Nature of the critical detonation diameter of condensed explosives

A new qualitative conception of the detonation mechanism in condensed explosives has been developed on the basis of experimental and numerical modelling data. According to the conception the mechanism consists of two stages: non-equilibrium and equilibrium. The mechanism regularities are explosive characteristics and they do not depend on explosive charge structure (particle size, nature of filler in the pores, explosive state, liquid or solid, and so on). The tremendous rate of loading inside the detonation wave shock discontinuity zone ( ca. 10 -13 s) is responsible for the origin of the non-equilibrium stage. For this reason, the kinetic part of the shock compression energy is initially absorbed only by the translational degrees of freedom of the explosive molecules. It involves the appearance of extremely high translational temperatures for the polyatomic molecules. In the course of the translational-vibrational relaxation processes (that is, during the first non-equilibrium stage of ca. 10 -10 s time duration) the most rapidly excited vibrational degrees of freedom can accumulate surplus energy, and the corresponding bonds decompose faster than behind the front at the equilibrium stage. In addition to this process, the explosive molecules become electronically excited and thermal ionization becomes possible inside the translational temperature overheat zone. The molecules thermal decomposition as well as their electronic excitation and thermal ionization result in some active particles (radicals, ions) being created. The active particles and excited molecules govern the explosive detonation decomposition process behind the shock front during the second equilibrium stage. The activation energy is usually low, so that during this stage the decomposition proceeds extremely rapidly. Therefore the experimentally observed dependence of the detonation decomposition time for condensed explosives is rather weak.

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Experience in Detonation Nano-Structures Coating Application Technologies using Condensed Explosives and Gas Mixtures

Indian Journal of Science and Technology ◽

10.17485/ijst/2016/v9i36/102014 ◽

2016 ◽

Vol 9 (36) ◽

Author(s):

Sergei Yurievich Ganigin ◽

Albert Rafisovich Gallyamov ◽

Maxim Vladimirovich Nenashev ◽

Andrey Yurievich Murzin ◽

Uljanitsky Vladimir Jurevich

Keyword(s):

Gas Mixtures ◽

Coating Application ◽

Nano Structures ◽

Condensed Explosives

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Channel effect mechanism in the detonation of condensed explosives

Combustion Explosion and Shock Waves ◽

10.1007/bf01261518 ◽

1966 ◽

Vol 2 (4) ◽

pp. 59-63 ◽

Cited By ~ 2

Author(s):

L. V. Dubnov ◽

L. D. Khotina

Keyword(s):

Effect Mechanism ◽

Channel Effect ◽

Condensed Explosives

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A Novel Melt Cast Composite Booster Formulation Based on DNTF/TNT/GAP-ETPE/Nano-HMX

Journal of Chemistry ◽

10.1155/2016/6521913 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Shuo Yu ◽

Hequn Li

Keyword(s):

Detonation Velocity ◽

Thermoplastic Elastomer ◽

High Energy ◽

Safety Performance ◽

Detonation Waves ◽

Small Scale ◽

Mass Ratio ◽

Critical Detonation Diameter ◽

Gap Test ◽

The Impact

To obtain the melt cast booster explosive formulation with high energy and low critical detonation diameter, melt cast explosives were designed by 3,4-bis(3-nitrofurazan-4-yl)furoxan (DNTF)/2,4,6-trinitrotoluene (TNT)/glycidyl azide polymer-energetic thermoplastic elastomer (GAP-ETPE)/nano-1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX)/Aristowax. Furthermore, the impact sensitivity, small scale gap test, rheological properties, propagation reliability, and detonation velocity were measured and analyzed. The results show that when the mass ratio of DNTF/TNT/GAP-ETPE/nano-HMX/Aristowax is 34.2/22.8/2/40/1, not only does it indicate excellent rheological property but it has a brilliant safety performance as well. Moreover, it can propagate the detonation waves successfully in the groove at 0.7 mm × 0.7 mm. When the charge density in the groove is 1.70 g·cm−3, its detonation velocity can reach 7890 m·s−1.

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