Applicability limits of the DAX test in plastic bonded explosives

Abstract

The Disc Acceleration eXperiment (DAX) is one of the most recent experimental methods of performance characterization of new energetic materials. A cylindrical explosive charge accelerates a thin metallic disc and its velocity is measured continuously using photonic Doppler velocimetry. The detonation velocity is measured simultaneously. The DAX test can be used to obtain the Chapman-Jouguet (CJ) detonation pressure and to describe detonation products expansion using reduced amount of explosive. A series of DAX tests was performed at various charge diameters and disc thicknesses with Semtex 1 A plastic bonded explosive and sensitized nitromethane. The DAX-like evaluation was also applied to previously measured data of Semtex 1A and A-IX-1 explosives. The optimum disc thickness is determined by the disc to explosive mass ratio of 0.01–0.08. The repeatability of the Semtex 1 A detonation pressure results is about four times lower compared to the pressed and liquid explosives.