A New Set-Up to Investigate Plastic Deformation of Face Centered Cubic Metals in High Strain Rate Loading

This paper presents a novel set-up designed to investigate plastic deformation of a metal at high strain rates. The set-up is similar to conventional split Hopkinson pressure bar but the striker bar is eliminated and instead of it a spherical projectile, accelerated to high velocity with a two-stage light-gas gun, impacts and penetrates in a steel plate attached to the input bar. This results in propagation of plane waves in the bars and the sample. Impacts were carried out by aluminum spherical projectiles with diameter of 3.5 mm and velocity between 2 and 2.5 km/s onto front plates with thickness 10 mm and diameter of 55mm; the thickness of samples was between 3 and 7 mm. The experimental results were compared with 3D finite element simulation. Also, the effect of projectile velocity and sample thickness were investigated through experimental tests.