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dc.contributor.authorKlein, Justinen_US
dc.date.accessioned2014-03-14T20:36:31Z
dc.date.available2014-03-14T20:36:31Z
dc.date.issued2010-05-04en_US
dc.identifier.otheretd-05122010-173824en_US
dc.identifier.urihttp://hdl.handle.net/10919/32666
dc.description.abstractProton exchange membrane fuel cells typically consist of stacks of membrane electrode assemblies sandwiched between bipolar plates, effectively combining the individual cells in series to achieve the desired voltage levels. Elastomeric gaskets are commonly used between each cell to insure that the reactant gases are isolated; any failure of a fuel cell gasket can cause the reactants to mix, which may lead to failure of the fuel cell. An investigation of the durability of these fuel cell seals was performed by using accelerated characterization methods. A hydrocarbon sealant was tested in five different environments to simulate fuel cell conditions. Viscoelastic properties of these seals were analyzed using momentary and relaxation compressive stress tests. Material properties such as secant modulus at 100% strain, tensile strength, and strain at failure were determined using dog-bone samples aged at several different imposed strains and aging times in environments of interest. Tearing energy was evaluated using trouser test samples tested under different rates and temperatures after various environmental aging conditions. Additionally, tearing tests were conducted on samples tested in liquid environment. A viscoelastic and mechanical property characterization of these elastomeric seals under accelerated aging conditions could help understand the behavior and predict durability in the presence of mechanical and environmental loading. Additionally, the effects of confinement have been evaluated for a bonded joint with varying thickness along the bonded direction. The Dreaming project is a glass art project in Fredrick, MD which incorporates such a varying thickness joint where thermal expansion of the adhesive has caused the glass adherend to break and debonding of the sealant. To examine this joint design, finite element analysis has been used to determine the effects of thermal expansion on such a complex geometry. Nine different test geometries have been evaluated to determine the effect of confinement coupled with thermal expansion on joint design with an elastomeric adhesive. Once evaluated, design changes were performed to try to reduce the loading while maintaining the general joint design. Results of this analysis can be used to determine the effects of confinement on a complex elastomeric joint.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartKlein_JE_T_2010.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectDegradationen_US
dc.subjectDurabilityen_US
dc.subjectLifetimeen_US
dc.subjectStress Relaxationen_US
dc.subjectConfinementen_US
dc.subjectStrain Energy Release Rateen_US
dc.subjectThermal Expansionen_US
dc.subjectElastomeren_US
dc.subjectVarying Thicknessen_US
dc.titleA Study of Durability for Elastomeric Fuel Cell Seals and an Examination of Confinement Effects in Elastomeric Jointsen_US
dc.typeThesisen_US
dc.contributor.departmentEngineering Mechanicsen_US
dc.description.degreeMaster of Scienceen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
thesis.degree.disciplineEngineering Mechanicsen_US
dc.contributor.committeechairDillard, David A.en_US
dc.contributor.committeememberMoore, Robert B.en_US
dc.contributor.committeememberCase, Scott W.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05122010-173824/en_US
dc.date.sdate2010-05-12en_US
dc.date.rdate2013-04-17
dc.date.adate2010-05-27en_US


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