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dc.contributor.advisorLuhrs, Claudia
dc.contributor.authorCook, Jamie E.
dc.dateDec-13
dc.date.accessioned2016-03-03T23:26:29Z
dc.date.available2016-03-03T23:26:29Z
dc.date.issued2013-12
dc.identifier.urihttp://hdl.handle.net/10945/48120
dc.descriptionApproved for public release; distribution is unlimiteden_US
dc.description.abstractThis thesis summarizes the failure mechanisms found in carbon nanofibers (CNF) and inorganic fullerene-type tungsten disulfide (IF-WS2) nanoparticles treated with diverse pressure loading methods. CNF were generated using nickel as catalyst and ethylene as carbon source, while IF-WS2 was acquired commercially. Approaches utilized to induce failure include the use of a gas gun, ultrasonic treatment and impact with military rounds. Samples were characterized using electron microscopy, powder x-ray diffraction, energy dispersive x-ray spectroscopy, and BET surface area analysis. CNF produced from nickel showed agglomeration from all testing methods but no evidence of fiber breakage or delamination. IF-WS2 failure modes observed were related, primarily, to the transition between 3D and 2D polymorphs, with subsequent agglomeration of the plate-like 2D structure, producing larger particle sizes. The secondary mechanism identified was delamination of IF-WS2, which, in contrast to the former, gave origin to smaller particulates. The failure modes identified herein were used to re-design the CNF material and test it using the gas gun. CNF with larger diameter distributions were grown from palladium catalyst, producing ultralow density carbon foam. This architecture presented viscoelastic properties that recovered the original shape after unloading, not showing evidence of failure under the gas gun test regime employed.en_US
dc.description.urihttp://archive.org/details/microstructuraln1094548120
dc.publisherMonterey, California: Naval Postgraduate Schoolen_US
dc.rightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.en_US
dc.titleMicrostructural analysis of the failure mechanisms of carbon nanofibers and inorganic fulerene-type tungsten disulfideen_US
dc.typeThesisen_US
dc.contributor.secondreaderHobson, Garth
dc.contributor.departmentMechanical and Aerospace Engineering (MAE)
dc.subject.authorCarbon nanofiberen_US
dc.subject.authorinorganic fullerene-type tungsten disulfideen_US
dc.subject.authorgas gun,ultrasounden_US
dc.subject.authormilitary roundsen_US
dc.subject.authoragglomerationen_US
dc.subject.authordelaminationen_US
dc.description.serviceLieutenant Commander, United States Navyen_US
etd.thesisdegree.nameMechanical Engineer and Master of Science in Mechanical Engineeringen_US
etd.thesisdegree.levelMastersen_US
etd.thesisdegree.disciplineMechanical Engineeringen_US
etd.thesisdegree.grantorNaval Postgraduate Schoolen_US


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