Experimental study of solid armatures for EML applications

Capacitor-driven railgun test facilities of 150 kJ and 500 kJ with a 15-mm round bore were used to study the behavior of solid armatures. The parameters investigated include projectile design and material testing. It was found that the appropriate projectile design and material choice makes it possible to inject the current at the front side of the projectile and to distribute the current over the whole armature. The electrical resistance of the solid armature can be as low as a few tens of μΩ, and the rail erosion is significantly lowered compared to the plasma armature tests. The authors also present an acceleration calculation based on current measurements; for a current of 600 kA the acceleration value is about 2×10⁶ m/s²