Magnetic Flux Compression by Magnetically Imploded Metallic Foils

A 136-kJ capacitor-bank energy source was used to implode metallic foils in a ``theta'' pinch. Aluminum foils accelerated by this scheme attained a velocity of 2.3 mm/μsec and a capacitive-to-kinetic energy conversion efficiency of 23%. An upper limit for the foil velocity depended upon the foil thickness and density, together with a parameter which accounted for electrical heating of the foil. This parameter was determined in exploding wire studies. Experiments with and without auxiliary injection of magnetic flux are described. Thick, imploding foils have been found to be capable of compressing enclosed magnetic flux to more than 2 MG.