One-dimensional isentropic compression measurements of multiply loaded polymethylmethacrylate

Abstract

We present direct measurements of stress, strain, and temperature in multiply shocked polymethylmethacrylate (PMMA) discs. From these measurements we determine an approximation for the main compression isentrope of PMMA in the 0–16-GPa range. The experimental technique is based on embedding the three types of gauges (stress, strain, and temperature) in a thin PMMA disc and shock it in a series of up-going reverberations. We also show that from the measured temperature and strain increments one can calculate the volume dependence of the Grueneisen parameter in the relevant compression range.