Joint research study aims to maximize strength of body armor for soldiers

A Rice University lab, in collaboration with researchers at the Massachusetts Institute of Technology's Institute for Soldier Nanotechnologies, recently conducted an experiment in an effort to create stronger, lighter materials.

In the process to find out what happens in a nanosecond by creating the nanoscale target materials and the microscale ammo, researchers gathered a surprising amount of information about how materials called block copolymers dissipate the strain of sudden impact.

The goal of researchers is to find novel ways to make materials for stronger and lighter body armor, jet engine turbine blades for aircraft and for cladding to protect spacecraft and satellites from micrometeorites and space junk, according to a Rice University news release.

The group was led by Rice materials scientist Ned Thomas and Rice research scientist and lead author Jae-Hwang Lee.

The researchers were inspired by their observations in macroscopic ballistic tests in which a complex multiblock copolymer polyurethane material showed the ability to not only stop a 9 mm bullet, but also seal the entryway behind it. To test their ideas, the team came up with a miniaturized test method, call the laser-induced projectile impact test.

The researchers deduced that a projectile hit their target 2,000 times faster than an apple falling one meter hits the ground, but with a million times less force. Because the projectile's impact area is so concentrated, however, the impact energy is more than 760 times greater.

"After the impact we can go in and cross-section the structure and see how deep the bullet got, and see what happened to these nice parallel layers," Thomas said. "They tell the story of the evolution of penetration of the projectile and help us understand what mechanisms, at the nanoscale, may be taking place in order for this to be such a great, high-performance, lightweight protection material."

Rice University is at 6100 Main Street, Houston. For more information, visit www.rice.edu.