#USArmy finds promise in durable material for future combat helmets. Learn about it here:
ADELPHI, Md. -- Army and MIT researchers advanced a unique experimental device to better test the durability of high performance and robust polymeric materials that appear to strengthen themselves under attack by rapid impact. The Army Research Laboratory's Dr. Alex Hsieh, along with Prof. Keith A. Nelson, Dr. David Veysset and Dr. Steven Kooi, from the Army's Institute for Soldier Nanotechnology at MIT, discovered that when targets made of poly(urethane urea) elastomers, or PUUs, are impacted at very high speed by micro-particles made of silica, the PUU target shows hyperelastic behavior. That is, they become extremely stiff when deformed at strain rates on the order of 108/s, which means roughly that the material of the target deforms to half of its original thickness in an extremely short time equal to one second divided by hundred millions. PUUs also bounce back after ...