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dc.contributor.advisorMary C. Boyce and Nicholas X. Fang.en_US
dc.contributor.authorKaynia, Nargesen_US
dc.contributor.otherMassachusetts Institute of Technology. Department of Mechanical Engineering.en_US
dc.date.accessioned2016-07-01T18:45:24Z
dc.date.available2016-07-01T18:45:24Z
dc.date.copyright2016en_US
dc.date.issued2016en_US
dc.identifier.urihttp://hdl.handle.net/1721.1/103494
dc.descriptionThesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2016.en_US
dc.descriptionCataloged from PDF version of thesis.en_US
dc.descriptionIncludes bibliographical references (pages 237-241).en_US
dc.description.abstractInspired by the undulating patterns found in different plant and biological cells in nature, this thesis explores the deformation-induced wrinkling instability transformation in the microstructure of composites with thin interfacial layers. The hybrid microstructure of a composite material has an essential influence on the effective properties and behavior of the composite. Hence, in this research, the principles and mechanics of interfacial layer instabilities are purposely designed to achieve sudden pattern transformations in the composite structure to generate new controlled multifunctional behavior. The wrinkling instability transformation is investigated in multilayered and networked composites consisting of relatively stiff interfacial layers or cells embedded in a soft matrix. Through analytical modeling, finite element simulations, and physical experiments, a comprehensive study is performed to elucidate: i) the conditions governing wrinkling, ii) the effect of wrinkling on local deformations, iii) the energy stored and dissipated in wrinkling composites, and iv) the change in the effective mechanical behavior of the composites. It is concluded that these properties are directly dependent on the composite's material and geometrical properties, and that composites can be designed to exhibit enhanced energy absorption (including energy storage and dissipation), stress mitigation effects, bilinear and multi-linear elastic stress-strain behavior, switchable effective stiffness, and can be used for energy harvesting applications. Design guidelines are presented to assist the process of deploying instability-transformation to tune, control, and switch the mechanical properties of multifunctional composite materials. Instability principles such as buckling and wrinkling are favorable mechanisms as they can be designed to be elastic and therefore reversible. The ability to alter and transform the microstructure enables on-demand tunability and active control of the composite's properties and attributes.en_US
dc.description.statementofresponsibilityby Narges Kaynia.en_US
dc.format.extent264 pagesen_US
dc.language.isoengen_US
dc.publisherMassachusetts Institute of Technologyen_US
dc.rightsM.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.en_US
dc.rights.urihttp://dspace.mit.edu/handle/1721.1/7582en_US
dc.subjectMechanical Engineering.en_US
dc.titleInstability-induced transformation of interfacial layers in composites and its multifunctional applicationsen_US
dc.typeThesisen_US
dc.description.degreePh. D.en_US
dc.contributor.departmentMassachusetts Institute of Technology. Department of Mechanical Engineering.en_US
dc.identifier.oclc952421303en_US


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