Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Carbon Nanotubes

  1. Nov 23, 2003 #1
    I dunno if this is in the right forum but it seemed to fit quite nicely in here :P

    I was wondering about cxarbon nanotubes. There said to be really very strong, but what i dont underdtand is why? There so very thin! Doesd nanotechnology behave differasntly to microtechnology due to the huge size decreease? is this more of quantum mechanics than classial mechanics?

    if anybody could put meright on any of this id be very grateful :) tar!
  2. jcsd
  3. Nov 24, 2003 #2


    User Avatar

    Staff: Mentor

    When a scientist or engineer says something is "strong" they don't usually mean in an absolute sense, they mean strength to weight ratio or sometimes strenght to cross sectional area. For example, it is often said that for cables of the same thickness, a cable made of spider web material is stronger than a cable made of iron. And titanium in general is stronger and lighter than steel.

    Carbon nanotubes have the highest strength to weight ratio of any material known (afaik) as a consequence of the chemical bonding properties of carbon. For years, various other carbon materials have been used in place of metal for a variety of applications (my golf clubs) due to their high strenght to weight ratio.
  4. Nov 25, 2003 #3
    oh i see, so when they say they use it in practical applications, they actually mean a whole load of carbon nanotubes all wrapped around one another!

    thanks :)
  5. Mar 17, 2004 #4
    if you've ever looked closely at normal break cable, its 3 strands wrapped around each other, and each 1 of those strands is made from 3 smaller strands.

    and by strenth, they mean tensile strenth. as in, spiders silk has a higher tensile strenth than steal, BUT, you cant make a wall out of spiders silk, it'll just flop into a pile, like yarn.

    wether carbon nanotubes will be strong in the spiders silk sence, or steel sence, i do not know.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook