In impact handling, liquid has a considerable number of advantages over the solid counterpart. A liquid by definition is a state of matter in which continuous shear is possible, and this makes the instantaneous pressure absorbing capacity of the liquid much more than the solid matter. So naturally, bullet proof vests containing liquid core will have better functionality than the solid ones. A Polish engineering institute Moratex Institute of Security Technology has recently unveiled such a liquid that can be used for this purpose.
The main problem associated with the liquid use in bullet proof vests is that since the fluid film can not be thicker than a few inches at the most, it cannot withstand the impact if it remains in the fluid form once the force is applied. So, the Polish engineers have come up with a liquid that hardens upon impact thus incorporating desired properties of both liquid and solid.
The fluid is a non-Newtonian fluid as it hardens with shear-force increase. Such is its remarkable properties that Moratex claims that it can withstand bullets approaching the supersonic speed (up to 450 meters per second). In a normal kevlar, this is not possible since the high speed would induce a large deflection dangerous enough to break sternum, ribs and other bones in proximity to the kevlar itself.
In a normal kevlar, this is not possible since the high speed would induce a large deflection dangerous enough to break sternum, ribs and other bones in proximity to the kevlar itself. Moratex claims that the use of fluid fully eliminates such danger.
The fluid hardens according to the force exerted on it. Larger the impact, harder the fluid will become. If the impact is a bullet, it will immediately harden and save the user. Moratex claims that the fluid-based kevlar will be ordered by security agencies and law enforcement departments in the near future.