The Influence of the Rail Material on the Multishot Performance of the Rapid Fire Railgun

Abstract

The rapid fire railgun (RAFIRA), a unique railgun that can be operated in multishot mode, is well suited for the study of the influence of different rail materials on velocity and electrical contact of the armature and/or the wear of different rail materials. That is why we performed experiments with RAFIRA operated in multishot mode (firing rate of 50 Hz), using different rail materials (CuCr and Dural) and various shot energies. For these experiments, the shot energy for RAFIRA was raised, for the first time, up to the maximum energy at a disposal of 1.45 MJ per shot with projectile masses of over 120 g. In this way, we were able to show that the influence of the rail material depends on the applied shot energy: for low shot energies (<1 MJ), CuCr rails show better results in terms of velocities and exit times of the projectiles. This effect vanishes for high shot energies (>1 MJ). Whereas in terms of electrical contact, Dural rails show both less erosion and the capability to maintain a solid sliding contact until shot out for all energies applied.

A Comparison of C-Shaped and Brush Armature Performance

“…Before each shot either new copper (CuCr) rails (for experiments with C-shaped projectiles) or new aluminum (Dural) rails (for experiments with brush projectiles) were mounted into the launcher. In this way the same experimental conditions for each experiment and a good electrical contact between the corresponding projectiles and the rails were assured [8].…”

Magnetomechanical study of open-bore two-rail electromagnetic launcher

“…2.1). RAFIRA has eighteen power supplies, while fifteen of them are separated into three parts (Wild et al 2015). A five power supplies are for each shot at the main accelerator and two power supplies for each pre-accelerator.…”

Research Progress on Surface Damage and Protection Strategies of Armature–Rail Friction Pair Materials for Electromagnetic Rail Launch

“…Because of the interaction within the A&R, a series of complex surface behaviors occur on the surface of the A&R, such as Joule heating, arc electrical behavior [6][7][8], and changes in contact status (solid-arc-solid, solid-liquid-solid, and solid-solid contact). Several types of damage can occur on the A&R surface (friction and wear, deposition, gouge, grooving, transition, the arc ablation of the rail, and melting of the armature) [9][10][11][12][13][14]. These extreme service environments and complex surface behaviors extensively reduce service life and work efficiency, which has become a bottleneck that restricts the development of electromagnetic rail launch technology.…”