A gooey substance normally wouldn’t seem like it could stop a bullet, but an Air Force Academy cadet has created just that.
Cadet 1st Class Hayley Weir’s interest in bullet-stopping materials was piqued when she took a chemistry class at the academy in 2014. The class was given three materials to combine in a way that could stop a bullet.
The students were given an epoxy, Kevlar and carbon fiber — materials that would harden together to stop a bullet but that could also shatter.
That prompted Weir to come up with an alternative combination of materials that would produce the same result without shattering. The academy put her in touch with a chemistry adviser who wanted to research body armor, and he suggested a shear thickening fluid as an alternative to the epoxy that hardened when dried. The fluid, also known as a non-Newtonian fluid, changes viscosity depending on whether stress or force is applied to it.
This means the material would feel gooey until struck with something, like a bullet — then it would harden enough to stop it.
The idea to separately use shear thickening fluid, Kevlar and carbon fibers as anti-ballistic materials is not new, but they’ve never been used together.