Improved body armor on the way
By Sarah Hofius
Lightweight, flexible body armor that looks like dragon scales and is more comfortable to wear than today''s bulletproof vests could be available within two years. The armor, designed to stiffen when hit with a high-velocity projectile, also will provide increased ease of movement and more body coverage.
Today''s bulletproof vests are made from strong fibers that absorb the impact of a projectile. For added protection, ceramic plates often are inserted into the vests.
The problem with these vests, says Chuck Canterbury, president of the Fraternal Order of Police, is that they hinder movement by weighing officers down.
Body armor is effective only if it always is worn while in the line of duty; if it''s not comfortable, officers will take it off. "If officers can''t wear a vest comfortably day in and day out, then it''s not any value to us," Canterbury says.
Jack Roberts, research professor in mechanical engineering at the Applied Physics Lab at Johns Hopkins University in Baltimore, is working to create protection equal to the ceramic plate inserts.
The new armor will be made of overlapping discs embedded in plastic-like layers. Each disc is about one-eighth of an inch thick and is about the size of a penny. The discs are made of hard materials such as alumina, tough ceramics such as zirconia and metals that change their rigidity upon impact, such as iron aluminide.
These materials complement each other in strength when put side by side, says Rick Reidy, associate professor of materials sciences and engineering at the University of North Texas. When a projectile hits the vest, the discs and the polymer layers act as a shock absorber.
The armor also may be reinforced with traditional soft armor fabric, such as Kevlar.
This latest armor technology is patented, and the discs have been impact-tested. A prototype could come within two years. The group plans to submit a proposal to the Department of Defense. For the first year of production, about $200,000 is needed.
The war on terrorism makes the development of the armor particularly timely, Reidy says.
And land mines pose a major risk to the soldiers in Iraq, says Paul Biermann, material and process engineer at the Johns Hopkins Applied Physics Lab, who also is working on the armor. "Being able to extend armor over the whole body would be a real help."