Initial experiments performed on MRL´s 1-cm square-bore railgun

Summary form only given. The Naval Research Laboratory (NRL) has initiated a program to investigate the operation of electric launchers for a variety of applications. Initial experiments have focused on a 1-cm square-bore, 1-m long railgun powered by a 0.5 MJ, ignitron-switched, capacitor bank. Aluminum foil fuses have been used to initiate plasma armatures for these experiments. Experiments studying the acceleration of the aluminum plasma armature by itself and of the armature pushing a 1-2 g lexan projectile have been performed. Comparisons with 1-D code predictions which include initial electrothermal effects have been made. Preliminary results at the 125 kJ bank energy level demonstrate acceleration of plasma armatures to >10 km/s along with secondary arc formation phenomena. Standing start solid projectile data show a boost to /spl sim/0.3 km/s provided by the initial electrothermal expansion of the aluminum foil followed by Lorentz acceleration of the plasma armature and projectile to >1.2 km/s.