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However, the measurements are yet another demonstration of the remarkable properties of graphene. "We knew graphene was the strongest material; this work confirms it," says Konstantin Novoselov, a fellow at the University of Manchester, who was the first to isolate two-dimensional sheets of the material.
The material's strength is particularly good news for those in the semiconductor industry who hope to make computers faster by developing microprocessors that use graphene transistors. "The main liability concerning the microprocessing industry is strain," says Julia Greer, a materials scientist at Caltech. Not only must the materials used to make transistors have good electrical properties, but they must also be able to survive the stresses of manufacturing processes and the heat generated by repeated operations. The processes used to pattern metal electrical connections onto microprocessors, for example, exert stresses that can cause chips to fail. And, says Greer, the main obstacle to making faster microprocessors is that "the heat is too much for materials to take." Based on measurements of its strength, graphene transistors could take the heat.
Graphene is the basic building block of several other three-dimensional nanostructures made up of carbon, including nanotubes and buckyballs, hollow soccer-ball-shaped molecules. "In theory, a nanotube is rolled-up graphene, so it should have the same strength," says Hone. In reality, however, most nanotubes have tiny flaws--an atom missing here or there. "When you pull on a nanotube," says Hone, it breaks at any site where there's a defect.
The mechanical strength of graphene on the nanoscale could prove useful for applications other than in transistors for microprocessors. The material could, for example, serve as a durable, mechanically operated electrical switch for communications devices including cell phones and advanced radar, says Kysar.
Although most research on nanomaterials has focused on their electrical, optical, and chemical properties, "mechanical properties control more than it might appear," says Greer. Existing databases of materials' strength don't account for differences in strength at the nanoscale. But now, at least, researchers testing the strength of nanomaterials will have a record to shoot for.
Graphene isn't a one-slice through diamond, although both are very strong carbon bonds. Graphene is one flat layer of hexagon-shaped bonds (like in a bee hive) whereas diamonds follow a tetrahedal pattern (three-cornered pyramid).
One can easier imagine why diamonds should be strong because there are no weak angles - it all consists of perfect triangles (minus impurities).
But why exactly graphene is so strong is beyond me.
Actually The strongest metal known to man is Dragonforce.
Herman Li is a god.
Look it up, you will understand... silly scientists.
Heh, Dragonforce is awesome, but Graphene is not a metal... Sorry to ruin your joke.
The article didn't mention exactly what material property was measured by the researchers, or what was meant by "strength." Yield tensile stress? Ultimate tensile stress? Elastic modulus? How about a numerical value for the quantity?
As a mono-atomic sheet, I'm guessing it's not one of the strongest materials in compression.
I'm not familiar with the exact definition of those metrics, but maybe you can determine what they mean by their analogy of a car balanced atop a pencil balanced on a sheet of graphene stretched over the opening of a coffee cup.
Given by the description, it appears they have conducted something akin to a hardness test (google it). What they are measuring is a relative metric--how much energy it takes to break the material. From this they can compare it to other known thin film materials and interpolate the strength--and other properties--of graphene. This test just gives researchers and manufacturers a ballpark for expected strength of the material. Manufacturers will probably not be making "perfect" graphene anyways.
Aside from balancing cars on pencils on top of coffee cups - what are some practical applications of this stuff?
If's it made of carbon atoms, can we use it to convert GHH's to a super strong product, and use it to sequester Co2 indefintely?
Can we make car bumpers out of it? How about beehives due to it's crystalin structure?
Just Curious
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Scratch that....I just read page two...
The researchers measured graphene's intrinsic strength and elastic properties. Those readers who want the numbers can find them in this Science paper: http://www.sciencemag.org/cgi/content/abstract/321/5887/385
If graphene is stronger than nanotubes, it can be a candidate material for space elevator tethers. Made into a hose shape, it could be used to squirt air into space at modest rates, enlarging the cooling area, so cooled air comes back down from space. So the carbon is sequestered, the space elevator makes space travel cheap, and global warming is cooled all in one project.
Wouldn't the air escaping from Earth make a farting sound and cause the planet to fly around erratically - just like toy balloons?
(Sorry - that image just got stuck in my head (I couldn't resist))
Except you. And you can't leave the room or roll the window down to escape.
Is it as strong as spiderweb silk? Now that's a well-designed material & production facility. Hopefully with lots of smart hard-working people we can match it someday.
The strongest material in the known universe are the 'PRIMS' in Second Life. A 4096 meter long prim, cannot be measurably deflected even if supporting the equivalent of a battle ship at its center. Now that! is strong!
Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
This document is part of the “How-To Guide for Most Common Measurements” centralized resource portal. This tutorial provides a detailed guide for measurement and device considerations to take temperature measurements using thermocouples. Get an introduction to thermocouples, which are inexpensive sensing devices widely used with PC-based data acquisition systems. Also review some specific thermocouple examples and learn how thermocouples work and ways to integrate them into a data acquisition measurement system.
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Guest (dib)
Graphene strength
It's just a 1-atom slice thru a diamond, yes? You'd expect it to be strong, no?
dib
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