scholarly journals Predicting the impact sensitivities of energetic materials through zone-center phonon up-pumping

2021 ◽  
Vol 154 (6) ◽  
pp. 064105
Author(s):  
Adam A. L. Michalchuk ◽  
Jack Hemingway ◽  
Carole A. Morrison
Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3317
Author(s):  
Li ◽  
Du

The energy released by the active metal phase in fine-grained Fe/Al energetic materials enables the replacement of conventional materials in new types of weapons. This paper describes an experiment designed to study the energy-release characteristics of fine-grained Fe/Al energetic jets under impact loading. By means of dynamic mechanical properties analysis, the physical and chemical properties of Fe/Al energetic materials with specific content are studied, and the preparation process is determined. The energy-release properties of fine-grained Fe/Al jets subject to different impact conditions are studied based on experimental data, and energy-release differences are discussed. The results show that for fine-grained Fe/Al energetic materials to remain active and exhibit high strength, the highest sintering temperature is 550 °C. With increasing impact energy, the energy release of fine-grained Fe/Al energetic jets increases. At an impact-energy threshold of 121.1 J/mm2, the chemical reaction of the fine-grained Fe/Al energetic jets is saturated. The experimental data and microscopic analysis show that when the impact energy reaches the threshold, the energy efficiency ratio of Fe/Al energetic jets can reach 95.3%.


2008 ◽  
Vol 64 (1) ◽  
pp. 42-49 ◽  
Author(s):  
A. Meents ◽  
B. Dittrich ◽  
S. K. J. Johnas ◽  
V. Thome ◽  
E. F. Weckert

Experimental electron densities and derived properties have been determined for the two energetic materials CL-20 (3,5,9,11-tetraacetyl-14-oxo-1,3,5,7,9,11-hexaazapentacyclo-[5.5.3.02,6.04,10.08,12]pentadecane), and FOX-7 (1,1-diamino-2,2-dinitroethylene) from single-crystal diffraction. Synchrotron data extending to high scattering angles were measured at low temperature. Low figures-of-merit and excellent residuals were obtained. The Hansen & Coppens multipole-model electron density was compared with results from theoretical calculations via structure factors simulating an experiment. Chemical bonding in the molecules is discussed and a topological analysis gives insight especially into the character of those bonds that are thought to play a key role in the decomposition of the molecules. A comparison of theoretical and experimental electrostatic potentials shows no obvious evidence supporting earlier findings on other nitroheterocyclic molecules that electron-density maxima near the C—NO2 bonds mapped on the electron-density isosurface can be correlated with impact sensitivities. For FOX-7 periodic Hartree–Fock calculations were performed to investigate the influence of the crystal field on the electron density distribution.


Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 133
Author(s):  
Weiqiang Pang ◽  
Chongqing Deng ◽  
Huan Li ◽  
Luigi T. DeLuca ◽  
Dihua Ouyang ◽  
...  

As a hot research topic, nano-scale energetic materials have recently attracted much attention in the fields of propellants and explosives. The preparation of different types of nano-sized energetic materials were carried out, and the effects of nano-sized energetic materials (nEMs) on the properties of solid propellants and explosives were investigated and compared with those of micro-sized ones, placing emphasis on the investigation of the hazardous properties, which could be useable for solid rocket nozzle motor applications. It was found that the nano-sized energetic materials can decrease the impact sensitivity and friction sensitivity of solid propellants and explosives compared with the corresponding micro-sized ones, and the mechanical sensitivities are lower than that of micro-sized particles formulation. Seventy-nine references were enclosed.


2020 ◽  
Vol 1 (1) ◽  
pp. 40-49 ◽  
Author(s):  
Xiaoxue Xiong ◽  
Xudong He ◽  
Ying Xiong ◽  
Xianggui Xue ◽  
Haijun Yang ◽  
...  

2020 ◽  
Vol 26 (4) ◽  
Author(s):  
Tomas L. Jensen ◽  
John F. Moxnes ◽  
Erik Unneberg ◽  
Dennis Christensen

Abstract In order to predict the impact sensitivity of high explosives, we designed and evaluated several models based on the trigger linkage hypothesis and the Arrhenius equation. To this effect, we calculated the heat of detonation, temperature of detonation, and bond dissociation energy for 70 energetic molecules. The bond dissociation energy divided by the temperature of detonation proved to be a good predictor of the impact sensitivity of nitroaromatics, with a coefficient of determination (R2) of 0.81. A separate Bayesian analysis gave similar results, taking model complexity into account. For nitramines, there was no relationship between the impact sensitivity and the bond dissociation energy. None of the models studied gave good predictions for the impact sensitivity of liquid nitrate esters. For solid nitrate esters, the bond dissociation energy divided by the temperature of detonation showed promising results (R2 = 0.85), but since this regression was based on only a few data points, it was discredited when model complexity was accounted for by our Bayesian analysis. Since the temperature of detonation correlated with the impact sensitivity for nitroaromatics, nitramines, and nitrate esters, we consider it to be one of the leading predictive factors of impact sensitivity for energetic materials.


2015 ◽  
Vol 1096 ◽  
pp. 407-412
Author(s):  
Hui Hu ◽  
Miao Miao Li ◽  
Bao Shan Wang

Organic CHNO-containing high energy density materials have been widely used for storing large amounts of the chemical energies which can be rapidly transformed into heat upon various external perturbations during detonation. The sensitivity of the energetic materials is subjected to considerable concern for safety and maintenance. Periodic density functional theory with the all-electron basis sets were employed in this work to unravel the impact, friction, and electric-fields induced decomposition of HMX. The minimum energy paths for the N−NO2homolysis reactions of HMX in the bulk and gas phases were obtained. The surface-enhanced effect on the decomposition of HMX were calculated for both (010) and (100) surfaces. A general theoretical scheme has been proposed to assess the intrinsic mechanic and electrostatic sensitivities of the pure energetic materials.


2014 ◽  
Vol 924 ◽  
pp. 105-109 ◽  
Author(s):  
Guo Ping Li ◽  
Lian Hua Shen ◽  
Bao Ming Zheng ◽  
Min Xia ◽  
Yun Jun Luo

AP-based nanolimit growth energetic materials (NLGEM) were prepared by using SiO2 gel as nanolimit growth skeleton materials and using sol-gel method combining solution crystallization to make AP recrystallized in the nanopores of SiO2 gel skeleton to form AP/SiO2 NLGEM. The chemical and physical structure and properties of AP/SiO2 NLGEM were studied in detail. AP with nanoscale particles size range from 69nm to108nm was recrystallized in the pore of SiO2 gel skeleton and the particle size of AP increased with the amount of AP in NLGEM increasing. Moreover, the preparation method didnt change the crystal form of AP and bring impurities to NLGEM. The decomposition of AP/SiO2 NLGEM was a one-step process, which was indicated its decomposition was more concentrate than pure AP and AP/SiO2 simple physical mixture (AP/SiO2 SPM), whose decomposition was a two-step process. At the time, the decomposition heat of AP/SiO2 NLGEM was higher than that of pure AP and AP/SiO2 SPM. The sensitivity of AP/SiO2 NLGEM was lower than those of the pure energetic components and physical mixtures according to the impact sensitivity test.


2009 ◽  
Vol 16 (5) ◽  
pp. 895-901 ◽  
Author(s):  
Miroslav Pospíšil ◽  
Pavel Vávra ◽  
Monica C. Concha ◽  
Jane S. Murray ◽  
Peter Politzer

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