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Max tensile strength of Unobtanium

  1. Sep 28, 2005 #1
    Max tensile strength of "Unobtanium"

    "Unobtanium", of course, is that ever popular fictional material used in Sci-Fi to do things that today's materials can't. The idea being that although the materials we know of and use today have well established limits, there's no telling what will be discovered "in the future", so "in the future" pretty much anything goes.

    Well, alright, that's a great conceit if your goal is a bit of "suspension of disbelief" for the sake of telling a story, but I suspect that in the real world there are in fact limits as to what any material could do, regardless of how far off into "the future" it's discovered or developed.

    For example - Space Tethers.
    If ya wanna build a big one, and I mean a really-really-REALLY big one, with hundreds of "mag-lev" cars running up and down its rails or ribbons between Earth and a ten mile diameter city three hundred miles up, that itself hangs from a plethora of rails or ribbons, from a HUGE counter weight just past G.S.O., well,.. you'd need some pretty dammed impressive "Unobtanium" to do that.

    That thought led me to this question:
    Is there a limit to the maximum tensile strength that ANY material, could ever have, regardless of how much time somebody has to come up with it?
    By that I mean that there ARE limits to the forces that hold atoms together aren't there? And if that's the case, wouldn't there be a limit to the maximum tensile strength any material could ever possibly have?

    So in that vein of thinking, what would the maximum tensile strength of "Unobtanium" be, and how would that compare to the tensile strength of something like C.N.T.'s?
    Are we talking 2%, 10%, 98%?
    Are we entering an age where we now have a pretty good idea of what "Unobtanium" looks like, at least when it comes to the limits of tensile strength?
    Or, are we no where near that far along when it comes to the kinds of tensile strengths materials could have "in the future"?
  2. jcsd
  3. Oct 22, 2005 #2
    From what I remember from engineering classes, I think covalent bonds are the strongest and thought it was calculated that the sp3-bond between carbon-carbon was the strongest, although I am not sure of that. If true, it would make diamond the material that theoretically at least has the highest tensile strength. I say theoretically because tensile strength is not just determined by the strength of the atomic bonds but also with things like crack propagation, which goes unlimited in brittle materials like glass and diamond but is stopped in ductile materials like metals.The material with the highest tensile strength so far is a material that is like diamond also carbon based and has covalent chemical bonds, carbon nanotubes.

  4. Nov 1, 2005 #3


    People such as the late Dr. Robert Forward: http://en.wikipedia.org/wiki/Robert_Forward
    and Hans Moravec: http://en.wikipedia.org/wiki/Hans_Moravec
    have talked about super strong matter based on magnetic monopoles, called monopolium. The science is sound, it's ability to be created depends on if massive magnetic monopoles exist or not. We haven't seen them yet.

    We have a pretty good idea of what "Unobtanium" based only on the Periodic Elements would look like, and that's carbon nanotubes.

    Unknown, it depends on if massive magnetic monopoles exist or not.
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