The optical diagnosis of electrical wire explosion under a microsecond current pulse.

Electrical wire explosions have many applications in scientific research and industry. Optical diagnosis is a powerful method to clarify the evolutionary process of such explosions. In this paper, an experimental platform was established to diagnose the optical radiation of electrical wire explosions. A low-jitter trigatron switch and its trigger generator were designed to ensure accurate synchronization. The spatial-temporal evolution process and the self-emission spectrum of electrical explosion plasmas from different wires (copper and tantalum) were obtained and analyzed. The optical diagnosis results indicated that the electrical explosion of copper wire was mainly characterized by the inhomogeneity of partial ionization and the rapid expansion of the discharge channel. The spectrum in the early discharge stage of the copper wire electrical explosion was a continuum, and most of the self-radiation spectral lines belonged to Cu I or Cu II. At the later stage of the plasma dissipation process, the continuous spectrum gradually transformed into a line spectrum. The development of the tantalum wire discharge channel was relatively uniform, and the plasma was mainly established in the gas-liquid mixed phase channel of the tantalum wire. The self-emission spectrum of the tantalum wire was always continuous, and the absorption process of line spectrum radiation was distinct.