Wednesday, September 16, 2009

"NANOTECH: Nanotubes sorted, aligned to reduce friction"

As much as six percent of the gross national product is expended overcoming the effects of friction, according to the Department of Energy which plans to change all that at the nanoscale where friction is an even more pronounced effect. By assembling an international team to study the effects of friction on tiny carbon nanotubes, DoE funded researchers now claim that half as much friction will be encountered by aligning them properly. Look for carbon nanotube based electronics within five years. R.C.J.

An international team studying the effects of friction on carbon nanotubes claims that it can be cut in half when carbon nanotubes are aligned lengthwise rather than transversely. Carbon nanotubes are as small as a single nanometer in diameter, making it impossible to accurately pick-and-place them with robots. This obstacle prompted scientists and engineers to search for alternative methods for assembling nano devices. The researchers used an atomic force microscope (AFM) to characterize the coefficient of friction for carbon nanotubes with different grain orientations. The researchers concluded that higher friction in the transverse direction was the result of soft lateral distortion in the tubes' shape, which they called "hindered rolling."