The influence of insulating coatings upon single wire explosions

Summary form only given. Experiments have been initiated on the 1-MA Z-pinch generator at the Nevada Terawatt Facility to investigate the influence of insulating coatings on the ablation and energy deposition in current-carrying metallic wires. The Z-pinch loads used included single 50 μm Cu wires with and without polymer coatings, as well as pairs of such wires in a two-wire array configuration. The dynamics of these Z-pinches was diagnosed with laser shadowgraphy and X-pinch driven X-ray backlighting. It was observed that the ablation and the instability growth of the coated wires was delayed compared with that of the uncoated ones. Besides possible direct applications to enhanced energy deposition in Z-pinches, the coated exploding wires represent a platform for studying mixing in conditions that may be relevant to astrophysical systems and to directly or indirectly laser-driven fusion capsules.