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New Material Harder Than Diamond
Posted by
ScuttleMonkey
on Tue Aug 30, 2005 01:32 AM
from the thats-one-gem-thats-hard-to-imagine dept.
from the thats-one-gem-thats-hard-to-imagine dept.
h4x0r-3l337 writes "Diamond is no longer the hardest substance known to man. Scientists have created a new material, called "aggregated diamond nanorods" by compressing carbon-60 under high heat. From the article: 'The hardness of a material is measured by its isothermal bulk modulus. Aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), compared with 442 GPa for conventional diamond.'"
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I want... (Score:5, Funny)
TERRORIST! (Score:5, Funny)
You TERRORIST! Won't anyone please think of the children?
Parent
Ring (Score:5, Funny)
Re:Ring (Score:5, Funny)
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Re:Ring (Score:5, Funny)
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Article Text (Score:4, Informative)
26 August 2005
Physicists in Germany have created a material that is harder than diamond. Natalia Dubrovinskaia and colleagues at the University of Bayreuth made the new material by subjecting carbon-60 molecules to immense pressures. The new form of carbon, which is known as aggregated diamond nanorods, is expected to have many industrial applications (App. Phys. Lett. 87 083106).
The hardness of a material is measured by its isothermal bulk modulus. Aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), compared with 442 GPa for conventional diamond. Dubrovinskaia and two of her co-workers - Leonid Dubrovinky and Falko Langenhorst - have patented the process used to make the new material.
Diamond derives its hardness from the fact that each carbon atom is connected to four other atoms by strong covalent bonds. The new material is different in that it is made of tiny interlocking diamond rods. Each rod is a crystal that has a diameter of between 5 and 20 nanometres and a length of about 1 micron.
The group created the ADNRs by compressing the carbon-60 molecules to 20 GPa, which is nearly 200 times atmospheric pressure, while simultaneously heating to 2500 Kelvin. "The synthesis was possible due to a unique 5000-tonne multianvil press at Bayerisches Geoinstitut in Bayreuth that is capable of reaching pressures of 25 GPa and temperatures of 2700 K at the same time," Dubrovinskaia told PhysicsWeb.
The Bayreuth team measured the properties of the samples with a diamond anvil cell at the European Synchrotron Radiation Facility at Grenoble in France. These measurements indicated that ADNRs are about 0.3% denser than diamond, and that the new material has the lowest compressibility of any known material.
In addition to working out why the new material is so hard, the Bayreuth team also hope to exploit its industrial potential. "We have developed a concept for innovative technology to produce the novel material in industrial-scale quantities and now we are looking for partners in order to realize our ideas," said Dubrovinskaia.
Low-pressure construction? (Score:5, Informative)
The group created the ADNRs by compressing the carbon-60 molecules to 20 GPa, which is nearly 200 times atmospheric pressure
200 atmospheres? That's not much pressure. SCUBA divers regularly put more pressure than that in tanks they wear strapped to their backs.
According to the "units" program on my laptop, 20 GPa is 197,384.65 atmospheres. 200 *thousand* atomospheres... that makes more sense.
Parent
General Products? (Score:5, Funny)
--
BMO - Imagine a Beowulf Cluster of Kzinti
Borazon (Score:5, Informative)
Of course, the thermodynamic process to achieve it was far expensive. Required very high pressure and temperatures.
Re:Borazon (Score:5, Informative)
I wish it was. It would make my job a whole lot easier.
However, it *is* better for grinding ferrous materials than diamond.
--
BMO - Toolmaker
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Possible uses? (Score:5, Interesting)
Re:Possible uses? (Score:5, Interesting)
Uhm, don't underestimate the profit-increasing abilities of new materials.
Borazon, for example, is a synthetic material that is used in abrasives and cutting tools. The value isn't in the material itself, but in what one can do with it.
If it's about as expensive as synthetic diamond (an oxymoron - synthetic diamond is just as real as "real" diamonds) or borazon, expect this to wind up in concrete saws, grinding wheels, end mills, drills (masonry, metal, oil industry) and a whole zoo of tools.
It's not a "modest improvement". It's a technological leap comparable to synthesizing diamonds and superabrasives, which revolutionized a lot of industries.
--
BMO
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Re:Possible uses? (Score:5, Interesting)
In some googling on this, I've become confused. "ultrahard fullerene" [google.ca] is C-60 buckyballs compressed at high temperature also. I see many different values quoted for UHF hardness and diamond. This Russian paper [aip.org] gives a value of 1 TPa in 1988!
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Re:Possible uses? (Score:5, Funny)
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Why are you giving us the modulus? (Score:5, Insightful)
How about giving us figures for hardness? Like the Brinell Hardness Number or the results of the Rockwell hardness test?
Re:Why are you giving us the modulus? (Score:5, Informative)
The hardest scale on the Rockwell test (I'll let someone else give a link somewhere) uses a diamond to make an indent. This works for pretty much everything since diamond is the hardest material.
Until now, at least. Since diamond isn't harder than this, it wouldn't make an indent. No indent, no Rockwell reading.
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Discovery? No way. (Score:5, Funny)
Re:Discovery? No way. (Score:5, Funny)
Wow, I didn't know Comic Book Guy lurked on Slashdot.....
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Re:Discovery? No way. (Score:5, Funny)
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What is it about carbon? (Score:5, Interesting)
Carbon is also the basis for buckyballs, nanotubes, and recently, nanofabric.
What is it about carbon that's so special? Can these things be done with other elements, like nitrogen? Is it just because we have an oil (carbon) based economy, or what?
Seems like all the interesting stuff in materials physics in early 2000's is ALL CARBON!
Re:What is it about carbon? (Score:5, Interesting)
Not only is it able to chain, and thereby make organic compounds, DNA, nanofiber, but the bonds it forms can be very weak or strong. So yeah, carbon has unique chemical properties, its cheap, and (too) widely available.
As a side question, who thinks that as all of the advanced carbon materials become readily available over the next 50 years, and demand increases, that we may have found our solution to global warming? We'll scrub CO2 from the atmosphere to build our carbon products!
Parent
We already do that. (Score:5, Funny)
We've been doing that for years. It's called "carpentry" and it uses these cool bio-tech machines called "trees" to convert atomospheric carbon and water into complex hydrocarbon structures known as "wood".
You have to have a source of trace minerals (typically through a "ground" or "earth" connection) but the majority of the created structures are built from atmospheric carbon and hydrogen from water. The created material is incredibly useful and can be formed with little effort using commonly available tools.
Oh, and the best part is, the process is entirely solar-powered. There's a little reverse carbon leakage when solar energy is not available (a condition we call "night") but it's negligible.
Sorry, I couldn't help myself.
Parent
Re:What is it about carbon? (Score:5, Informative)
Carbon is the only element that has these properties (valence 4, high electronegativity) that allow it to form the structures it does. Under extreme pressure and temperature, it's believed that silicon could be coaxed into some kind of polymerization. I remember reading once that a research group managed to polymerize pure nitrogen under megabars of pressure and thousands of degrees F. The result had 3 times the energy density of TNT, and violently decomposed when the pressure was let off - can anyone elaborate or corroborate?
Anyway, hope this helps!
Parent
Error in article? (Score:5, Informative)
One Use (Score:5, Funny)
I'm sure there's gold in the center of it!
So on the Moh's scale of hardness... (Score:5, Funny)
Re:Does that mean.. (Score:5, Insightful)
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Re:Does that mean.. (Score:5, Insightful)
That being said, synthetic diamonds have been on the market for a while now. In fact, my sister just bought a ring with one in it.
Parent
Not the same comparison. (Score:5, Informative)
A gross distortion — about oil. You are basically right about diamonds. While he may overhype matters somewhat, Epstein's classic book [edwardjayepstein.com] documents how the diamond cartel has been ruthless in its limit of supply to a value-sustaining level of marketing-created demand. If supply were to float free, diamonds would drop sharply in price. Furthermore, their intrinsic value within the economy isn't that high-- industrial use mainly. If the US government banned the sale of diamonds for non-industrial uses, DeBeers (and a chunk of the jewelry industry) would collapse, but the overall economy would be OK. Banning the industrial uses would hurt more, and probably trigger a recession, but not a total economic collapse.
Oil, on the other hand, has many uses -- fuel, plastics, fertilizers, and chemical feedstocks probably heading the list. Furthermore, in economic terms, there are NO elasticly substitutable replacements for it, and an exponentially growing demand as China and India become fully industrialized. Since conventional biodiesel relies on petroleum fertilizers and machinery, the "best" elastic replacement is sythetic petroleum from coal, probably becoming competitive in the $120/bbl to $200/bbl range. In the good (?!?) news, this means base (untaxed) gas prices can't do much more than triple from current levels, so we shouldn't go over $10/gallon for gasoline for about 30 years after peak oil (given the vast US coal reserves). The bad news is that the ecologic impacts are higher... which might require higher gas taxes to deal with the impact.
In addition, OPEC (and other cartel) quotas are not the primary limit on supply at this point — although they may be getting rich off it for the moment. Supply today is mainly limited the finite known reserves (with new discoveries having peaked pre-1970), and by current production rate limits (which is why a hurricane in the Gulf caused a price spike of oil to over $70/bbl). OPEC is pretty much pumping as hard as it can now.
Diamond prices are indeed deeply controlled by deliberate supply controls, and there have been times when oil prices were influenced that way, but right now, the price of oil is pure unrestricted supply and demand... where supply is running out.
(Why, yes, I am one of those "Peak Oil" kooks. Pleased ta meetcha.)
Parent
Re:Does that mean.. (Score:5, Insightful)
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Re:Does that mean.. (Score:5, Informative)
You were OK, sortof. It's not the GE process, but something entirely new (relatively).
Diamond coatings are done through a process called Vapor Deposition. It's a low pressure process, done at Standard Pressure, using a hot carbon rich gas, a reducing atmosphere, and a cold substrate (the thing you're coating).
It's an entirely new process, discovered entirely by accident by someone trying to figure out why certain welds were a bitch to grind smooth. It turned out that there were microscopic diamonds in the welds, and that was why.
--
BMO
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Some clarifications on materials and methods (Score:5, Informative)
Most (if not all) of the diamond in diamond coated drills are produced through this process.
There are several processes for putting diamond onto the lap/saw/drill. Some diamonds (natural or synthetic) are brazed onto the material, many saws and diamond wheels actually have diamond impregnated metal so as it wears, cutting action is not degraded and the cheapest method is really close to gluing the damn things to the material. In this instance, it is almost always synthetic. In gem faceting, diamond powder is actually sprinkled onto a lap and rolled into it or used as a slurry.
But as far as "most" goes, "most" diamond tools are not diamond at all but silicon carbide. And even then, it depends on the application for the lap, drill or saw. Depending on the material you are cutting or polishing, natural diamond is preferred to synthetic. This is the case when polishing diamonds and sapphires.
Also, there are a number of "fake" diamonds in the market already, none of which have had any impact on the diamond as a gem. The most common are CZ (cubic zirconia) and Moissanite which is a compressed carbon, also known as silicon carbide, and naturally occurring in meteorites but made for the market in labs. Other "brands" of fake diamonds are usually Moissanite. In diamond testing, cz fails thermal tests, Moissanite passes but fails on conductivity.
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Re:Diamonds =/= Diamonds? (Score:5, Insightful)
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Re:Diamonds =/= Diamonds? (Score:5, Informative)
Clearly, they are the same.
I often try to pick up girls by handing them large chunks of coal since it's a diamond, but in a different state. For some reason, they don't seem to go for it. Odd.
Strangely enough, no one will eat my burgers cooked over graphite (and quite frankly, graphite fires are a bit difficult to keep lit).
Carbon is one of the most versitile elements on the planet either alone or combined with other elements. Its quite worthwhile to consider a different state of it a completely different thing.
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Re:Diamonds =/= Diamonds? (Score:5, Funny)
butter and ice cream are both essentially different forms of milk, but you don't see people walking around with cones full of butter do you?
If you do, that's pretty gross.
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Re:hmmm (Score:5, Informative)
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Re:hmmm (Score:5, Funny)
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Re:hmmm (Score:5, Informative)
The group created the ADNRs by compressing the carbon-60 molecules to 20 GPa, which is nearly 200 times atmospheric pressure, while simultaneously heating to 2500 Kelvin. "The synthesis was possible due to a unique 5000-tonne multianvil press at Bayerisches Geoinstitut in Bayreuth that is capable of reaching pressures of 25 GPa and temperatures of 2700 K at the same time," Dubrovinskaia told PhysicsWeb.
I was reading that and I thought, 200 atmospheres? What do they need the 5000 ton multianvil press for? They messed it up. 20 GPa is 200000 atmospheres, not 200. [google.com]
Parent
Re:hmmm (Score:5, Funny)
program gigapascal(output);
procedure WriteResponseHeader;
begin
writeln('content-type: text/html');
writeln
end;
begin
WriteResponseHeader;
writeln('[HTML]');
writeln('[HEAD]');
writeln('[TITLE]GigaPascal[/TITLE>');
writeln('[/HEAD]');
writeln('[BODY]');
giga
while [ i [less than] 1000000000 ] DO:
giga
writeln('[BIG] This is a Gigapascal! How the hell are you? [/BIG]');
endfor;
writeln('[/BODY]');
writeln('[/HTML]')
end.
[edit requires to get slashdot to accept this]
Any questions?
Parent
Re:hmmm (Score:5, Funny)
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No good instructional computer languages (Score:5, Insightful)
It's too bad; Pascal was a good choice for an instructional language. Straightforward syntax and usable for real-world problems.
I think that the move to Java for introductory programming classes is very depressing. What people wanted was a "safe C", so that beginners didn't have to worry about bizarre misbehavior in their programs. Java, however, is a horrible choice for a teaching language, as it brings an entire raft of crap along with it, including all the OO crap, masses of library code, fat abstraction layers, and so forth. I've seen people take intro programming classes in Java and come out with some vague memories of some Java terminology, but not having learned anything about algorithms or structured thinking because they're busy struggling with all of the nonsense in Java.
The older I get, the more I think that Knuth is right about wanting CS classes to be taught in assembly.
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Re:hmmm (Score:5, Informative)
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Re:Space Lift? (Score:5, Informative)
You'd probably still use carbon, but nanotubes rather than nanorods.
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Re:To all the posters making jokes about thier wiv (Score:5, Funny)
What -- you mean there's some other kind?
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Re:To all the posters making jokes about thier wiv (Score:5, Funny)
What -- you mean there's some other kind?
I think the AC was suggesting that people should broaden their horizons. [wikipedia.org]
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Re:To all the posters making jokes about thier wiv (Score:5, Funny)
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Re:Er, what? (Score:5, Informative)
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Re:Sabotage (Score:5, Funny)
a) your friends aren't rich
b) you can scratch up the rings with normal sandpaper
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Re:Stability? (Score:5, Informative)
Eventually, they convert to graphite.
Granted, this will take a (long) while, but it's really more accurate to say graphite is forever.
I don't know about the structure of the ADNR, but it might be even more prone to conversion or sublimation than diamond.
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Re:Stability? (Score:5, Funny)
But actually, nobody would remember that, cause it's stupid.
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