Research on the sliding electrical contact of the high fire frequency launcher

Abstract

The sliding electrical contact between the armature and the rails is affected by the high current driving and the friction heating during the launching process, especially in high fire frequency applications. The contact performance is closely related to the resistance between the armature and the rails. A high fire frequency launcher was designed for the study of the sliding electrical contact. The pulsed power system consists of ten 100kJ pulse forming units with a total stored energy of 1MJ, and the length of the launcher is 1310 mm with a caliber size of 18 mm × 18 mm. Two types of armatures are adopted, one is the C-shaped armature, and another is the double C-shaped armature. Two 5g armatures can be launched at a frequency of 166Hz with a muzzle speed of 800m/s. The effect of contact resistance by the temperature rise can be calculated approximately with the heating. Experimental results shown that the contact resistance is seriously affected by the electromagnetic force and the contact temperature, the contact resistance of the second armature is between 0.8 mΩ–2.6mΩ, which is higher than that of the first armature (0.2mΩ–0.3mΩ).