Super-thin nanotube body armor promises to stop and deflect bullets

Posted by Humphrey Cheung

Sydney (Australia) – Bulky body armor and bullet-resistant vests could be a thing of the past, thanks to some innovative research by two Australian scientists.  Professor Liangchi Zhang and Dr. Kausala Mylvaganam from the University of Sydney say sheets of thin carbon nanotubes can stop and even deflect bullets without deformation.  Their research has been published in the Institute of Physics Nanotechnology journal and the pair claims that .6 mm thick of carbon nanotubes could stop a speeding handgun round.

You can read their research in the following PDF.  So far the pair haven’t actually tested firing a bullet at a sheet of carbon nanotubes, but they say .1 mm thick sheets of the stuff can block and deflect 62 joules of energy – in simulation.  So a low energy handgun round, with approximately 320 joules of energy, could be stopped by six layers of CNTs.

In their simulations, the professor and doctor also found that CNT are more elastic than convention ballistic fibers like Kelvar, Dyneema and Spectra – materials that have been used in bullet-resistant vests for decades.  They say this allows the nanotubes to actually deflect the bullet away from the victim.  Apparently the CNTs don’t deform after repeated hits which make them excellent candidates for “body armour and explosion-proof blankets,” according to Zhang and Mylvaganam.

Of course you can’t just wear layers of carbon nanotubes around because they have to be bound together and placed into a suitable carrier.  Modern ballistic body armor consists of layers of fabric that are weaved and glued together.  This mass of fabric is then placed into a shell with Velcro straps.  All of this adds weight and thickness to the final product.

Another problem is that 320 joules of energy is quite a low number when compared to the energy contained in high-caliber rifle and handgun rounds.  Those can pack 1500 joules and beyond.  Going by the researchers’ calculations, these bullets would require 3 mm thick worth of CNT sheets to stop – still thin, but now you’re talking about a significant amount of nanotubes required to fashion a vest.

Zhang and Mylvaganam aren’t the only ones studying CNTs for their ballistic protection properties.  Less than two weeks ago, the BBC published an article about University of Cambridge Professor Alan Windle who is working on making his own nanotube body armor.