Can Liquid Armor Be Harder Than Steel?

One of the most important tasks given to our military commanders, as well as our military tech engineers, is ensuring that the men and women we send into harm’s way stay as protected as possible from hostile and friendly fire alike.

This function is a key design element of the vehicles our soldiers drive and fly into battle.

But when it comes to the foot soldier, the last line of defense is personal body armor.

Use of personal armor goes back thousands of years — some of the first examples of metallic plating date back to as early as the 15th century BCE.

Since then, everything from leather to paper has been employed to fulfill the basic function of stopping projectiles and edged weapons from penetrating the body.

It is a problem that has changed little in the intervening millennia. Today’s soldiers must still contend with flying projectiles — albeit at far greater velocities.

A revolution of modern materials design changed the game with the advent of Kevlar in 1965.

Synthetics Changed Everything

Using multiple layers of poly-paraphenylene terephthalamide fiber — dubbed Kevlar by DuPont — relatively light vests could be manufactured for use by police, security, and military personnel

Although not impervious to everything found on the battlefield or the street, Kevlar vests did prove effective in stopping small-caliber projectiles such as the world’s most popular police/military pistol cartridge — the 9mm parabellum — as well as shrapnel produced by most hand grenade-sized munitions.

Kevlar vests vastly improved the wearer’s survivability, while adding minimal extra weight.

In the modern battlefield, however, the dangers can far exceed the power of a 9mm bullet. For maximum protection against larger, faster-moving, rifle-sized projectiles, soldiers had to revert to rigid, heavy ceramic and steel armor plating — which causes obvious problems in limiting mobility.

Now, however, another Kevlar-magnitude revolution in personal armor is underway, and the technological basis for it comes from a surprising substance…

Can Liquid Be Stronger Than Steel?

Being tested right now by the U.S. Army Research Laboratory is a material called “shear thickening fluid” (STF).

STF is composed of hard particles suspended within a liquid matrix.

The matrix, which consists of polyethylene glycol, is non-toxic and extremely tolerant to varying temperatures.

Hard, nano-sized silica particles are the functional component of STF.

And combining the two results in a material that has some very unusual properties…

In normal conditions, the STF is highly viscous and flows like a liquid.

But the moment a rapidly moving projectile strikes, the STF particles align on a molecular level, instantly transforming the compound into a rigid material that decelerates the ballistic object and distributes its energy across a large surface area.

Stewart Penney, Head of Business Development for Design and Materials Technologies for defense contractor BAE Systems (LSE: BA), explained it further:

“The technology is best explained by the example of stirring water with a spoon. In water you feel little resistance to the spoon, whereas with ‘liquid armour’, you would feel significant resistance as the elements in the fluid lock together. The faster you stir, the harder it gets, so when a projectile impacts the material at speed, it hardens very quickly and absorbs the impact energy.”

Kevlar combined with this liquid/solid cocktail can produce body armor that is 45% thinner without any loss of effectiveness.

Battlefield Caliber Protection

Armor using STF technology has proven to be able to stop projectiles far more powerful than a 9mm round.

In fact, it’s been shown to be effective against an AK 47’s 7.62mm projectile, which travels at more than twice the velocity of a 9mm bullet and delivers between three and five times the impact energy over far greater distances.

But perhaps the best advantage this super-flexible material brings to today’s soldier is its versatility.

While Kevlar is too rigid to apply to most parts of the body, STF armor can be sown into boots, sleeves, and just about any other part of a soldier’s fatigues, allowing for unprecedented coverage alongside retained mobility.

This still-experimental technology is being pioneered right now by British Defense firm BAE Systems (LSE: BA).

Of course, there is certainly going to be a cost premium associated with this technology in the early stages of its development cycle, but, as with every other high-tech material, the first thing that will happen after initial adoption will be a gradual price decline.

A decade from now, we could be seeing STF armor on our own domestic civilian police officers — with a host of other applications waiting to be exploited.

To your wealth,

Brian Hicks

Brian is a founding member and President of Angel Publishing and investment director for the income and dividend newsletter The Wealth Advisory. He writes about general investment strategies for Tech Investing Daily, Wealth Daily and Energy & Capital. Known as the “original bull on America,” Brian is also the author of the 2008 book, Profit from the Peak: The End of Oil and the Greatest Investment Event of the Century. In addition to writing about the economy, investments and politics, Brian is also a frequent guest on CNBC, Bloomberg, Fox and countless radio shows. For more on Brian, take a look at his editor’s page.