Conference Paper

Experimental and Theoretical Analyses of Explosively-Formed Fuse (EFF) Opening Switches

Los Alamos Nat. Lab., Los Alamos, NM
DOI: 10.1109/MEGAGUSS.2006.4530692 Conference: Megagauss magnetic field generation and related topics, 2006 ieee international conference on
Source: IEEE Xplore


The EFF is used at Los Alamos as the primary opening switch for high current applications. It has interrupted currents from ~10 kA to 25 MA, thus diverting the current into low inductance loads. To understand and optimize the performance of full-scale experiments, many parameters were studied in a series of small-scale experiments, including: electrical conduction through the explosive products; current density; explosive initiation; insulator type; conductor thickness; conductor metal; metal temper; and on. The results show a marked inverse correlation of peak EFF resistance with current density. In this paper we postulate and refute a simple extrusion mechanism of EFF operation; demonstrate that the EFF switch has a near-ideal profile for producing flat-topped voltage profiles; and explore possible mechanisms for the degradation of small scale switch performance.

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Available from: Douglas Tasker, May 01, 2014
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