Ejecta from Periodical Grooves in Tin Foils under Laser-Driven Shock Loading

Laser-driven shock loading is a versatile, low destructive method to study material dynamic behaviors with an efficient repetitive rate. In these experiments, compared with the more conventional high-explosive or impact-based techniques, all the scales are reduced (few ns shock duration, a few mm planar loaded area) while the shock pressure may reach several tens of GPa. This configuration makes possible the use of many diagnostics with limited exposition to generated fragments. We present recent experiments of material ejection under laser-driven shock loading. The target is a thin plate of Tin with periodical grooves of few tens of mu m in its rear surface, in order to induce solid or liquid micro-jetting. These jets turn into a cloud of mu m-sized particles. Depending on surface roughness, the velocity and the density of the cloud vary. The density of the cloud is estimated thanks to a new high-resolution X-ray imaging with a laser-driven source; while optical shadowgraphy observes the displacement of the fastest particles. Thus, mu m-structures in the particles cloud and in the target can be revealed.