Studies of late time behavior of exploding wires using X-ray backlighting

Summary form only given. Fine W, Mo, Al, NiCr, Au, Ag, Ti, and other wires, exploded by a 4.5 kA amplitude, 1.4 /spl mu/s full period sinusoidal current pulse which damps in about 5 /spl mu/s, have been imaged using direct (point-projection) X-ray backlighting as late as 12 /spl mu/s after the start of the current pulse. The exploded wires, which ranged from 7.5 W to 13.5 /spl mu/m W, Au, Al and Mo to 25 /spl mu/m Ti and NiCr, were located about 6 cm away from two Mo X-pinch X-ray backlighter sources. The X-pinches as placed in parallel between the output electrodes of the 450 kA, 100 ns XP pulser at Cornell, each thereby producing a sub-nanosecond X-ray pulse. The source size is small enough to permit micron-scale spatial resolution images of the exploding wires on X-ray film. Changing the relative timing between the 4.5 kA current source and the XP pulser varied the image time. Wires were typically pulsed in pairs, reducing the peak current per wire accordingly. The behavior of the exploded wires on the microsecond time scale depends upon the material.