New Material Harder Than Diamond

Here's something I read a few days back:
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It's about a new carbon material that's harder than diamond. It seems
to be obtained by compressing fullerene carbon at extreme pressure.
Just a few questions, if anyone cares to answer:
How is it possible for carbon material to be harder than the diamond
lattice? Isn't that lattice the ideal geometric shape for hardness
purposes?
Can one assume this new material will be comparable in brittleness to
diamond?
They briefly say that the process could be scaled up for
industrial-scale production. Will it only be possible to make this
material in bulk using the extreme pressure? When we see diamond-coated
razorblades and other diamond-coatings in consumer products, will the
manufacturing process for this new harder material allow for coating it
onto things?
Is the manufacturing process likely to be significantly more expensive
than for industrial diamond manufacturing?
Reply to
manofsan
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Hardness is not measured in GPa.
Physicists tend to ignore common engineering standards.
Michael Dahms
Reply to
Michael Dahms
The article stated, in the first line:
It is almost universal to refer to hardness as the result of indentation which involves plastic flow, or scratching which involves some form of fracture.
Hardness as "Isothermal Bulk Modulus" probably doesn't mean what you think it means.
Theoretically, you could achieve this narrow definition of hardness by somehow straightening the carbon to carbon bond load path (in allthree directions at once), and if you think about the article and what it says, you can see that the configuration they describe MAY do that.
Press releases are just press releases... That is quite important to remember.
Read the full paper, like a real scientist would, and then make up your mind.
But feel free to endlessly speculate..
All that endless speculation occurred over a decade ago with "Buckyballs", "Diamond Like coatings" and so on.
IF you remember all that wonderful hype.
snipped-for-privacy@yahoo.com wrote:
Reply to
jbuch
Well it could be and is sometimes. Heteronuclear diamond goes up to ~105 GPa. I wonder how tough ballas gets.
-Aut
Reply to
Autymn D. C.
^^^^^^^ That's not a hardness but a stiffness. Toughness is a different property as well.
Michael Dahms
Reply to
Michael Dahms
"The group created the ADNRs by compressing the carbon-60 molecules to 20 GPa, which is nearly 200 times atmospheric pressure..."
The problem with physicists is that being off by three orders of magnitude is considered acceptable. 20GPa = 197385 atm.
Reply to
brian stahl
Wrong, it's much lower than the moduli. Indentation tables are easily converted into stress tables.
-Aut
Reply to
Autymn D. C.
The are only easily convertet, if you now the conversion rule. There is no general conversion rule.
Michael Dahms
Reply to
Michael Dahms

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