Influences of a wide service-environment temperature range on the ballistic performance of STF-impregnated Kevlar

Abstract

Shear thickening fluids (STFs) can effectively enhance the impact resistance of woven fabrics, and they have excellent prospects for application in soft-wall containment casings for aero-engines. Considering that the operating temperatures of an engine casing are in the range −50 °C to 100 °C, this study sought to reveal the influence of this temperature range on the impact resistance of STF-impregnated Kevlar fabric and reveal its mechanisms. The results of rheological tests showed that temperature has a dramatic influence on the rheological properties of the STF examined, especially in low-temperature environments, where the viscosity of the STF is extremely large and the critical shear rate is extremely small. Picture-frame shear tests showed that the shear performance of the fabric at high and low temperatures decreases when compared with room temperature (20 °C). Ballistic impact tests were carried out using a gas-gun system at different temperatures. The ballistic limit, energy absorption, and failure morphology of the STF-impregnated fabrics were analyzed. The ballistic performance of the fabric at both high and low temperatures deteriorated when compared with that at room temperature. At temperatures of −50 °C and 100 °C, the ballistic limit velocity decreased to about 62.6% and 84.2% of its value at 20 °C, respectively.