Imploding Foil Liner Experiments on the MIG Pulse Generator

摘要

The energy density in the plasma column formed during the implosion of a cylindrical liner by the current of a powerful generator is largely determined by the radius of the liner. When the liner is accelerated to a given velocity, the liner's initial radius is proportional to the rise time of the generator current. With a current rise time of ∼ 100 ns and a liner velocity of $sim 3imes 10^{7} ext{cm}/mathrm{s}$ (before stagnation), it is necessary to choose a liner radius of about 1 cm. The paper presents experiments on imploding foil liners with a diameter of 1-2 mm when the current front through the liner is sharpened to several nanoseconds. In particular, upon implosion of a 1-mm-diameter liner from $2.5-mu mathrm{m}$-thick aluminum foil with a current of about 2 MA, a column of plasma with a diameter of not more than $70 mu mathrm{m}$ was obtained. An estimate of the energy density in the plasma column gives $geq 1.5imes 10^{8} mathrm{J}/ext{cm}^{3}$.