Investigation of the initial stage of exploding wire

Summary form only given, as follows. The dynamics of the initial stages of exploding wires have been investigated. A Maxwell 40167 Trigger amplifier, producing a maximum current of /spl sim/2 kA and voltage of /spl sim/75 kV, with current rise times of /spl sim/170 A/ns and 22 A/ns, was used in the explosion of W, Mo, Ti, Al, Au and Cu wires. The wires were 2 cm in length and 4-40 microns in diameter. Current, voltage, radial evolution, interferometry, shadowgraphy, self-luminosity imaging, and emitted light intensity were monitored in the experiment. The current and voltage were measured with a 2 GHz shunt and a 75 MHz high voltage resistive probe. Additional B-dot and D-dot measurements of current and voltage derivatives have been taken. Fast and slow explosion regimes have been investigated, with and without initial wire preheating. The evolution of wire diameter was determined using a laser back lighter and streak camera. Two significantly different modes of wire explosion have been found: fast and slow. Fast explosions demonstrate homogeneous deposition Joule energy inside of the wire and stronger light emission. The temporal behavior of the light emission is dependent on wire substance. The effect of magnetic field pressure confinement of explosion processes has been observed. A theoretical treatment of the experimental results will be presented.