Dynamic behavior of impact hardening elastomer: A flexible projectile material with unique rate-dependent performance

Abstract

The impact hardening effect, with mechanical properties strengthened by the impulsive loadings, is a unique phenomenon in certain polymer systems. In this work, the dynamic response of impact hardening elastomer (IHE) composite under different strain rates was studied. Due to the crosslinking interactions between the shear stiffening gel (SSG) and methyl-vinyl silicone rubber (VMQ) in the elastomer structure, the IHE overcomes the cold-flow character by improving the initial storage modulus from 593 Pa to 7260 Pa in the natural state. Besides, the IHE sphere exhibits a typical visco-elastic character under a free dopping rebounding process with a high coefficient of restitution (86.27%) and equivalent modulus (0.18 MPa). Interestingly, another transition between the rubbery and brittle state was verified both experimentally and numerically. Owing to the adjustable mechanical properties according to the different strain rates, the IHE shows a promising perspective as a new generation flexible projectile in non-lethal occasions.