The high strain-rate behaviour of three molecular weights of polyethylene examined with a magnesium alloy split-Hopkinson pressure bar

TL;DR

This study investigates the high strain-rate behavior of polyethylene with different molecular weights using a modified split-Hopkinson pressure bar system incorporating magnesium alloy pressure bars for improved data resolution.

Contribution

It introduces a modified pressure bar system with magnesium alloy to enhance data accuracy for low-density and high-density polyethylene testing.

Findings

Magnesium alloy pressure bars increased transmitted pulse amplitude.

High-speed video confirmed the accuracy of strain gauge data.

System demonstrated long-term reliability during testing.

Abstract

A traditional split-Hopkinson pressure bar system has been modified by the addition of ZK60A magnesium alloy pressure bars in order to increase the resolution of data when examining specimens of low-density, high-density and ultra-high molecular weight polyethylene. It was found that the low density of the ZK60A allowed a decent increase in transmitted pulse amplitude, whilst its relatively high yield strength afforded long-term reliability of the system. The accuracy of data obtained from the fitted strain gauges was verified with the use of a high-speed video camera, and was found to be an excellent match.