Electromagnetic railgun extended-life bore material tests results

During the last five years the LTV Aerospace and Defense Company (LTVAD) has built and operated a Distributed Energy Source (DES) railgun laboratory. As part of the efforts to improve the efficiency of this gun design, research in the area of rail materials erosion phenomena has been one of the major concerns. Studies have been centered around the basic synergies associated with material´s erosion and railgun design; such as, the conductors, the insulators, the bore, the projectile and the gas environment. A data base, consisting of well over 200 shots, has been generated on the erosion rates of copper rails and various insulating sidewall materials at current densities ranging from 200 - 475 kAmps/cm. During these tests the insulating support structures suffered from considerably more erosion than the copper rails and will represent the largest deterent to repetitive operation of a railgun system. Consequently, research in the increased erosion resistance of insulating materials is an area of focus at LTVAD. This work was sponsored by the Army Ballistic Missile Defense Advanced Technology Center.