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Science Technology

Carbon Nanotubes Harder Than Diamond 297

purduephotog writes "CDAC has announced the formation of a new form of hexagonal packed carbon similiar to diamond. Carbon nanotubes are compressed at 75 GPa and quenched. The new material is conclusively different via Raman Spectroscopy and both cracked and indented the diamond anvil used in its creation. CDAC is also known to have created via CVD the hardest diamond to date."
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Carbon Nanotubes Harder Than Diamond

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  • by BayBlade ( 749886 ) on Friday October 08, 2004 @04:55PM (#10474266) Journal
    Does it go to 11?
    • by ikkonoishi ( 674762 ) on Friday October 08, 2004 @06:08PM (#10474985) Journal
      Parent is refering to the Mohs hardness scale [csupomona.edu] in which diamond is used as the upper end of the scale at 10.

      If this is harder than diamond then either the scale will have to be scaled to make this the new 10 or this will be set as some value greater than 10 depending on its relative hardness.
      • Or this will be set as some value greater than 10 depending on its relative hardness.


        You mean like 11? As you said, the Mohs scale assigns ordinal values to make relative comparisons, not absolute ones. For a scale which makes absolute comparisons between the standard minerals see this website [galleries.com].

    • Does it go to 11?

      man that'd be crazy [fiftyfly.mine.nu]!

  • Interesting (Score:5, Funny)

    by Anonymous Coward on Friday October 08, 2004 @04:55PM (#10474271)
    I've never done a spectroscopic analysis of ramen before - I usually just ate it
    • by francisew ( 611090 ) on Friday October 08, 2004 @05:13PM (#10474472) Homepage

      I realize you are kidding... here is what Raman really is... (give or take a few details ;p)

      Spectroscopy: study of quantities of light at various wavelengths (or frequencies). Useful because matter interacts with light, so by measuring light passing through unknown matter, you figure out what its passing through.

      Raman spectroscopy, is a branch where one looks at the wavelength shift occurring as light passes through a sample. A bit like doppler radar involves a shift of frequency (although it's not a shift due to the movement of molecues, but rather due to energy differences in orbitals as they move/distort).

      The cool thing about Raman is that you just need a single wavelength of excitation, meaning you can build a spectrometer with a single laser diode. Then you filter off the laser line, and presto, the only light left will be the spectrum of interest.

      Caveats: low intensity, frequency shift is very small, you still need a monochromator. Advantages: you get information that isn't available in standard IR & UV-vis spectra, the spectra are excitation freuency independant (not entirely true), by taking advantage of resonances it's possible to get REALLY intense spectra (resonance Raman and SERS).

  • by WormholeFiend ( 674934 ) on Friday October 08, 2004 @04:55PM (#10474273)
    to spell out Chemical Vapor Deposition?

    Overuse of acronyms degrade language, you know.
  • Somehow (Score:5, Funny)

    by Timesprout ( 579035 ) on Friday October 08, 2004 @04:56PM (#10474277)
    I cant see them becoming a girls best friend though
    • Re:Somehow (Score:2, Insightful)

      by raitchison ( 734047 )
      You never know, I'm sure they are far more expensive than natural diamonds. The price tag alone would make them really appealing to some women. :-)
    • Re:Somehow (Score:4, Funny)

      by nuclear305 ( 674185 ) * on Friday October 08, 2004 @05:28PM (#10474620)
      Until they make sex toys and condoms out of this stuff...I mean, it's harder than diamond right? That's a lot to live up to...
  • by yotto ( 590067 ) on Friday October 08, 2004 @04:56PM (#10474279) Homepage
    Raman Spectroscopy

    Dude, they're always tough until you boil them for 3 minutes. This is nothing new.
  • Possible uses? (Score:5, Interesting)

    by francisew ( 611090 ) on Friday October 08, 2004 @04:56PM (#10474284) Homepage

    This might be good for new machining tools?

    I wonder what the optical properties are, and what the maximum size of these is?

    • A thin, super-hard diamond layer? Put some on my razor blades please, so I don't need to throw them away after using them only a couple of times.

      Look elsewhere - no sig to be found here.

      • Re: Possible uses? (Score:3, Interesting)

        by theguru ( 70699 )
        Have a package of razor blades cryo treated... they'll last a really long time. A friend had a crankshaft cryo treated, and the owner of the company apparently puts disposable razor blades in with small batches and gives them out to friends, and sends them to service men overseas.
      • Re: Possible uses? (Score:5, Interesting)

        by Izago909 ( 637084 ) * <.moc.liamg. .ta. .dogsiuat.> on Friday October 08, 2004 @05:29PM (#10474628)
        It cost me $15 for a pack of replacement razor blades. It cost me $30 to have them cryogenically treated. I've been using my current set for about 2 months now. The other ones got about 3-4 months of use before I threw them out. At this rate I've got about a 2 year supply left. There's a reason razor companies use the softest steel possible and charge between $5-8 dollars for a pack of 4 blades. It's also the same reason it can often be cheaper to buy a new printer instead of replacement cartridges.

        Cryogenic treating is nothing new. Top automotive racers have been freezing engine parts for over a decade now. Aeronautical companies have been doing it for longer. Did you just spend a lot of money on a special silk piece of clothing for your girl? Have it treated too. You'd be surprised how long silk will last, or how much stronger it will be after treatment. Tired of sharpening lawn mower blades? Did you buy your kid some expensive plastic toy you know he/she will destroy within a week? Damn near everything can be treated. Metals, fibers, and plastics (and other polymer compounds) are incredibly resilient afterwards.
        • Re: Possible uses? (Score:4, Insightful)

          by Baseclass ( 785652 ) on Friday October 08, 2004 @07:18PM (#10475537)
          Then why doesn't some renegade small company come out with these everlasting products and put the megacorps out of business.

          Actually forget I said that...um, I have something to take care of brb (be right back).

          • Re: Possible uses? (Score:3, Insightful)

            by Izago909 ( 637084 ) *
            Then why doesn't some renegade small company come out with these everlasting products and put the megacorps out of business.

            The same reason that every company (that I know of) which makes 100 year incandescent light bulbs goes belly up. Anyone who has toured Edison's home has probably seen the light bulbs that he made which are still in use with no modifications or reconstruction. The term "engineered lifetime" is nothing new. Any old timer should be able to tell you stories of people making the news or
    • Re:Possible uses? (Score:3, Interesting)

      by Rei ( 128717 )
      I want to know its tensile strength, so I can determine whether it'd be suitable for an economical space elevator. Impressive bulk modulus, at the very least!

      Still, 75 GPa being required to form the material is pretty high. Anyone know what type of SWNTs they used? Most, from the studies that I've seen, shouldn't need that kind of pressure. I came up with a general design previously for a press that could produce a high tensile strength fiber from CNTs, but I doubt it could handle 75 GPa.
    • Won't be efficient considering the materials to be manipulated. The basic requirement of a material to be used in machining is that it be harder than the material to be cut. Materials that are easily friable, however, tend to be quite expensive to use. The only application this material would see would be grinding, and the rate at which it would degrade would be very costly. Carbides of some type are already in use that are extremely cost efficient and capable of cutting anything that would ever see use in
  • OK great. Everytime diamonds/gems are mentioned in any way here on /. I get the familiar sound coming up from my computer room of "Honey, take a look at this. I bet NOBODY else at work would have one of these." Followed by a batting of the eyelashes and a subsequent emptying of my bank account. Please oh please stop mentioning these!!!


    Oh well, there is usually at least a sexual favor in there somewhere as well. Here's to hoping!!!
  • Am I the only one who chuckled upon seeing the file name "wang_pnas.pdf"? TGIF
  • by martensitic ( 747168 ) on Friday October 08, 2004 @05:00PM (#10474322)
    "both cracked and indented the diamond anvil used in its creation"

    And thus, the student overtakes the master.

  • by ave19 ( 149657 ) on Friday October 08, 2004 @05:04PM (#10474365)
    These are the types of advances we need to make the space elevator a reality. Either using nanotubes like this in a matrix, or more mind-boggingly, create wires of them.

    Going up!
    • Space Elevators are starting to become the new Beowulf Cluster of slashdot.

      "Imagine a space elevator made of this!"
    • Cool libertarian pipe dream!
    • by Capt'n Hector ( 650760 ) on Friday October 08, 2004 @05:35PM (#10474684)
      It doesn't really matter how hard the material is. It needs to be VERY light and be able to withstand huge tensions. For example, spider silk does well in this area, but isn't anywhere near as hard as a diamond. But then I suppose that depends on your definition of "hard"...
    • These are the types of advances we need to make the space elevator a reality.

      Yeesh. No. There are just a few other problems, as with all ideas hatched by Scifi authors (who need to do little more than make something plausible on the most abstract level. Scifi authors almost always get it WRONG- we don't all use jetpacks and atomic cars to get to work, now do we? No 'death rays'- hell, we haven't even gotten speech recognition down, really).

      I know some -other- fanboy will link to a FAQ that "answers"

      • by Artifakt ( 700173 ) on Friday October 08, 2004 @07:22PM (#10475578)
        We've got a lot of problems right here on earth, folks- and I'd much rather you all put that brainpower to them.

        There are lots of down to earth problems involving high loads and other stressors on cables. How do you make the SF bay area bridge safer against earthquakes? (or against sabotage?). How do we scale up the design of that suspension bridge to get multi-mile spans in the Florida keys or elsewhere? Is it possible to build such a bridge across the Gibraltar istmus?
        Can we make a cable that's strong and waterproof enough to safety retrofit earthenware dams all around the mouth of the Mississippi region, and do it cheaply? Is there something that could help stabilize really tall free standing radio masts in central Russia, and is thermally less expansive than steel cable, or better yet electrically non-conductive? What design changes could have kept the WTC standing for at least a few additional hours, and what sort of materials would they require?
        The thing is, if we get good answers to even some of these questions, they are likely in this case to point us towards towards space program uses as well. The problems you cite will apply to every use, not just a space elevator. Someone will be looking into using these fibers for zeppelin fabric to build really large gasbags and set up a major freight hauling system across the Mediterranian sea, and someone else will raise the issues of safety, location or insurance just like you have here.
        Half the reason so many engineers want to build really big projects like space elevators is to show all the people who toss out bullet comments just like yours for every new project, space or earth, military or peaceful, that big things can still be done. You're doing it about space. Someone else will do it about any new idea that could alleviate poverty, or clean up the environment, or somehow improve someone's quality of life. So nothing will change. Thank goodness its all perfect now.
      • For inventing the phrase "Space Fanboy" - you are now my personal hero.

        Thank you - it's about time.

        I'm as excited as any geek to have humans galavanting among the stars, but I don't feel it's going to happen, or that it even should happen, without sound economic principles. Wasting precious resources on symbolic efforts like the ISS & the space shuttle is not going to speed our return to the heavens.

        When I was young and I read all about the moon program I was so excited to think that Mars must be ri
      • I fail to see why a troll like you got modded up so far, but ok...

        Launching things into space is not relatively easy and not pretty ho-hum. In fact, the one remaining super power in this world does not even have the capability to launch people into space anymore! (the fact that efforts are under way to restore shuttle services does not change the current state of affairs)

        Energy costs _are_ a major factor, not just for the launch but throughout the entire space industry. Since launching is hideously expe

    • These guys are already on the job:

      http://www.liftport.com/carbon.php [liftport.com]
    • Heh, read Red Mars [amazon.com], where terrorists wrapped a Space Elevator twice around the planet and took out a number of settlements. That ought to be a real treat on a heavily populated planet like earth when that puppy comes down.
      • oh don't start this thread again.

        Here I'll nip it in the bud:

        Those "in the know" claim an earth-based elevator will not do that. It will be too thin to do any damage because it would fragment and burn up in the thick terran atmosphere.
    • Compressive strength != tensile strength.
    • STOP IT STOP IT STOP IT!!!

      Enough nanobot and space elevator garbage. Please! Unless we are specifically talking about science fiction. It's making me sick! When it comes to nanobots and space elevators, the abyss between available technology and implementation is larger than anything else I've ever seen. I'd be surprised if we had these things in a 100 years, let alone 10. We might as well talk about teleportation whenever a new property of light is discovered, or jacking-in whenever a new feature
      • I'm with you, fellow luddite ..and shut the fuck up about quantum computers already! IT WILL NEVER HAPPEN! the whole concept is absurd! if god wanted us to compute at quantum speeds he would have given us bigger brains! just write your goddamn shareware and shutup!
    • by Brigadier ( 12956 ) on Friday October 08, 2004 @06:07PM (#10474974)


      Keep in mind the compressive strength of a material is not the same as the strenth in tension. Not only that material like this has pretty much no elastic properties. ie, thats why you can easily shatter a diamond even though it's so strong
  • by superrcat ( 815508 ) on Friday October 08, 2004 @05:05PM (#10474378)
    Raman, the technology and dietary staple of millions of college students makes carbon nanotubes harder than diamonds, (but still not harder than the $.25 cent Raman noodles themselves)
  • the harder they come (Score:3, Interesting)

    by Doc Ruby ( 173196 ) on Friday October 08, 2004 @05:07PM (#10474397) Homepage Journal
    Now we have drills to carve parts from synthetic diamonds. Very tiny drills, for very tiny machined parts. This nanotech is starting to get good.
  • by S3D ( 745318 )
    Just to remind that every small progress in the carbon nanotubes helpful for Space Elevator [wikipedia.org] or Tether [wikipedia.org]
  • by alexo ( 9335 ) on Friday October 08, 2004 @05:22PM (#10474557) Journal
    I am still waiting for synthetic diamonds [wikipedia.org] to break De Beers [wikipedia.org]' cartel.
  • Gimme! (Score:3, Funny)

    by DiscordOfFive ( 778099 ) on Friday October 08, 2004 @05:25PM (#10474582) Journal
    Damn... Just when I get my +5 sword diamond bladed, they make a better diamond... or rather, carbon thingy
  • background (Score:5, Informative)

    by cinnamon colbert ( 732724 ) on Friday October 08, 2004 @05:27PM (#10474606) Journal
    The 2001 edition of the annual review of materials research, http://www.annualreviews.org/, has a nice review of the field of super hard materials. the authors point out that scratching a diamond is not, in intself, much evidence of anything; in the real world lots of soft scratch hard examples can be found. The authors of this article also point out that one of the few flaws of diamond is that it reacts with iron, so you can't diamond coat cutting tools; instead, you have to use much softer things like boron nitride or TiN. Nanotubes could have a major commercial future if they are harder then TiN, non reactive to iron, but softer then diamond.

    full citation SYNTHESIS AND DESIGN OF SUPERHARD MATERIALS; J Haines, JM Léger, G Bocquillon
    Annual Review of Materials Research, Vol. 31: 1-23
  • Geez, now us guys have to buy our fiancees Carbon Nanotube Engagement rings?
  • Harder than diamond? (Score:3, Informative)

    by geomon ( 78680 ) on Friday October 08, 2004 @05:45PM (#10474776) Homepage Journal
    I think the abstract said "at least comparable to cubic diamond".

    That would change Mohs hardness scale [galleries.com] if it were harder.

  • And best of all! (Score:3, Insightful)

    by forkboy ( 8644 ) on Friday October 08, 2004 @05:48PM (#10474804) Homepage
    And best of all, no African peasants had to die to make these.

  • by CrazyDuke ( 529195 ) on Friday October 08, 2004 @06:01PM (#10474935)
    ...and enough with the nanotube ring jokes. That's not what I'm talking about.

    You see, nowadays, when you want to facet a gemstone into the shapes most people have come to expect in jewelry, one has to use abrasives to put the faces in the stone. Usually Silicon Carbide grit (9.5 hardness, usually for softer stones) or diamond (10 hardness, for harder stuff) on a spinning disk to grind into the stone. But this doesn't work for all gemstones, notably diamond. Trying to facet a diamond with diamond grit on a lap (the disk) will just cut gouges into your lap. They are not cheap.

    So diamonds still have to be done the hard way: roughly shaping the stone by cleaving, then using 2 diamonds, one of poor quality, to rub the faces into the good diamond. If this stuff can be synthesized in different grits (particle sizes) for fairly cheap, then it can be used to facet diamonds with machinery rather than by hand. Much of a diamonds (and most other stones) value is actually from the labor put into faceting it. This is especially so for smaller stones. How cheap? Well, currently lapidaries are paying for synthetic diamond grit...

  • cheap space launches (Score:5, Interesting)

    by WillWare ( 11935 ) on Friday October 08, 2004 @06:06PM (#10474966) Homepage Journal
    One person commented that this may help advance the Space Elevator, and that may be true, but it's an even bigger help for the space railway because the material is good under compression (the SE needs something good under tension). The space elevator subjects its payload to about a week of heavy radiation [wikipedia.org], so it's not practical for passengers. There are still lots of non-alive things we want to put in space cheaply, and for those it's great.

    For humans, J. Storrs-Hall (of sci.nanotech fame) proposed a space railway [imm.org] that could be built sooner and more cheaply than a space elevator. It's a linear induction motor laid along a 300km-long track, 100km above the ground, where the atmosphere is thin enough to take a few orbits to decay your orbit. You drive your spaceship up a ramp to one end, and the motor accelerates you along the railway at about 10G for about 90 seconds, putting you in a slightly elliptical orbit with an apogee on the other side of the Earth. When you hit apogee, you do a burn to get into a higher orbit.

    Relatively little radiation because you cross the Van Allen belts much faster. You get to LEO without burning any of your own fuel, which is a big energy win. The railway is low enough that orbits still decay slowly, so there's no space junk to worry about at that altitude.

    The structure is a collection of A-frames, built like a radio tower. Like the space elevator, only a tiny fraction of the height is subjected to significant weather. The structure is under compression, not tension, which widens the choice of materials. According to Storrs-Hall, existing synthetic diamond [wikipedia.org] would be suitable.

    • by mlyle ( 148697 )
      Relatively little radiation because you cross the Van Allen belts much faster. You get to LEO without burning any of your own fuel, which is a big energy win. The railway is low enough that orbits still decay slowly, so there's no space junk to worry about at that altitude.

      Um, what? LEO is generally considered to be below 500km or so; the inner Van Allen belts start at 650km. Exactly what problem are you trying to solve?

      I agree that for interplanetary stuff you may want something faster than the space
      • for LEO you don't exactly get close to the Van Allen belts [wikipedia.org]. Please elaborate.

        When you ascend the space elevator, you go 200 MPH and you spend about a week getting to GEO. If you're at LEO, you've got a horizontal velocity component of about 90,000 times that much. When you do the burn at apogee, you can do a big enough burn to cross the Van Allen belts in a half-orbit. The Apollo astronauts crossed the belts in a few hours, getting about 1% of a lethal dose. Presumably the same should be possible when la

    • Uh what? Sounds good when you say it like that, but how exactly are you gonna build this "railway" at 100km up? For reference, 100km is the height that X-Prize competitors had to attain, and the world's tallest freestanding structure [wikipedia.org] is only 553m tall. You want to build something 200x higher than anything we've built before, higher than most (all but 4) planes can fly, and expect people to take you seriously? The space elevator is pretty far-fetched, the only reason people are taking it seriously at all is
  • by dakara ( 798841 ) on Friday October 08, 2004 @06:13PM (#10475029)
    Raman Spectroscopy

    I'm expecting 2 more dupes of this article.

  • I see alot of people talking about uses of these nanotubes in a space elevator, but honestly, this can't be the only application. I was thinking another application could possibly be drill bits. If we can make these nanotubes more cost effective then actual industrial grade diamond we could use them as pieces of drill bits, I think :)

    I am a student, so I don't know much about this, but surely there have to be applications for super strong materials etc.

  • Is it currently possible to calculate the hardness of a material knowing only its molecular structure? I'm guessing it is, but I don't know.

    If so, do we already know what the hardest *possible* material would be? (Assuming regular atoms, not neutronium.)

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