Reducing Railgun Bore Erosion

Period of Performance: 03/05/1991 - 03/05/1993


Phase 2 SBIR

Recipient Firm

IAP Research, Inc.
2763 Culver Avenue Array
Dayton, OH 45429
Principal Investigator


Railguns have been limited to launch velocities of about 6 km/s, despite considerable developmental effort by many researchers. Researchers generally agree that secondary current paths rob current and therefore force from the main projectile accelerating armature. These secondaries result as highly ionized plasma left behind by the main armature begins to conduct. Evolutionary barrel design and bore materials improvements have had negligible affect on the secondary conduction phenomena. In the process of evaluating a rail design for erosion reduction during a SBIR Phase I, IAP discovered that compact plasma and hybrid armatures can be maintained, with virtually no secondary current conduction. IAP's approach employs serrated rails acting as a "finned radiator" which cools and expands plasma being leaked from the armature. Phase II will address the best serration geometry for achieving greater than 6 km/s.