A Study of Thin Foil Explosion

The explosion of thin flat and cylindrical foils has been studied on the BIN (270 kA, 100-ns rise time), XP (500 kA, 100-ns rise time), and COBRA (1.0 MA, 100-ns rise time) pulsed-power generators. On all three generators, hybrid and standard 4-wire X-pinches were used to provide soft X-ray radiography with better than 3- $\mu \text{m}$ spatial resolution and 1-ns temporal resolution. This enabled a detailed exploration of the dependence of the exploded structure of the foil on its initial structure and the current density flowing through it. With sufficient current density in the foils, bubbles were observed to form in the center of the foils; the higher the current density, the larger is the bubble diameters.