Simulation of high strain rate behaviour of aluminium alloy AL6061-T6 under dynamic compression loading

Abstract

Split Hopkinson Pressure Bar (SHPB) has become a frequently used technique for measuring compressive stress-strain relationship of various material and its alloys under high strain rate. In this report, a finite element simulation of a Split Hopkinson Bar is build to analyse the effect of varying specimen diameter and striker bar‟s initial velocity on the behaviour of the material.

ANSYS Workbench coupled with LS-DYNA solver is use to simulate and produce the stress strain results. Specimen made of Aluminium alloy AL6061-T6 with length 5mm and varying diameter of 5, 8 and 10mm are used in this project for simulation test. Striker bar‟s velocities of 6m/s, 12m/s 15m/s and 17m/s are varied in this project to obtain simulation results. Stress vs time, stain vs time, strain rate vs time and stress vs strain relationships are covered in this project.

In general, higher stress and strain are observed for simulation with smaller specimen diameter and higher striker bar‟s velocity. With careful selection, smaller diameters can be used successfully to achieve high strain rates.