Roadside bombs have taken a heavy toll of life and limb in the wars of the last decade, underscoring the need for blast protection regardless of whether troops are on foot or in a vehicle. But a full suit of medieval armor made from ballistic ceramic is not practical for negotiating a modern battlefield, if that would work at all.
The rapid fielding of mine-resistant ambushed protected vehicles helped keep mounted troops safe by increasing the armor and raising ground clearance compared to other troop carriers. The hulking trucks have saved lives, but they are cumbersome, don’t perform well off road and guzzle gas.
With metal and ceramics, there is a direct correlation between weight and protection. The more steel or aluminum in a vehicle hull, the better protection it offers. But whether it is a vehicle or a ballistic vest, more material adds more weight and all the disadvantages that come with it.
Weighing down soldiers with personal protective gear is a particular concern. Armor must deflect bullets, blasts and shrapnel without impeding a soldier’s movement or weighing him or her down.
Technology is progressing to where polymers and plastics can provide equal or better protection than metals or materials like Kevlar at a fraction of the weight, said Shitij Chabba, global life protection director for DSM Dyneema.
“We can take existing applications and reduce the weight tremendously,” Chabba said. “If we can make it stronger and stronger, the higher-strength fiber translates into a higher ballistic performance. We can then give our customers like the Army a choice. They can either keep the same weight with very high performance or they can keep the performance at the current level and drop the weight dramatically.”
Dyneema is a proprietary ultra-high molecular weight polyethylene that can be formed into flexible cloth-like materials or compressed into hard pieces that can then be molded into nearly any shape such as helmets, conformal chest plates or vehicle door panels.
The Army’s enhanced combat helmet, which soldiers began wearing in fiscal year 2013, is made of a similar material produced by Ceradyne Inc., based in Costa Mesa, Calif.
Dyneema is at merely 40 percent of its theoretical strength, Chabba said. Every step of the process — making the polymer, stretching it into a fiber and creating protective products — is being fine tuned to increase that performance, said Christian Widdershoven, Dyneema’s vice president of marketing and sales.
“We still have a long way to go” with improving its strength, Widdershoven said. “When you look to existing materials that are now used — like steel, or aramid [synthetic fibers] like Kevlar — there’s not too much more that can be done. They have been developed for a long time.”
Aramid fibers in general are at their peak performance, Widdershoven said.
The Army this year released a request for proposals for the Soldier Protection System that will incorporate soft and hard armor into a full-body combat suit. The Army is seeking materials that reduce weight while maximizing functionality and ergonomics while providing “ballistic, blast, blunt impact, fragmentation and flame protection.”
The Army plans to award a low-rate initial production contract for SPS in fiscal year 2015.
Dyneema is following a two-path innovation strategy to provide the Army with the materials it needs. Its protective clothing is already being used in cut-resistant Reebok socks worn by ice hockey players and in blue jeans designed to protect motorcycle riders from road rash.
Those applications represent “micro-innovations” in which incrementally more protective materials are quickly applied to problems at hand, Chabba said. The company is also working on more “radical innovation” in materials science that could provide an ideal suit of armor for future soldiers, he said.
It plans to unveil in November a “game-changing, force-multiplying technology” at the Milipol 2013 defense industry conference in Paris. Widdershoven said the announcement would be related to increasing the 40-percent ballistic performance of Dyneema protective gear.
The materials have practical application in many sectors, including law enforcement, homeland security and commercial construction, as well as in ground vehicles, ship construction, body armor and aircraft, Chabba said. The crown on the new World Trade Center building in New York was placed with slings made with Dyneema.
“In aircraft, every single ounce you can reduce helps with the fuel efficiency and the agility and the mission payload,” Chabba said. “If you use polymer materials in the construction, you don’t need to add steel or ceramics. A lot of our material was supplied for IED and roadside bomb protection. There was no other material that could even deliver that level of performance.”
Still, vehicle manufacturers, metal producers and the Army are working on improving the performance of traditional materials like aluminum. While polymers can provide extra protection for combat vehicles, the Army is doubling down on improving the design and strength of metal-hulled combat vehicles. The double-V hull, which is now used on MRAPs, Bradley Fighting Vehicles and wheeled Stryker troop carriers, has saved lives from IED blasts simply by altering the shape of a vehicle’s underside.
A “V” shape directs the blast from beneath a vehicle outward and away from the passenger compartment. Nearly all the Army’s combat vehicles are either built new with V-hulls or are being retrofitted with the technology.
Alcoa, the world’s third largest producer of aluminum, has partnered with the Army Research Laboratory to begin production of single-piece aluminum hulls for ground combat vehicles that are designed to provide better IED protection than existing hulls assembled from multiple sheets of metal. The single-piece hulls also reduce weight and assembly time, and therefore cut the cost of the vehicle, Alcoa said in an October announcement.
“For decades, the Army has recognized the survivability benefits of a single-piece hull due to its thickness, size and shape for ground combat vehicles,” Enerest Chin, chief of the Army lab’s materials manufacturing technology branch, said in a prepared statement. “Our collaborative effort to develop continuous and seamless aluminum hull technology has the potential to be a game changer for how combat vehicles are designed and made to better protect our soldiers.”
Alcoa has produced much of the armor fitted to Humvees and Bradleys. The company also announced in October its newest armor plate, called the ArmX, offers more than a 20 percent improvement in strength compared with current weldable armor plates.