Measurements of High Strain Rate Properties of Materials Using an Exploding Wire Technique

Abstract

An exploding wire method is used to produce high-pressure blast-wave loading of thick polymer cylinders. The measured outer-surface hoop-strain profiles, at strain rates of about 103 s-1, agree best with prediction for values of Young's modulus which are much higher than those measured under quasistatic conditions (strain rates of about 10-3 s-1). Low density polyethylene shows a six-fold increase in modulus, high density polyethylene more than 100%, nylon 66 about 75%, and nylatron a 25% increase

Measurements of high strain rate properties of polymers using an expanding ring method

“…The mechanical behaviour of most materials is strongly dependent on strain rate [1]. For polymers, not only does the flow stress at a given strain increase with increasing strain rate, but also the Young's modulus under quasi-static conditions is appreciably lower than at high strain rate [2], Commercial equipment is available for obtaining rates of strain up to a few hundred per second, eg drop weight and pendulum apparatus (Charpy and Izod). To achieve higher strain rates research laboratory designed equipment is used, the principal type being the split-Hopkinson pressure bar (SHPB) system [3,4].…”