Shock to Initiation Characters of Heated Explosives with Different Confinement

Abstract

Heated explosives might undergo thermal expansion and/or phase transition, which affects their shock sensitivity. Therefore, investigating the effect of temperature on the shock initiation properties of explosives would provide valuable safety guidelines for their transportation and handling. In this study, an experimental detonation device that achieved homogeneous heating of the explosive test sample while avoiding unintended heat transfer to the donor was designed and constructed. The device allowed to perform flyer impact tests on PBXC10 at different temperatures and using different confinement conditions. The generated experimental pressure history curves were used to calculate the parameters of the I&G model and determine their relationships with the sample temperature. The fully parameterized I&G model enabled predicting the shock initiation properties of PBXC10 at temperatures where experimental data were unavailable. It was concluded that increased sample temperatures would lead to a shorter run distance to detonation, faster propagation of the detonation wave and enhanced shock sensitivity of the explosive. It was also demonstrated that unconfined PBXC10 exhibited significantly greater shock sensitivity compared to its partially and completely confined counterparts.

Comparative Analysis of Detonation Growth Characteristics between HMX‐ and TATB‐based PBXs

“…Recently, Wen et al [7] have performed a series of shock initiation experiments on PBXC03 and PBXC10 to obtain insitu pressure gauge data, in which the shock-wave loading was obtained by using an explosive plane-wave lens, and both the component proportions and the physical parameters of the used explosive samples [9] are listed in Table 4. In this paper, the new multi-components DZK reaction rate model is incorporated into a DYNA2D code to simulate numerically the shock ignition and the detonation growth processes of the PBXC03 and the PBXC10 explosives, respectively.…”

“…TATB (1,3,5-triamino-2,4,6-trinitrobenzene) belongs to the high thermal stabilized and insensitive high explosives, but it exhibits lower released energy [4][5][6]. Therefore, to satisfy the requirements of high performance and low sensitivity, mixing HMX and TATB at a certain ratio to prepare a HMX/TATB-based polymer bonded explosive (PBX), such as the commonly used PBXC03 (87 % HMX, 7 % TATB, and 6 % Viton by weight) [7,8] and the insensitive PBXC10 (25 % HMX, 70 % TATB, and 5 % Kel-F800 by weight) [7,9], is an effective method to balance the contradiction between energy release and sensitivity [10,11] and a direction for the formulation design of multi-component explosives. Moreover, it is well known that the detonation growth behaviors and the energy release characteristics of the HMX component is very much different from that of the TATB component, depending on each of their own reaction mechanism.…”