Shock wave experiments using a pulsed electron beam to study copper and molybdenum thermoelastic responses

Abstract

This paper presents the experimental and numerical studies of copper and molybdenum thermomechanical responses using a pulsed source of electrons (3 Mev - 3kA - 60 ns duration). These experiments permit to characterise the dynamic behaviour of materials under high pressure, high temperature and high deformation rate. The rapid deposition of energy generates shock wave motion, which commonly induces inelastic flow or failure. Several experiments have been carried out onto copper and molybdenum targets. The thermomechanical responses have been studied by registering the rear surface motion of the targets using Michelson laser interferometer or the stress history using quartz piezoelectric gage. Numerical computations of energy deposition and shock wave propagation have been performed in order to better understand the dynamics events. The computational constitutive model used for this work was previously developed for metallic material. The numerical results are in almost good accordance with experimental data. The measurement of energy deposition must be improved in order to identify the Gruneisen coefficient of materials.