Stronger than a speeding bullet
Providing protection against impacts from bullets and other high-speed projectiles is more than just a matter of brute strength. While traditional shields have been made of bulky materials such as steel, newer body armor made of lightweight material such as Kevlar has shown that thickness and weight are not necessary for absorbing the energy of impacts. Now, a new study by researchers at MIT and Rice University has shown that even lighter materials may be capable of doing the job just as effectively.The key is to use composites made of two or more materials whose stiffness and flexibility are structured in very specific ways — such as in alternating layers just a few nanometers thick. The research team produced miniature high-speed projectiles and measured the effects they had on the impact-absorbing material.The results of the research are reported in the journal Nature Communications, in a paper co-authored by former postdoc...