Explosion dynamics of thin flat foils at high current density

This paper presents characteristic features of the explosion of thin flat foils for currents and pulse risetimes ranging from 8 kA at 350 ns to 1000 kA at similar to 100 ns. Foils made of aluminum, copper, nickel, and titanium with thicknesses of 1-100 mu m are tested. Various diagnostics in the optical, UV, and x-ray spectral ranges are used to image the exploding foils from initial breakdown to complete destruction or pinching. It is shown that foil explosion is a complex process that depends on many factors, but features common to all foils are found that do not depend on the parameters of the generators or, accordingly, on the energy deposited in the foil: for example, the breakdown of flat foils under different conditions occurs at the edges of the foil. For the first time, the formation of a precursor over the central part of the foil is shown, which significantly changes the dynamics of the foil explosion. (C) 2022 Author(s).

Automated summary

This paper presents the characteristic features of the explosion of thin flat foils under different currents and pulse risetimes. The study shows that, regardless of the parameters, all foils have common features such as edge breakdown under different conditions, and the formation of a precursor in the central part of the foil significantly affects the dynamics of the explosion.