Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficien...Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical applications.Herein,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion reactivity.The reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb calorimetry.Due to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of Al.The reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to B.This work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.展开更多
Interaction of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)/ammonium perchlorate(AP) and its effect on mechanical sensitivity may result in some restrictions for the application of AP/HMX system in high energetic weapo...Interaction of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)/ammonium perchlorate(AP) and its effect on mechanical sensitivity may result in some restrictions for the application of AP/HMX system in high energetic weapon system. In this work, impact sensitivity test is used to study the effects of wax coating of HMX, AP and aluminum(Al) powder on sensitivity properties of HMX/AP/Al mixtures.Thermogravimetry-differential scanning calorimetry(TG-DSC) analysis has been developed to investigate the mechanism of interaction between HMX and AP during the course of thermal decomposition of HMX/AP/AI mixtures. The results show that severe interaction effect exists between AP and HMX, which causes the impact sensitivity(H_(50)) to become smaller. The impact energy(E_(50)) of mixture can be improved under the circumstances of effective separating HMX from AP by surface coating with Wax. AP may firstly engender low-temperature decomposition under the circumstance of external heat or mechanical impact, which causes the exothermic peak of HMX forward shift about 28 C. The gaseous product releasing from thermal decomposition of HMX accelerates further decomposition of AP. For HMX/AP composite system, the interactive catalysis effect between AP and HMX can be eliminated mostly by adding a great deal of Al powder(i.e. above 30%).展开更多
Batch preparation of nano-HMX was achieved via a mechanical trituration method. The morphology and particle size of nano-HMX and raw RDX were characterized using SEM. Then nano-HMX was used in a formulation of composi...Batch preparation of nano-HMX was achieved via a mechanical trituration method. The morphology and particle size of nano-HMX and raw RDX were characterized using SEM. Then nano-HMX was used in a formulation of composite modified double base propellant containing RDX. The method is to use nanoHMX to replace the RDX in the formulation by 10% gradually with the total mass content of RDX and HMX unchanged. The burning rate, mechanical sensitivity and mechanical property of propellant strands with different mass content of nano-HMX were tested. The results indicate that the 30% content of nanoHMX has the best comprehensive performance which can be used as an improvement of the existing formula. A possible mechanism of action was discussed.展开更多
基金the National Natural Science Foundation of China(Grant Nos.T2222027,12202416 and 12272359).
文摘Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical applications.Herein,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion reactivity.The reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb calorimetry.Due to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of Al.The reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to B.This work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.
基金supported by the National Nature Science Foundation of China(Nos.11402238,11502243 and 11502245)
文摘Interaction of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX)/ammonium perchlorate(AP) and its effect on mechanical sensitivity may result in some restrictions for the application of AP/HMX system in high energetic weapon system. In this work, impact sensitivity test is used to study the effects of wax coating of HMX, AP and aluminum(Al) powder on sensitivity properties of HMX/AP/Al mixtures.Thermogravimetry-differential scanning calorimetry(TG-DSC) analysis has been developed to investigate the mechanism of interaction between HMX and AP during the course of thermal decomposition of HMX/AP/AI mixtures. The results show that severe interaction effect exists between AP and HMX, which causes the impact sensitivity(H_(50)) to become smaller. The impact energy(E_(50)) of mixture can be improved under the circumstances of effective separating HMX from AP by surface coating with Wax. AP may firstly engender low-temperature decomposition under the circumstance of external heat or mechanical impact, which causes the exothermic peak of HMX forward shift about 28 C. The gaseous product releasing from thermal decomposition of HMX accelerates further decomposition of AP. For HMX/AP composite system, the interactive catalysis effect between AP and HMX can be eliminated mostly by adding a great deal of Al powder(i.e. above 30%).
基金financially supported by the Youth Science and Technology Innovation of China North Chemical Industry Group Co.,Ltd.Natural Science Foundation of China(Project No 50972060 and No 51606102)+4 种基金the Weapon Research Support Fund(62201070804)Qing Lan ProjectEnvironmental Protection Scientific Research Project of Jiangsu Province(2016056)a Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,the Shanghai Aerospace Science and Technology Innovation Fund(SAST2015020)Basic Product Innovation Technology Research Project of Explosives
文摘Batch preparation of nano-HMX was achieved via a mechanical trituration method. The morphology and particle size of nano-HMX and raw RDX were characterized using SEM. Then nano-HMX was used in a formulation of composite modified double base propellant containing RDX. The method is to use nanoHMX to replace the RDX in the formulation by 10% gradually with the total mass content of RDX and HMX unchanged. The burning rate, mechanical sensitivity and mechanical property of propellant strands with different mass content of nano-HMX were tested. The results indicate that the 30% content of nanoHMX has the best comprehensive performance which can be used as an improvement of the existing formula. A possible mechanism of action was discussed.
