Dynamic mechanical characteristics of starch-based shear thickening fluids at high strain rates
Chengrui Xie, Yuliang Lin, Ke Li, Minzu Liang, Yuwu Zhang
Abstract
Shear thickening fluids (STFs) exhibit unique rheological properties, but research predominantly focuses on SiO 2 -based systems for ballistic applications, with limited studies on starch-based STFs (S-STFs) at high strain rates. This study investigates corn, potato, and mung bean S-STFs subjected to dynamic compression (1870 s −1 ∼ 8510 s −1 ) via split Hopkinson pressure bar (SHPB) testing. Results show that S-STFs exhibit mass fraction and strain rate dependent behaviors regarding peak stress, impact toughness, and transition times. As the starch mass fraction increases from 50 wt% to 60 wt%, the peak stress of corn starch-based STF rises from 96.37 MPa to 126.95 MPa, and impact toughness increases from 77.36 Jm − 3 ·10 6 to 98.72 Jm − 3 ·10 6 , while the transition time decreases from 57 μs to 26 μs. Similar trends are observed in potato starch-based and mung bean starch-based STFs. Higher strain rates lead to elevated peak stress and improved impact toughness, with reduced transition times. Mung bean starch-based STF exhibits superior shear thickening behavior due to more uniform particle size distribution and higher aspect ratio. A phenomenological model establishes quantitative relationships between particle morphology, mass fraction, and compressive response. This study provides significant insights into the behaviors of S-STFs in extreme environments.