Impact Response of Shear Thickening Fluid (STF) Treated High Strength Polymer Composites - Effect of STF Intercalation Method

Modern and sophisticated ammunition systems have necessitated the development of advanced ballistic protection personal armour systems that are damage resistant, flexible, light-weight and possess high energy absorbing/dissipating capacity. Although, exhaustive studies are available which show the improvement in impact resistance of STF-treated high performance fabrics, but there are limited studies which explore the efficacy of STF impregnation method. In this study, an attempt is made to understand this aspect. The low velocity impact studies were conducted on drop tower machine, while high velocity impact studies were accomplished on Split Hopkinson Pressure Bar (SHPB). High impact Poly Propylene Co-polymer (CO15EG) and UHMWPE variants Gold Shield® and Spectra Shield® were chosen for this study. It was observed that when STF was kept in liquid form between layers of ballistic fabrics, the composite exhibited reduced performance, whereas, when STF was impregnated in a ballistic fabric it had a synergistic effect to enhance the impact toughness of ballistic composite.