SSC-Natick Press Release
U.S. Army Soldier Systems Center-Natick
Public Affairs Office
Natick, MA 01760-5012
Contact: Chief, Public Affairs Office
Date: December 1, 2003
New fibers could lighten body armor
NATICK, Mass. -- Two new fibers are vying to one day replace the respected but heavier Kevlar, the staple of body armor for decades, as the Army strives to enhance mobility by reducing the soldier load.
Body armor is one of the more riveting individual equipment successes, especially from the ongoing conflicts in Afghanistan and Iraq, with reports of dozens of saved lives directly attributed to the bullet and shrapnel-halting ability of the helmet, flexible vest and rigid chest plate combination worn by troops.
Even though it protects well, body armor ranks with water, ammunition and weapon as the heaviest items worn or carried by troops, according to engineers on the Ballistics Technology Team at the U.S. Army Soldier Systems Center in Natick, Mass.
"The Army is putting the best available armor materials into soldiers' armor," said Philip Cunniff, a research mechanical engineer. "Part of our work in the Ballistics Technology Team is to develop new materials and techniques to lighten the load of those armor systems."
Body armor technology has advanced in the past century to protect the head and torso against high-velocity handgun bullets and fragmenting munitions, such as those from artillery shells, mortar shells, mines and grenades. Lightweight small arms protection is also now available for the torso.
The nylon "flak" vest for ground troops and steel helmet from the 1960s were replaced by Kevlar vests and helmets during the 1980s in a product called Personnel Armor System, Ground Troops (PASGT). At the users' request, performance increased with the PASGT system but weight remained about the same, according to Cunniff.
The next major change was in the 1990s with an improved version of Kevlar that helped lighten the vest by 25 percent and increased ballistic protection.
The team's objective is to reduce the weight again, this time by 25-30 percent, without losing performance. Zylon and M5 fibers show potential in meeting or exceeding that goal.
Zylon, a commercially-available fiber first developed by the Air Force in the 1980s and now produced in Japan, turned in a solid performance in testing, said Cunniff. A prototype helmet made last year with Zylon was developed as part of the Human Systems Defense Technology Objective for Ballistic Protection for Improved Survivability. The Zylon helmet weighs 1.79 pounds vs. 3 pounds for the PASGT at the same protection levels.
Cunniff said two possible roadblocks with Zylon are environmental degradation and the law requiring certain military products to be manufactured in the United States with domestic materials. Zylon has shown to break down with exposure to light, high heat and humidity, although Cunniff said there may be solutions to these problems.
An alternative material to Zylon is M5, an ultra-high performance fiber developed by Magellan Systems International in Bethesda, Md.
According to a mathematical model of Cunniff's for the estimation of impact performance based on the mechanical properties of armor materials, M5 appeared to provide exceptional impact performance.
His model indicated that M5 could cut weight by at least 35 percent compared to currently available fragmentation armor at the same protection level. So far, the ballistic impact test results with a limited, relatively low-strength sample of M5 are glowing.
"We shot it, and it came out better than we expected," Cunniff said. "We found there was something wrong with the model; we underpredicted the performance of the material. Of everything we looked at, it looks like (M5) will be a really big improvement in reducing the weight of armor."
Another feature of M5 fiber is excellent thermal and flame protection. Besides helmets, fragmentation vests and composites for use in conjunction with ceramic materials for small arms protective plates, M5 fiber could also be used for structural composites for vehicles and aircraft.
"The military market for ballistic material is cyclic," Cunniff said. "The beauty of this fiber is that it should have a lot of other markets when Army demand falls. We're hoping it becomes cost-competitive to Kevlar."
The plan is to acquire sufficient quantities of M5 fiber by next fall to make a prototype helmet, vest and small arms protective plate.
"Then we can find out how well high-strength M5 performs and find out what kind of armor we can develop for Objective Force Warrior and the Army," Cunniff said.
For more information on the Soldier Systems Center, please visit our website at www.natick.army.mil.