole）-5，5"-diyldimethanol （BOD） was investigated by theoretical calculation. The synthesis process was optimized by single factor experiment and orthogonal experiment. The structure and properties of BOD were analyzed by XRD， FTIR， NMR and DSC. It was found that the reaction mechanism was the lone pair electrons in BODM —［O］— formed an OH…O hydrogen bond with H in H₂O， then the O—C bond in —［O］—［C═O］—broke， and the H and OH bonds in H2O formed —OH and —COOH group in —［O］— and —［C═O］—， respectively. and found that the crystal of BOD belong to the monoclinic system， the space group is C2/c， the cell angle α=90°， β=105.361（7）°， γ=90°， the cell volume v=774.9（2） A³， the density ρ=1.698 g·cm^-3. The melting point and decomposition peak temperature were 197.18 ℃ and 278.37 ℃， respectively. The results of single factor experiment showed that with the increase of reaction time and solvent， the yield of BOD increased at first and then became stable. With the increase of reaction temperature， the yield of BOD increased slowly and then decreased rapidly. With the increase of material ratio， the yield of BOD increased first and then decreased. In addition， the optimal process conditions were obtained by orthogonal experiment： BODM hydrolyzed in potassium carbonate methanol solution at 45 ℃ for 8 h， in which the molar ratio of BODM to potassium carbonate was 15∶1， and the yield was 94%. This study provides theoretical basis and experimental reference for scaling up and large-scale production of BOD.

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• Preparation and Properties of Self-assembled Stacking CL-20 Induced by Nitrified Graphene

  LUO Chuan-dong, LUO Qing-ping, JIA Hao-wei, WU Bo, LI Zhao-qian, DUAN Xiao-hui

  2023,31(11):1097-1104, DOI: 10.11943/CJEM2022260

  Abstract(12) HTML(2) PDF(1.89 M)( 75)

  Abstract:In order to improve the safety performance of hexanitrohexaazaisowurtzitane （CL-20）， the CL-20 with self-assembled stacking structures were prepared by the solvent-nonsolvent method using nitrified graphene （NG） as a crystallization inducer. The morphologies， structures， and thermal properties of the stacking structure CL-20 were characterized by field emission scanning electron microscopy （FE-SEM）， X-ray diffraction （XRD）， fourier transform infrared spectroscopy （FT-IR）， and synchronous thermal analyzer （DSC-TG） respectively， and their mechanical sensitivities were tested and analyzed. The results show that under the induction of different content of NG， CL-20 recrystallizes into square flake crystals， and self-assembles and stacks into petal-shaped， spiral-shaped， tower-shaped， and other structures. During the formation of the self-assembled stacking CL-20， the induction effects of NG are reflected in the adsorption effect of its sheet layer on CL-20 and the formation of hydrogen bonds between NG′s active functional groups with CL-20. Compared with the raw CL-20， the thermal decomposition temperature of the self-assembled stacking CL-20 is reduced by about 5 ℃， the maximum thermal decomposition enthalpy is increased by about 33%， and the mass loss is increased from 81% to 99%. The prepared self-assembled stacking CL-20 has a significantly lower mechanical sensitivity than that of the raw CL-20. When the NG content is 0.5%， the self-assembled petal CL-20 prepared by NG induction has the lowest impact sensitivity of 6 J.

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• Preparation of DAAF/Fluororubber Composite Microspheres by Droplet Microfluidic Technology

  ZHU Rui, LIU Yi, ZHANG Dong-xu, SHI Jia-hui, AN Chong-wei, WANG Jing-yu, WU Bi-dong

  2023,31(11):1105-1115, DOI: 10.11943/CJEM2023082

  Abstract(21) HTML(5) PDF(2.52 M)( 79)

  Abstract:Using droplet microfluidics technology， an aqueous solution of the active agent at a concentration of 0.5% was used as the continuous phase， and an ethyl acetate solution of DAAF was employed as the dispersed phase. DAAF/F2602 composite microspheres were prepared by fluid-focused microchanneling. The effects of two-phase flow rate ratio， concentration of dispersed phase， and type of active agent on particle morphology， particle size， and roundness of DAAF/F2602 composite microspheres were investigated. The optimal process conditions， including a suspension concentration of 4%， a two-phase flow rate ratio of 16∶1 and an active agent of CTAB， were obtained and compared with the aqueous suspension method. The results show that the DAAF crystalline shape of the samples obtained from two preparation methods are unchanged， the impact sensitivity is higher than 100 J， and the friction sensitivity is 0% and the friction sensibility are more than 360 N， indicating that the two samples have good safety performance. Among them， the particle sizes of DAAF/F2602 composite microspheres which obtained by the droplet microfluidization method were in the range of 20.22 to 53.85 μm， which were smaller than that obtained by the aqueous suspension method （121-356 μm）.Furthermore， the particle sizes distribution was observed to be more uniform. Thethermal decomposition exhibited a delayed peak temperature by 6.45 ℃， and the activation energy was increased by 6.12 kJ·mol^-1， which lead to improved thermal stability. The cone angle generated by the stacking of DAAF/F2602 composite microspheres which obtained by the droplet microfluidization method， is 34°. This angle is smaller than that of composite particles obtained by the water suspension method （40°）， which indicate better dispersion property.

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• Solubility and Dissolution Thermodynamics of Molecular Perovskite Energetic Material

  YUAN Ming-yu, LIU Qiang-qiang, SHANG Yu, ZHOU Wei, ZOU Li, GAO Hai-xiang, LIU Ying-le

  2023,31(11):1116-1123, DOI: 10.11943/CJEM2022284

  Abstract(19) HTML(4) PDF(661.41 K)( 88)

  Abstract:Solubility is an important parameter for the crystallization of molecular perovskite energetic materials （H₆N₂H₁₄）［NH₄（ClO₄）₃］（DAP-4）. In this work， the dissolution behaviors of DAP-4 at different temperatures （288-323 K） and in different solvents （ethanol， ethyl acetate， formic acid， deionized water， acetone， cyclohexane， methanol， acetonitrile， n-propanol） were studied by the gravimetric method. The dissolution models were established by the Apelblat equation and the λh equation， respectively. Meanwhile， the dissolution thermodynamic parameters （ΔH_d， ΔS_d， ΔG_d） were obtained by Van’t Hoff equation based on the thermodynamic principle of solid-liquid equilibrium. Results show that the solubility of DAP-4 is the largest in water and the smallest in ethyl acetate， which are increased with the increasing of temperature in different solvents. The fitting result of dissolution model from the Apleblat equation is better than that of the λh equation. Positive values of ΔH_d， ΔS_d， and ΔG_d indicate that the dissolving process of DAP-4 are non-spontaneous endothermic.

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>Propulsion and Projection

• Viscoelastic Properties and Constitutive Model of Double-Base Propellant

  XIA Jian-dong, XU Bin, LIAO Xin

  2023,31(11):1124-1133, DOI: 10.11943/CJEM2023145

  Abstract(23) HTML(1) PDF(1.73 M)( 83)

  Abstract:In order to characterize the mechanical response of double-base propellant， the viscoelastic properties and constitutive model of double base propellant were studied. Firstly， the viscoelastic properties of double-base propellant were investigated by tensile， compression and stress relaxation experiments with an observation of fracture surface. Then， a hyperelastic-viscoelastic model of double base propellant was established based on the Reduced Polynomial（N=5） model and Prony series. The parameters of the developed model were obtained by the experimental data. Finally， the hyperelastic-viscoelastic model of double base propellant was verified. The relatively error between the results of the simulation calculated by the hyperelastic model and the experiment for uniaxial tensile stress-strain is less than 5.01%. The relatively error between the results of simulation and experiment for stress relaxation is less than 6.49%. The developed hyperelastic-viscoelastic constitutive model of double-base propellant can well describe the mechanical properties of double base propellant， which provides a significant method for the research of mechanical properties of propellant.

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• Study on the Effect of Nitro Gradiently Distributed Propellant Charge for a Small and Medium Caliber Weapon

  LI Shi-ying, XIAO Zhong-liang, LI Yu, DING Ya-jun, SHI Yu-dong, ZHAO Jian-chun

  2023,31(11):1134-1140, DOI: 10.11943/CJEM2022243

  Abstract(15) HTML(2) PDF(1.25 M)( 81)

  Abstract:In response to the serious problems involving large smoke， flame and pungent smell known for a small and medium caliber weapon， the single base seven holes propellants were treated by chemical denitration method to prepare nitro gradiently distributed propellants with different denitration degrees. Their physicochemical， static burning properties， interior ballistic performance and emission hazard phenomenon were investigated. Based on the minimum free energy method， the influence of amount of camphor agent and the denitration degree on the combustion gases （CO， H₂） produced and unoxidized carbon were studied. The results show that with the increase of denitration degree， the explosion heat of propellants decreases from 4001 J·g^-1 to 3517 J·g^-1， the web thickness reduces from 0.92 mm to 0.89 mm， the content of stabilizer declines from 2.60% to 1.95%， the stability remains unchanged， B_m value increases to 0.66， and the progressive burning property enhances gradually； the better progressive burning of propellants， the higher initial velocity of the projectile under the same bore pressure condition was observed， the numerical expression and control method of ballistic performance for this investigated propellant were obtained based on the enantiomorphic coupling relationship established between the mass of charge， bore pressure and initial velocity； in comparison with the camphor-deterred propellants， the nitro gradiently distributed propellants demonstrated the promising characteristics of lower concentration of combustible gas， and less unoxidized carbon； in addition， the small flame， less irritating odour and low emission harmful phenomena are found for nitro gradiently distributed propellants during the firing test.

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>分析与检测

• Fast Measurement and Analysis of Photoacoustic Signal of Black Powder Generated by Focused Nanosecond Laser Pulse

  CHEN Yi-ru, SHEN Rui-qi, WU Li-zhi

  2023,31(11):1141-1149, DOI: 10.11943/CJEM2022167

  Abstract(12) HTML(7) PDF(997.73 K)( 98)

  Abstract:Photoacoustic signals were induced on slices of black powder and its components， which was radiated by 1064 nm laser pulses with 10 ns duration. The laser pulse energies were adjusted by regulating the number of fused silica plates on the laser path as attenuators. An optical fiber-based Michelson interferometer was utilized to detect the generated acoustic signals. Acoustic wave energy was estimated. A primary model was proposed to estimate the reaction rate of black powder. Detected phase changes were similar to each other， but the dimensions varied with laser pulse energy. Thermal reaction of blackpowder was not significant under laser radiation， but other reaction mechanism existed and enhanced the photoacoustic signal. Relationship between laser pulse energy and integration of absolute value of phase change is approximately linear. Reaction rate of black powder is positively related to laser energy， except for high-energy pulse. The maximum of reaction rate was about 20 mmol·s^-1， which was achieved when laser energy is around 10 mJ.

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• Quantitative Analysis of 2，6-diamino-3，5-dinitropyrazine-1-oxide Purity based on High Performance Liquid Chromatography

  CHEN Ling, ZHAO Yingbin, FENG Zhiqiang, ZHANG Yong, JIANG Lichun

  2023,31(11):1150-1157, DOI: 10.11943/CJEM2023009

  Abstract(12) HTML(1) PDF(934.86 K)( 77)

  Abstract:In order to rapidly analyze the product quality of 2，6-diamino-3，5-dinitropyrazine-1-oxide （ANPZO） and optimize the synthesis process， high-performance liquid chromatography （HPLC） method was developed to quantitatively analyze the purity of ANPZO. The effects of mobile phase composition， elution mode and detector wavelength on the resolution have been studied. The separation of ANPZO and its intermediate 2，6-diamino-3，5-dinitropyrazine （ANPZ） was accomplished by using C18 analytical column with size of 250×4.6 mm and 5 µm. The initial mobile phase composition was 0.1% trifluoroacetic acid and methanol （95∶5， v/v）. The methanol ratio was increased to 100% from 2 min to 7 min after the sample injection. Gradient elution was performed at a flow rate of 1.0 mL·min^-1， the column oven temperature was set at 30 ℃， and detection wavelength was 425 nm. The validation of the developed methods showed good linearity （R²=0.9996）， repeatability （%Area RSD%=0.30%） over the concentration range of 0.1 mg·mL^-1 to 0.6 mg·mL^-1. The limit of detection（signal/noise=3） and quantitation（signal/noise=10） of ANPZO were found to be 20 ng·g^-1 and 67 ng·g^-1， respectively. Therefore， the reported method is accurate， precise and sensitive， which can be used for the quality control of ANPZO.

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>Reviews

• Synthesis and Properties of N-bridgehead Energetic Fused Heterocycles

  QIAN Ya-dong, YIN Ping, PANG Si-ping

  2023,31(11):1158-1172, DOI: 10.11943/CJEM2022103

  Abstract(17) HTML(9) PDF(1.27 M)( 85)

  Abstract:Fused-ring energetic compounds， composed of two or more rings sharing two atoms and one chemical bond， have sizeable π-π conjugate structures and are a kind of popular new energetic materials. The polycyclic coplanar structure of energetic fused rings shows good molecular stability. Furthermore， the coplanar structure is featured with high heat of formation， significant ring tension， and high energetic performance. It can achieve a balance between high performance and molecular stability. With a C—N bond as the common building block， these nitrogen heterocycles have good density， stability， and numerous modifiable sites， which have become a new class of backbones in the field of energetic fused heterocycles. In this paper， the authors review the recent advance of synthesis， detonation properties， stability， and outlook of C—N type fused-ring energetic materials， which will be useful for the energetic community in future studies.

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• Review in the Regulation of Thermal Decomposition Characteristics of Three Typical Energetic Materials

  WANG Xiao-long, JU Rong-hui, ZHANG Yao-yuan, WU Qin, SHI Da-xin, CHEN Kang-cheng, LI Han-sheng

  2023,31(11):1173-1196, DOI: 10.11943/CJEM2022250

  Abstract(25) HTML(4) PDF(1.50 M)( 81)

  Abstract:Energetic materials are of great strategic value in both national defense and civil application. The thermal decomposition characteristics are one of the most important characteristics directly related to the effective application of energetic materials. It is of great significance to clarify the thermal decomposition behavior and mechanism of energetic materials for further improving the thermal decomposition efficiency and inhibiting their unstable decomposition. Three typical energetic materials， cyclotetramethylene tetranitramine （HMX）， hexanitrohexaazaisowurtzitane （CL-20） and 3，4-dinitrofurazanofuroxan （DNTF）， were studied. The basic physical and chemical properties related to the thermal decomposition characteristics were present， and the thermal decomposition behavior and mechanism were summarized， with emphasis on the structural characteristics of materials and the types of additives that influence the thermal decomposition. It is found that the removal of nitro group is the key step in the thermal decomposition， and the metallic materials rich in active sites and organic complexes with abundant active groups tend to interact with nitro groups to accelerate the thermal decomposition process. Inorganic non-metallic materials can also contribute to the decomposition behavior due to the large specific surface area and excellent gas diffusion ability. Three methods， including eutectic， coating and adding desensitizing agent， are widely used to improve the thermal stability of these three energetic materials. Based on the research of the thermal decomposition mechanism， the design and development of thermal decomposition accelerators and inhibitors can be carried out， which will effectively promote the innovative development of thermal application of energetic materials and become the focus of future research on the thermal decomposition characteristics of energetic materials.

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