Experimental and Numerical Analysis of Postburst Dynamics in Electrically Exploding Single Copper Wire

Single copper wires have been electrically exploded at current densities of 10
⁷
-10
⁸
A/cm
²
using a pulse power setup consisting of a capacitor bank of 2.0 μF with discharge time period of 4.4 μs. A reproducible distinct kink or slope change is observed in measured postburst voltage fall across the wire under certain specific conditions of experimental parameters. To get an insight of possible mechanisms responsible for this, a 1-D numerical simulation has been utilized. The voltage profiles predicted by code appear to match well in shape and features with the experimentally recorded signals. The outcomes of numerical simulations indicate the formation of a density front inside the wire. Experimental analysis, carried out to explore the dynamics, predicts that this feature appears beyond the certain value of specific power. Specific power is found to be a more significant parameter than specific energy to obtain condition of such transient changes. For experiments reported here, the threshold value of specific power is found to be around 80 J/g/ns for copper. This work provides an insight into mechanisms involved in the explosion process of exploding wires.