The above block of foam is less than an inch thick. A bullet shouldn’t have any problem punching through that, right? Wrong. Meet composite metal foams, one of the materials of the future.
Metal foams are fairly commonplace in manufacturing. They’re used as chemical filters, heat exchangers, and for other industrial purposes. Composite metal foams, though, are a new type of material where hollow beads of one metal, like steel, are “bubbled” into a matrix of another metal, like aluminum. The result is a material that’s relatively light and easy to compress, but tough beyond belief. Research before the above video was shot found that composite metal foams were effective radiation shields and could easily take high-impact collisions.
The bullet, however, is a game changer. Notice that this doesn’t just stop the bullet, but pretty much completely atomizes it. Essentially, what happens is the foam doesn’t part under the bullet, while the bullet is going so fast it forces itself into the foam. The foam will deform a bit absorbing the impact, but the bullet is essentially shoving itself through a sieve. It shreds into thousands of particles, diffusing the force and scattering the bullet everywhere.
You won’t be wearing composite metal foam body armor tomorrow; they’re expensive to manufacture and this is just the beginning of tests. But one doubts the military is going to let a material like this stay in the lab for long. Pair it with some Boba Fett body armor, perhaps add a little graphene, and you’ve got the beginnings of a bona fide superhero on your hands.
(via Phys.org)