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Carbon nanotube exoskeleton

  1. Jun 16, 2013 #1
    Can we make exoskeletons out of CNTs? I have a few questions
    1. Do CNTs expand when electricity is applied or you have to put wax betwen them?

    2. Can we produce enough nanotubes to make a full-body suit?

    3. Is graphene suitable for an armor? Some say that when you put a elephant on a pencil and put it on a sheet of graphene, it won't break.

    4500 kg - elephant's weight 0.001256 square meters - area of a pencil tip???
    force pulling elphant down: 4500*9.8=44 100 N

    44 100:0.001256≈35 111 465 Pa
    Last edited: Jun 16, 2013
  2. jcsd
  3. Jun 16, 2013 #2
    1. I'm not sure how to answer that.

    2. Depends on what you consider a body-suit. If you mean covering every area of the human body by a single layer of nanotubes, yes. But you would want much more than a single layer of CNTs for armor.

    3. You're misunderstanding the quote there. It's said when you balance an elephant on a pencil and put it on graphene with the thickness of Saran Wrap, the sheet would break.

    Assuming saran wrap is 10 microns thick and graphene is ~0.33 nanometers thick, you'd need ~30,000 sheets of graphene. Now there's a problem there. Graphene only has its special properties as a single layer, once you start to stack graphene, it becomes less and less special and eventually becomes graphite. So that quote would awfully hard to test, in my opinion.

    tl;dr, I don't think graphene is suitable as an armor just yet, nor do I foresee it being so in the future, but I'm not an expert in armor.
  4. Jun 17, 2013 #3
    I have a site that tells nothing about putting wax between the tubes: http://phys.org/news156781465.html Some say that the wax will make the muscle stronger.
    But why is a single nanotube stronger than a bundle of CNTs?
  5. Jul 21, 2013 #4
    For the purpose of armor, CNT based composite, I think, would be the best solution, but extremely expensive.
    But not sure it's good idea to use them for artificial muscles in exosceleton. As it said by the link you provided, 'muscle' is made of aerogel based (very rarefied) oriented nanotubes, and stretching effect observed in orthogonal direction.
  6. Aug 3, 2015 #5
    Do carbon nanotubes contract at different strengths depending on how much electrical current you use? This is a question that I really need answered. Thank you.
  7. Aug 11, 2015 #6
    I would be surprised if applying currents to carbon nanotubes caused them to change physical shape or size.
  8. Aug 12, 2015 #7
    I found out the answer to my question by asking Dr. Fadel who has a Ph.D. in nanotechnology. He said that carbon nanotubes contract/expand depending on the coefficient of thermal expansion (and you can increase this coefficient by adding more electrical current). Thank you though.
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