1. Introduction
Safety has always been the principle concern for the human beings. Since the born of the humanity, men have looked for a way to protect themselves from animals and from other men. With the introduction of knives and guns it was necessary to invent a armor that would have fit on the bodies without hindering the movements. The first kind to be used was the metal armor. It turned out to be quite resistant against the weapons of that era. With the improving of the power of the weapons and with the invention of the gunpowder it had been necessary to work on the betterment of the self protecting devices. In 1971 with the introduction of the Kevlar, the industry of the body armors faced a big change [1]. The Kevlar is a para-aramid synthetic fiber much lighter and resistant than the steel. To be able to create a vest that can protect a body from the penetration of a bullet it is necessary to create a texture made of many layers. Because of this texture the armors results quite heavy and uncomfortable to be used, so the research teams are working to improve the ballistic performances of the material to be able to lower the number of layers. Another issues that has …show more content…
In theory the particles have extremely small inter particle gaps and it is possible that additional hydroclusters will form through aggregation [9].
A STF-impregnated Kevlar with no impact on it has a high rate of comfort and flexibility. However, the STF behaves like a rigid solid and boost the ballistic protection of body armor. STF is saturated with colloidal silica nanoparticles. When the hydrodynamic forces overcome the inter particle forces at high shear rates, hydrodynamic clusters form and shear thickening happens [10]. Consequently, this reaction improves the energy absorption of Kevlar body armor as the viscosity of the STF increases during the
Safety has always been the principle concern for the human beings. Since the born of the humanity, men have looked for a way to protect themselves from animals and from other men. With the introduction of knives and guns it was necessary to invent a armor that would have fit on the bodies without hindering the movements. The first kind to be used was the metal armor. It turned out to be quite resistant against the weapons of that era. With the improving of the power of the weapons and with the invention of the gunpowder it had been necessary to work on the betterment of the self protecting devices. In 1971 with the introduction of the Kevlar, the industry of the body armors faced a big change [1]. The Kevlar is a para-aramid synthetic fiber much lighter and resistant than the steel. To be able to create a vest that can protect a body from the penetration of a bullet it is necessary to create a texture made of many layers. Because of this texture the armors results quite heavy and uncomfortable to be used, so the research teams are working to improve the ballistic performances of the material to be able to lower the number of layers. Another issues that has …show more content…
In theory the particles have extremely small inter particle gaps and it is possible that additional hydroclusters will form through aggregation [9].
A STF-impregnated Kevlar with no impact on it has a high rate of comfort and flexibility. However, the STF behaves like a rigid solid and boost the ballistic protection of body armor. STF is saturated with colloidal silica nanoparticles. When the hydrodynamic forces overcome the inter particle forces at high shear rates, hydrodynamic clusters form and shear thickening happens [10]. Consequently, this reaction improves the energy absorption of Kevlar body armor as the viscosity of the STF increases during the