日　時

２００４年６月１７日（木）１４：００―１５：００

講演題目

Mechanical Properties of Carbon-Nanotube Ceramic Matrix Composites

講演者

Professor William Curtin
Brown University, Division of Engineering

場所

東北大学大学院工学研究科　機械・知能系共同棟６階会議室（６１１室）
〒980-8579 仙台市青葉区荒巻字青葉01
仙台市内から東北大学までの経路図
東北大学大学院工学研究科の配置図

参加費

無料

要旨

The excellent mechanical properties of carbon-nanotubes are driving research into the creation of new strong, tough nanocomposite systems. Here, the evidence of toughening mechanisms operating in carbon-nanotube-reinforced ceramic composites is presented. A highly-ordered array of parallel multiwall carbon-nanotubes (CNTs) in an alumina matrix was fabricated. Nanoindentation introduced controlled cracks and the damage was examined by SEM. These nanocomposites exhibit the three hallmarks of toughening in micron-scale fiber composites: crack deflection at the CNT/matrix interface; crack bridging by CNTs; and CNT pullout on the fracture surfaces. Interface debonding and sliding can thus occur in materials with microstructures approaching the atomic scale. Furthermore, for certain geometries a new mechanism of nanotube collapse in "shear bands" occurs, rather than crack formation, suggesting that these materials can have multiaxial damage tolerance. Evidence for a novel nanotube fracture mode is also presented.

問い合せ先

〒980-8579 仙台市青葉区荒巻字青葉01
東北大学大学院工学研究科航空宇宙工学専攻
岡部　朋永