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Carbon NanoTubule HeatSinks

thorin

Diamond Member
http://www.eurekalert.org/releases/up-iac083000.html

"Heat energy in nanotubes is carried by sound waves; in materials that are optimal conductors of heat, these waves move very rapidly in an essentially one-dimensional direction. Drs. Fischer and Johnson found that sound waves bearing thermal energy travel straight down individual carbon nanotubes at roughly 10,000 meters per second, behavior consistent with superior thermal conductivity. But they also unexpectedly determined that even when carbon nanotubes are bundled together -- like individual filaments welded together into the giant cables that support suspension bridges -- the bonds between the individual nanotubes remain so weak that heat essentially doesn't transcend them.

"Scientists had predicted that two-dimensional or three-dimensional arrays of carbon nanotubes would permit the sound waves carrying heat to scatter in all directions, greatly reducing thermal conductivity," said Dr. Fischer, a professor of materials science and engineering in Penn's Laboratory for Research on the Structure of Matter. "Our experiments showed that even within bundles of nanotubes, sound waves remain remarkably one-dimensional."

"The sound waves don't fan out and dissipate because the bonds between nanotubes in a bundle are so weak," Dr. Johnson said. "In terms of bonding strength, you can think of nanotubes in a bundle almost like dried spaghetti sliding freely back and forth when you shake its box." "

Heh I can just see new GlobalWins coming out made of this 🙂 (in 2 or 3 years)

Thorin



 
Well it would stand to reason, as compressed carbon (diamonds) is the best conductive material known. Of course I'm not waiting for Alpha to put out the PEP66 Diamond edition 🙂
 
Yes Diamonds are ~5 times better then copper when it comes to Thermal Conductance.

However there are a few factors that make CNT better:

? Low cost (obviously)
? Weak bonding between tubes (weaker then the bonding in a diamond). Allowing greater 1 dimensional heat (sound) transfer.

Thorin
 
Carbon nanotubes are gonna cost NOTHING in 5 years time. This stuff is gonna be used in EVERYTHING. Something like 10 times the strength to weight ratio of regular carbon fibre.

Big market = cheap as you like.

Seb
 
"You expect solid blocks of carbon nanotubules to cost less than diamond?"

no I expect these to cost less then a comparable material, namely, ARTIFICIAL Diamonds.
 
Yes Diamonds are very good conductors. As are many materials. The problem lies in transfer from one material to another. I have tinkered with Diamond powder and so has another well known paste manufacturer. We both concluded that the diamond powder works well for heat tranfer but not as an interface material.
 
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