Publications by authors named "Hyung-ick Kim"

There have been a number of theoretical and experimental studies on tensile properties of carbon nanotubes (CNT), reporting the Young's modulus of the individual CNT up to 1 TPa. Although CNT shows the promise to be used as reinforcement in a high modulus/strength composite material, it exhibits quite disappointing in terms of modulus or strength. Along with recent advance in CNT growth technique, we will be able to directly measure tensile properties of millimeter-long MWCNTs.

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The local buckling behavior of vertically aligned carbon nanotubes (VACNTs) has been investigated and interpreted in the view of a collective nanotube response by taking van der Waals interactions into account. To the best of our knowledge, this is the first report on the case of collective VACNT behavior regarding van der Waals force among nanotubes as a lateral support effect during the buckling process. The local buckling propagation and development of VACNTs were experimentally observed and theoretically analyzed by employing finite element modeling with lateral support from van der Waals interactions among nanotubes.

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Graphene oxide (GO) has recently become an attractive building block for fabricating graphene-based functional materials. GO films and fibers have been prepared mainly by vacuum filtration and wet spinning. These materials exhibit relatively high Young's moduli but low toughness and a high tendency to tear or break.

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Carbon fiber-synthetic foam core sandwich composites are widely used for many structural applications due to their superior mechanical performance and low weight. Unfortunately these structures typically have very poor acoustic performance. There is increasingly growing demand in mitigating this noise issue in sandwich composite structures.

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