Experiments on the hypervelocity penetration of thin aluminium sheets

Penetration experiments were conducted at the plasma accelerator test facility of the LRT/TUM. Thin aluminium sheets (8 to 125 μm thick) were impacted and penetrated by glass spheres with diameters of 20 to 60 μm at velocities between 10 and 15 km/s. In earlier experiments similar impacts on semi-infinite targets were analyzed and a method was developed to quantitatively measure the electrical charge contained in the impact plasma. This method has been extended to impacts on thin targets which were perforated. The electrical charges were measured on both sides of the target together with the velocity and the diameter of the projectile. Sensors behind the target detected the light from the penetration itself as well as from the debris plume. These experiments were conducted with a modular target system, which was designed to assure a constant accuracy, while significant parameters were varied. These experiments offer a new method for the determination of the projectile diameter.