MICROSTRUCTURAL INVESTIGATION OF QUARTZ SUBMITTED TO ULTRA-SHORT SHOCK LOADING

A high-energy pulsed laser was used to induce very short (2 ns) pressu re pulses in quartz single crystals. The microstructure of recovered s pecimens was characterized by optical microscopy, scanning electron mi croscopy and transmission electron microscopy. Whatever the peak press ures (20-90 GPa), the shocked materials showed no shock defects (amorp hous lamellae, Brazil twins, etc.). The microstructure was dominated b y fracturing. The present study thus suggests that for very short puls e durations, quartz can be loaded at pressures well above the Hugoniot elastic limit without undergoing solid-state amorphization. The behav iour of quartz is purely elastic-brittle.