Liquid Body Armor


Verified Military
Aug 14, 2007
New technology promises "smart" armor that hardens with impact

Developed at the University of Delaware Center for Composite Materials, a revolutionary new classification of body armor is scheduled to be released- first to the prison security industry, and later to law enforcement and military community. The product is a liquid which exhibits amazing properties. A mixture of non-toxic ethelyne glycol and nano-beads of silica, the new STF (Shear Thickening Fluid) can be stirred slowly with a spoon. If, however, a sudden force is applied, such as a stabbing motion, or sudden impact, the liquid instantly hardens, arresting all motion. This new generation of armor, pioneered under the leadership of Dr. Eric Wetzel, of the Weapons and Materials Directorate at the U.S. Army Research Laboratory, was first glimpsed by the public in 2004, and is seeing the market in 2008. Armor Holdings purchased the rights to market the material, and has selected Barrday, Inc. to further develop its applications.

STF was birthed from nanotechnology, the same line of science that brought us waterproof fabrics, better tires and even modern sunscreen. The liquid retains its properties in all sorts of temperatures, which makes it useful for military personnel who may find themselves wearing the new armor in extreme environments, from snowy mountaintops, to desert heat. Because STF is a liquid, it can be applied to the surface of fabrics as a coating, and, after absorption, will bestow "armor" properties to that fabric.

STF works by forming an instant armor "shell" as soon as a high energy impact strikes it, but resumes its semi -liquid state as soon as the energy from the impact is dispersed. As a result of this behavior of the liquid, the pressure of the impact is dispersed over the entire expanse of surface area. Anyone familiar with body armor physics will attest that this is a highly desirable property. In ballistics, concentrated energy and velocity equal penetration power. By spreading that energy over the surface of the armor, penetration is dramatically reduced. The fact that the entire surface area works in concert to disperse pressure, as a sort of "armor shell", means there is also a dramatic reduction in secondary blunt force trauma which could otherwise crush ribs, or break bones.

The applications of the new liquid armor are many, and reach beyond strictly being applied to new vests. STF can be applied to other, conventional body armor, to increase the protection level. It can be used on suspicious packages, to potentially reduce the threat of explosive destruction. Because of its light weight, and semi-liquid flexibility, it promises to increase the mobility of personnel who use body armor. This concern in particular is the topic of hot debate in the US Military, where body armor solutions have been widely criticized by many for excessive weight, and lack of flexibility.

only problem I could see is once you get shot you're leaking your armor... perhaps incorporate a coagulant type medium as well into the mix so that it basically plugs its own holes.
How well it holds up in the field remains to be seen, but it looks very promising. In the forms the researchers are using to treat kevlar, I don't think leaking would be an issue.
only problem I could see is once you get shot you're leaking your armor... perhaps incorporate a coagulant type medium as well into the mix so that it basically plugs its own holes.

Just get a new vest, you exchange ceramic plates when they get hit, etc. A little messy, but you should be able to exchange "plates" quickly.

Wonder if this is applicable to vehicles, and is the lead technology for defeating EFP's.
What I am getting at is the fact that if you can actually get it to coagulate all you would have to do to refurb armor is simply ensure it's full after any engagement where the armor actually saw an impact. It'd end up saving money if that was possible, instead of having to can the whole pack.

Either that or have a repair kit like they issue with the sleep pads, and have supply be able to get the liquid and a syringe to be able to refill the armor, something.

Plus if it was self coagulating it would be more sustainable for multi-impact, unless you basically had an overlapping multibladder setup... that would mean more weight, and since this is a fluid that on its own is slightly heavier than water per equal amount, adding in silica, it might end up being a weight issue.

It's a great idea, putting it into an effective medium of utilization is going to be the fun part.
read the article again, guys.... they're basically spray-treating it to existing kevlar vests. I'm not sure exactly how it works, but basically, the kevlar absorbs the liquid, and thus takes on properties similar to the liquid. kevlar is strong in and of itself. so when bullets or knives hit it, they get stopped, due to the strength of the kevlar AND the liquid. how this is going to be implemented, i don't know, but I'm with RP... if... IF... they can get it to work, this could be a huge step. like the change from edged and blunt weapons to gunpowder.
If this is the same stuff I saw on discovery its not a liquid per say. In its initial state its a liquid that’s held between two pieces of material ( the one I saw they were making double layered utilities/BDU's) As soon as the material was hit by a bullet or shrapnel it hardened instantly, I mean before the object even penetrated the material. They even showed it on a high speed camera. At the time they were talking about using it as a way to protect soldiers from their neck down from everything except a high powered rifle round and up. I think they said the BDU's only weighed about a pound more, which isn't bad if it gives you that kind of protection.
From one of the researchers... "We would first like to put this material in a soldier's sleeves and pants, areas that aren't protected by ballistic vests but need to remain flexible. We could also use this material for bomb blankets, to cover suspicious packages or unexploded ordnance. Liquid armor could even be applied to jump boots, so that they would stiffen during impact to support Soldiers' ankles."

I've been following this stuff for a while. Waiting to see what companies license the technology and am gonna possibly invest some $.
You can see the same type of effect at home - mix up some cornstarch and water till you have the consistency of runny pancake batter. If you mix slowly, no problem, but if you take your hand and thump the top of the mix, it will feel solid. Mythbusters used this for something once, but I can't remember what.
You can see the same type of effect at home - mix up some cornstarch and water till you have the consistency of runny pancake batter.

Yes, but will it look stylish, and be comfortable yet functional in a battlefield environment?:D