Response of Primary Explosives to Gaseous Discharges in an Improved Approaching-Electrode Electrostatic Sensitivity Apparatus.

摘要

This report describes an improved, approaching-needle electrostatic sensitivity apparatus as well as the instrumentation used for measuring time-dependent gaseous discharge characteristics. It is shown that the addition of resistances in series with the gap changes the nature of the discharge as found previously for the fixed-gap apparatus. The energy delivered from the storage capacitor to the gap is 3-6% for an arc discharge and 15-25% for a spark discharge. The initiation of basic lead styphnate, RD1333 lead azide, and tetracene by gaseous discharge is a strong function of the energy delivery rate. The threshold initiation energy values were considerably less in the spark mode (long duration discharge) than in the oscillatory or arc modes (Short duration discharges). The ranking of the sensitivity of these three primary explosives did not vary with the mode of discharge as found previously for the fixed-gap, parallel-plate apparatus. To meet the need for a single, standardized electrostatic sensitivity apparatus and test method able to distinguish between primary, booster or main charge explosives and to rank the sensitivity of explosives, the approaching needle apparatus used in this study, with slight modifications, is proposed to the Joint Service Committee for adoption as a Tri-Service standard. (Author)