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dc.contributor.advisorRavi-Chandar, K.en
dc.creatorManley, Matthew Halperinen
dc.date.accessioned2011-11-01T21:42:25Zen
dc.date.available2011-11-01T21:42:25Zen
dc.date.issued2010-08en
dc.date.submittedAugust 2010en
dc.identifier.urihttp://hdl.handle.net/2152/ETD-UT-2010-08-1946en
dc.descriptiontexten
dc.description.abstractRailguns undergo excessive wear between the projectile and the electromagnetic launcher rails due to the hypersonic relative motion and very large current density involved. The wear effects at the small-scale on the rail-armature interface are not well known but need to be examined in order to support the development of a multishot launcher. Proposed contact regimes in the surface asperity interactions include solidsolid contact, liquid-metal lubricated contact, and arcing. In the present work, a modified Mesoscale Friction Tester (MFT) equipped with a probe and substrate was used to investigate experimentally the arcing and friction conditions that the rail-armature interface would experience. Copper probes with a range of radii of curvature were electrochemically etched and polished to submicrometer roughness. The minimum electrode distances for arcing to occur was found in air at atmospheric pressure and led to a modified Paschen curve where field emission of electrons was the dominant physical mechanism as opposed to Townsend avalanche of ionized gas. Arcing erosion was studied by varying the current, number of strikes, dwell time, and nearest electrode positions horizontally and vertically. Copper-copper friction with a constant normal force resulted in reduced wear when applying a constant current between the electrodes.en
dc.format.mimetypeapplication/pdfen
dc.language.isoengen
dc.subjectRailgunen
dc.subjectRail gunen
dc.subjectFrictionen
dc.subjectContact regimeen
dc.subjectCurrent densityen
dc.subjectArmatureen
dc.titleExperimental investigation of the effects of electrical currents in small-scale contact regimesen
dc.date.updated2011-11-01T21:43:28Zen
dc.identifier.slug2152/ETD-UT-2010-08-1946en
dc.contributor.committeeMemberSatapathy, Sikhandaen
dc.description.departmentAerospace Engineeringen
dc.type.genrethesisen
thesis.degree.departmentAerospace Engineeringen
thesis.degree.disciplineAerospace Engineeringen
thesis.degree.grantorUniversity of Texas at Austinen
thesis.degree.levelMastersen
thesis.degree.nameMaster of Science in Engineeringen


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