Graphene May Top Kevlar As a Bullet-Stopping Material

The Royal Society of Chemistry reports that U.S. researchers Edwin Thomas and Jae-Hwang Lee have been testing the strength of graphene mesh in one role it's probably destined to appear in down the road: as ballistic shielding material. From the article: We cannot use conventional techniques such as a gun barrel or gunpowder [on this scale],’ explains Lee. ‘Instead we used a laser to accelerate a microscale silica bullet [at the multilayer graphene target].’ The bullet was propelled into stacked graphene sheets at supersonic speeds of up to 2000mph by the gases produced by laser pulses rapidly evaporating a gold film. The team calculated the energy difference of the bullet before and after to determine the energy absorbed. Neil Bourne, director of the National Centre for Matter under Extreme Conditions in the UK, who was not involved in the research, described the technique as ‘very exciting’. ‘They have taken a standard laboratory ballistics configuration and demonstrated its utility on microscopic scales,’ he says. Graphene was able to absorb up to 0.92MJ/kg of ballistic energy in the test, with cracks forming around the impact zone. By comparison, steel targets only absorbed up to 0.08MJ/kg at the same speed.

Comments

for all this talk... where is it?

[Karmashock]

Every day I'm seeing something about how they can pump the stuff out of a damn DVD burner and how it is great at being a capacitor and all this other stuff.

And yet nothing that contains this technology.

WHY?

It is really fucking annoying to be told all these things are happening and then have no way to access any of it.

Re:for all this talk... where is it?

[Anonymous Coward]

I think the problem lies in you get media coverage on the basic research and the release of a product but no media coverage on the years of development and implementation research in order to get from A to B. It's not sexy enough for media coverage.

Re:for all this talk... where is it?

[DavenH]

There are a hundred steps in between the lab and the open market. You need a lot of funding, development and approval of patents, the approval from applicable government agencies, prototyping, mass production, marketing, and then if all that is successful, market penetration. This doesn't happen in a year. Hopefully it's highly profitable too, or its time on the market will be short-lived.

Re:for all this talk... where is it?

[pushing-robot]

And this stuff and nonsense about aeroplanes! For ten years now they've claimed breakthrough after breakthrough vis-a-vis powered flight and yet here we are in the fine year 1914 and they still have nothing to show us but more of their ramshackle prototypes! Where are the great flying ships they keep promising to take us round the world in a week's time? The bloody Hun had the good sense to invest in dirigibles; there's a technology that's going places—aha!

Re:for all this talk... where is it?

[DavenH]

You want to make something out of (name any substance)? There are only a few special cases where any government approval is required, and patents are NEVER required.

If you want any capital to operate with, you need security in the profitability of producing it. Patents are this security, and so are always necessary unless you want to throw money away. So no, you don't want to leave out steps that will quickly leave your company bankrupt. And all business sectors have codes, standards, and regulations by which you need to abide.

Re:for all this talk... where is it?

[pushing-robot]

Yes, but airplanes were no more than experiments until more than a decade after the first powered flight, when WWI spurred refinement and mass production. Graphene has also been displayed and demonstrated, but not mass produced.

2D structures like Graphene are a new class of materials, and that takes time. Plastics were discovered decades before any practical product was made. Petroleum was known for millenia before we had a clue what it was capable of. Metals too. Spend some time on Wikipedia and learn how long it took to bring any material or technology to widespread use.

Yes, I know: We live in the Internet age now, and you can become a YouTube celebrity overnight, so come on already. Alas, you can't expect science to keep pace with 21st century ADHD.

Re:for all this talk... where is it?

[Aighearach]

10 years ago they had been saying 10 years already.

We seem to have come to the root of the problem. When they say, "at least 10 years" and establish a minimum bound, you hear "10 years" and take it is a maximum.

R&D people do not promise to turn new technologies into products inside of a fixed time period. And when the say "at least 10 years" they're establishing a precision of a decade. It isn't a prediction at all, but if you wanted to translate it into one it would be something like "10-30 years" not "within 10 years."

Re:for all this talk... where is it?

[Your.Master]

Manufacturing at scale is a big problem

http://cdn.shopify.com/s/files...

The stuff is still monumentally more expensive than its competition, even with the price dropping fast, because it's new and we haven't figured out how to scale it yet. The stuff coming out of your dvd burner is not the high quality stuff, and low quality graphene is worse than non-graphene alternatives at most things.

Its use in electronics is also inhibited by the lack of bandgap, which people are looking into: http://physicsworld.com/cws/ar.... It's just another material, and pricing will dictate its use vs. less effective but still perfectly viable alternatives. While its new, this has an odd chicken-and-egg supply-and-demand relationship.

sane units - FYI

[Orgasmatron]

No one but a reporter talks about bullets in miles per hour. 2000 MPH is about 3000 feet per second.

A typical handgun bullet (9mm, 45 ACP, etc) is going to be around 1000 to 1500 fps. Shoulder arms (223, 308, 30-06, etc) tend towards the 2500-3000 fps range.

The MJ/kg figures refer to Specific kinetic energy. To convert it to foot-pounds, you need to multiply it by the mass of the projectile to find the energy in joules, then multiply by 0.73756 (or do the dimensional analysis the hard way).

Re:sane units - FYI

[pushing-robot]

A Joule is equal to one newton-meter (or metre if you're so inclined). Force times distance.

Foot-pounds are the same: Force times distance (well, distance times force). The confusion comes from pound in this case referring to "pound-force" or lbf, a unit equal to one pound times g.

J/kg is a different measure, the specific kinetic energy of an object; the amount of energy per unit mass. The imperial equivalent would be ft*lbf / lb (foot * pound-force / pound)

Metric: J/kg = N*m/kg = (kg * m/s^2 * m)/kg = m/s^2 * m = m^2/s^2

Imperial: lbf*ft/lb = lb*g*ft/lb = g*ft = ~32.174 * ft/s^2 * ft = ~32.174*ft^2/s^2

As you can see, the choice of g rather than 1 ft/s^2 was unfortunate, but otherwise the systems are equivalent.

Silica?

[Isomorphic]

One wonders how graphene fares against bullets made from graphene.

Re:Silica?

[Aighearach]

Graphene has a lot of strength in a sheet, but it is soft and floppy. A graphene bullet would just be a carbon bullet. A graphene-coated bullet would be similar to a teflon coated bullet, but not as good and a lot more expensive.

Re:insane units - FYI

[Anonymous Coward]

For sane units, 2000 mph ~= 900 m/s.

p.s. I'm an American, and I only use mph for driving speeds.

Graphene: easy to use, hard to produce

[tulcod]

Essentially, right now it is really really difficult to work with graphene on an industrial scale.

If you want to work with it in the lab, you get yourself some graphite (essentially pencil lead), some scotch tape, some solvents and you're done. It is dirt cheap and, given a good microscope and a steady hand, not too difficult to work with.

But of course this is no way to work with it on any larger scale. You want to be able to produce a certain amount of it, reliably and precisely. No flaws in the graphene crystal. No multi-layer graphene (which in fact is one of the toughest things to avoid).

This is all really difficult right now.

The situation was similar for transistors, if you recall: the first solid-state transistor was invented in 1947 (by 1956 Nobel prize winners John Bardeen, Walter Brattain and William Shockley), but it took until the 1960s for ICs to take off (Jack Kilby, 2000 Nobel prize winner, is usually pointed out as the culprit). It took until 2004 (!) for the first single-layer graphene to be isolated (by 2010 Nobel prize winners Andre Geim and Kostya Novoselov). So expect the first industrial application of graphene somewhere around the end of this decade, and some patent wars around 2019-2025, and then a Nobel prize for the inventor of whatever industrial process we will be using, around 2040.

Re:I wonder

[denzacar]

Kevlar tactical vests, being essentially a ballistic, polymer weave, have a shelf life of only about 3-5 years or so before they lose their power to slow and stop bullets.

No they don't.

They are GIVEN a shelf life of 3-5 years based on lab tests interpreted in such a way that the continuous chain of procurement of such vests by the police and the military is maintained AND so the producers of said vests could cover their asses in court in case it's needed.
"See, your honor, evidence shows that the officer Smith exposed his vest to higher temperature and UV light than what is written on the label. Ergo, it is his fault that high velocity round our client's vest wasn't ever designed for, not to say that it isn't the greatest vest out there, wasn't stopped by the said vest which is still a perfectly safe vest if you buy it brand new every 3-5 years."

Back in reality, you'd need to either soak it in strong acid or expose it to direct UV for hundreds of hours for the fibers to lose a significant part of their tensile strength i.e. bullet stopping abilities.
450 hours of direct UV will degrade 4500 denier kevlar to ~65% and 1500 denier kevlar to ~35%.
900 hours will knock it further to ~48% and ~23%, respectfully.

Even then, that only means that the TOP LAYER is degraded. Kevlar is not transparent. It degrades because it absorbs UV light.
And that's IF it was worn on top of other clothes, without any kind of a liner or protective or decorative impregnation.
I.e. If police were running around in banana-yellow ponchos for protection from bullets.

It's in the specs and real-life tests by people who are re-selling USED police kevlar vests confirm it.

It's plastic. The stuff that will take millions of years to degrade out of the ecosystem.