Preheating Sensitization of a TATB Composition Part one: Chemical Evolution

Abstract

We analyze the evolution of the sensitivity of a TATB composition after thermal cycles at elevated temperatures. Sensitization due to thermal cycles is of variable magnitude depending on the kind of the second stimulus (mechanical or thermal). In order to investigate the possible mechanisms which govern these phenomena, we perform an extensive study of the evolution of the chemistry and microstructure of our composition and we determine the sensitivity of our explosive to various stimuli after various temperature/duration cycles. This first paper is devoted to the study of TATB chemical evolutions. We present the results obtained for explosive decomposition, furazan generation, gas analyses and solid residue characterization.

Preheating Sensitization of a TATB Composition Part Three: Sensitization for Various Stimuli, Interpretation and Conclusions

“…The same behavior was observed for T2 composition [1]. In addition, chemical characterization of partially decomposed TATB [1,2] has shown that furazan concentration remains very low whatever the heating conditions are, which suggests a weak influence, if any, on sensitization.…”

“…To check this point we manufactured specific samples by mixing pristine pure TATB with 1% monofurazan and 0.5% difurazan. These concentrations are the maximum values to be considered according to the results of our chemical characterization of preheated TATB [1]. Of course, these samples could not be completely equivalent to cycled samples as furazan repartition was probably completely different from the cycled samples.…”

“…Moreover, applying thermal cycles before material shocking it results in significant permanent sensitization [1,8].…”

LX‐17 Thermal Decomposition‐Characterization of Solid Residues from Cook‐Off in a Small‐Scale Vessel Under Confinement

“…This would suggest the TATB ring itself does not fall apart but reacts further towards condensing into amorphous or weakly organized carbon networks. This, however, does not account for the formation of CO 2 , which is always seen in these reactions, even early on, as well as other oxides of carbon, C 2 N 2 , C 2 N 2 O, and other small molecules [2, 10, 12, 24, 96]. A key to this can be found in the gas monitoring during a modified SSVCT experiment [97].…”

“…Initial work addressed overall kinetics, realizing early the decomposition of a solid‐phase material is not well understood kinetically or mechanistically [1–5]. Attempts to characterize volatile decomposition products along with light gases led to the perspective benzo‐furazans and benzo‐furoxans are potentially stepwise formed and are part of the chain of decomposition reactions [6–15]. The overall mechanism was further developed for thermal modeling purposes showing the first part of the decomposition is the loss of water with the formation of mono‐benzo‐furazan (F 1 ), di‐benzo‐furazan (F 2 ), tri‐benzo‐furazan (F 3 ), and ultimately the ring system falling apart [5, 16–19].…”