Impact behavior of shear thickening fluid treated CFRP by using SHPB technique

Abstract This work systematically studies the high strain rate impact behavior of shear thickening fluid (STF) treated carbon fiber-reinforced polymer (CFRP) composites. Two STFs were synthesized, with concentration of 15 wt% and 20 wt%, respectively. The findings shown that STF can considerably enhance the stress response and energy absorption performance of CFRP, and both exhibit obvious strain rate effects. With the rise in the concentration of STF, the peak stress and energy absorption further increase, reaching 32 % and 178 % of their maximum values, respectively. Additionally, the incorporation of 15 wt% STF significantly improved CFRP’s energy absorption efficiency, outperforming pure CFRP by factors of 1.62, 1.85, and 3.35 at various high strain rates. At a 20 wt% STF concentration, these values escalated to 2.75, 2.70, and 3.41, respectively. It is crucial to highlight that the observed enhancements are limited to high strain rate impacts. In contrast, under low strain rate conditions, STF reduces CFRP’s peak stress and energy absorption due to its lubricating effect. Consequently, CFRP-STF composites are more appropriate for environments with higher and faster impact loading, e.g. vehicle collisions and military applications.