August 22, 2011
Siddhartha (Sid) Pathak, a W. M. Keck Institute for Space Studies (KISS) Postdoctoral Fellow in Material Science, has received the first prize in the NanoArt 2011 International Competition. The inspiration for Dr. Pathak's entry entitled "In-situ SEM deformation of CNT micro-pillars" is his research on nano-mechanics of carbon nanotubes. As a KISS postdoc Dr. Pathak is working with Professor Julia Greer on mechanical testing of carbon nanotubes at submicron length scales, with a particular emphasis towards space applications.
The scanning electron microscope (SEM) image shows a top-down view of a carbon-nanotube (CNT) micro-pillar after failure at ~1 GPa stress. These CNT micro-pillars were fabricated from highly dense CNT brushes, produced by high temperature vacuum decomposition of SiC single crystals, using focused ion beam micromachining. Under in-situ micro-compression experiments, these dense CNT pillars are found to exhibit higher modulus and orders of magnitude higher resistance to buckling than CNT brushes produced using other methods. The ability of these dense CNTs to dissipate energy, while withstanding such elevated loads, is highly promising for energy-absorbing applications, especially in Microelectromechanical systems (MEMS) devices.