Abstract: The aim of this study is to examine the effect of slight density change on the short-duration shock initiation characteristics of triaminotrinitrobenzene (TATB)-based polymer bonded explosive (PBX). The PBX samples with different density are initiated by high speed Mylar flyer plates which are accelerated by an electric gun, and the displacement interferometer system for any reflector (DISAR) is used to determine the velocities of flyer plates. And then the shock initiation thresholds (50% probability of initiation) for the samples are calculated. The results show that a slight change in density leads to a substantial change of the shock initiation threshold: as the densities of the samples change from 1.885 g/cm³ to 1.905 g/cm³, the shock-initiation threshold increases from 5.38 GPa²·μs to 8.20 GPa²·μs correspondingly, and the samples become less sensitive to the shock. This indicates that the effect of slight density change on the shock initiation behavior of PBXs cannot be ignored, and suggests that it is necessary to keep the explosive density uniform (at least on the percentile order of magnitude). Key

Key words: TATB-basedPBXexplosive, shockinitiation, short-duration, electricgun