New research published in the journal Science shows that the super-material graphene will withstand the impact of a speeding bullet better than either steel or Kevlar.
A team of scientists from Rice University in Houston, Texas, tested graphene’s strength by setting up a miniature firing range in the laboratory. For gunpowder, they used a laser to vaporize gold filaments. Bullets were micro-sized glass beads. The targeted graphene sheets were placed together to form mats that were from 10 to 100 sheets thick.
The researchers fired the tiny glass bullets at their targets at speeds as high as 6,700 miles per hour (10,780 kilometers per hour)—about one third the speed of an actual bullet. They used electron microscopy to measure how well the graphene withstood the impact.
They found that the graphene sheets performed 10 times better than steel and twice as well as Kevlar, the material now used in the manufacture of bullet-proof vests.
Graphene, which was first produced in the lab in 2003, is so thin—only a single atom thick—it is almost two-dimensional and because of its honeycomb lattice structure is 100 times stronger than steel. The new study is the first to test this amazing material for use as body armor.
The researchers found that the graphene sheets were able to dissipate a bullet’s energy by stretching and forming small cracks to absorb it. This ability, they explain, is due to the material’s extreme stiffness combined with low density, which allows energy from something traveling at bullet speed to move through it and dissipate very quickly.
If a way can be found to mass produce graphene sheets at a low enough cost and in sufficient quantity, the team says the material could well be used to make new tougher bullet-proof vests..