Improvement of Electromagnetic Railgun Barrel Performance and Lifetime by Method of Interfaces and Augmented Projectiles

<p>Several methods of increasing railgun barrel performance and lifetime are investigated. These include two different barrel-projectile interface coatings: a solid graphite coating and a liquid eutectic indium-gallium alloy coating. These coatings are characterized and their usability in a railgun application is evaluated. A new type of projectile, in which the electrical conductivity varies as a function of position in order to condition current flow, is proposed and simulated with FEA software. The graphite coating was found to measurably reduce the forces of friction inside the bore but was so thin that it did not improve contact. The added contact resistance of the graphite was measured and gauged to not be problematic on larger scale railguns. The liquid metal was found to greatly improve contact and not introduce extra resistance but its hazardous nature and tremendous cost detracted from its usability. The simulated resistivity augmented projectiles were able to mitigate harmful current build-up on the back of a projectile using different conductivity gradients. Within the range of conductivity of aluminum alloys no simulated gradient was able to fully level the current density, however, once the range was expanded to include the lower conductivity of titanium, nearly uniform current density was achieved.</p>

Name thesis:degree_name

MS in Aerospace Engineering

Discipline thesis:degree_discipline

Aerospace Engineering

Year dc:date.available

2013

Author dc:creator

• Pavlov, Aleksey D

Contributors dc:contributor

• Kira Abercromby

• railgun
• electromagnetism
• liquid metal
• graphite coating
• augmented projectiles
• Other Aerospace Engineering

Identifier

10.15368/theses.2013.136

OAI identifier oai:identifier

oai:digitalcommons.calpoly.edu:theses-2069