An Explosive High Voltage Closing And Opening Switch

The detonation front in an explosive is known to be electrically conducting. Previous reports have demonstrated at potentials of about 10kV that some explosives are good D.C. insulators, and independently that the detonation front is a low impedance with the impedance between electrodes rising after passage of the detonation front. We have pulse tested thin slabs of 3 explosives to 100kV under transformer oil without breakdown. A coaxial switch containing explosive has been tested by pulsing to 60kV under transformer oil. During this pulse the explosive was fired and demonstrated a switch closing action followed by an opening action equivalent to a repetition rate of approximately 70kHz. It also demonstrates that the high pressure explosion products behind the detonation front are insulating. The switch impedance during conduction was less than IQ for a current in excess of 1kA.