Study of the Interaction Between Electrostatic Discharge and the Granular Bed of the Ultra-sensitive Energetic Materials

Abstract

Paper is focused on the study of the effect of the capacitive Electrostatic Discharge (ESD) driven through the granular bed of the energetic material causing an initiation of the tested sample. The response of the sample is observed using an optical probe which converts the light emission in to the electrical signal. Sample is subjected to the well-defined ESD discharge using a volt-ampere discharge diagnostics which allows measuring of the exact amount of the electrostatic energy driven through the tested sample. The effect of the discharge energy on the reaction delay is studied in the two classes of the energetic materials. From the class of primary explosives were studied those were known to be very ESD sensitive: lead styphnate (LS) and silver acetilide (SAc). From the class of pyrotechnic compositions were studied these compositions: zirconium/potassium perchlorate (ZPP), zirconium/potassium perchlorate/potassium picrate (ZPPkP) and zirconium/red lead/viton (ZRV) and zirconium/red lead/nitrocellulose (ZRNc). The effect of the discharge energy was studied using different energy levels varying from the critical energies (minimum initiation energy-MIE) up to several multiples of critical energies. Even with the comparable critical energy levels for all of the tested substances, there was observed a large difference in the period between energy delivery and sample activation among these groups of EM. Pyrotechnic mixtures present clear evidence of dependence of reaction time on the arc energies. Compared with the primary explosives where the evidence of ignition delay dependence on the activation energy is not so obvious among the group of primary explosives especially for the silver acetilide.