Carbon nanotubes rebound bullets

Published On: March 1, 2008
carbon nanotubes are one-atom-thick sheet of graphite rolled into cylinders and held together by strong chemical bonds. Photo: American Institute of Physics.

carbon nanotubes are one-atom-thick sheet of graphite rolled into cylinders and held together by strong chemical bonds. Photo: American Institute of Physics.

Most bulletproof vests work by spreading the force of the missile, blunting its impact. Those wearing such protective gear can sustain severe bruising or blunt-force trauma to internal organs. Australian engineers at the Centre for Advanced Materials Technology at the University of Sydney hope to change this dynamic with a carbon nanotube (CNT) material that rebounds the bullet’s force.

The engineers, Liangchi Zhang and Dr. Kausala Mylvaganam, seek the optimum point of nanotube elasticity, when the tubes are fixed at both ends and when they are fixed on one end. With one end fixed, the elastic nanotubes were resilient to projectiles traveling at speeds of 200–1,400 meters per second, with most rifles firing in the 180–1,500 meters-per-second range, and most over-the-counter guns at less than 1,000 meters per second. “We’ll continue to try to understand the impact behavior of CNTs under more complicated loading conditions,” says Zhang. Read more about the research in Nanotechnology, Volume 19, Number 7, February 20, 2008.