Study on dynamic and static tensile and puncture-resistant mechanical properties of impregnated STF multi-dimensional structure Kevlar fiber reinforced composites

Shear thickening fluid (STF)-impregnated Kevlar fabric can be used as “Liquid armor” for the protection of weapons and equipment. The concentration of dispersed phase in STF and the fabric structure are important factors that affect the mechanical properties of composites. To obtain the mechanical properties of Kevlar fabric impregnated with STF, nano-sized silicon dioxide particles (SiO2) and Polyethylene glycol were used as dispersing phase and dispersing medium, respectively, by impregnating Kevlar fabrics with 2D planar and three-dimensional (3D) angular interlock structure, fiber-reinforced composite fabrics impregnated with STF with different physical structures were obtained. The results show that the shear thickening behavior of STF is the most obvious when the concentration of STF is 60%. In addition, fabric structure and STF concentration play an active role in the mechanical properties of STF/Kevlar fiber reinforced composites. Compared with pure Kevlar fabric, the maximum tensile load and the maximum puncture load of the three-dimensional angular interlocking structure of STF/Kevlar fiber reinforced composites are increased by more than 13,000 N and 120 N, respectively. The research results can provide theoretical support for the mechanical properties of STF/Kevlar fiber-reinforced composites and individual protection research.