Progressive Transformation from Quartz to Amorphous Silica by Shock Pressure: Role of the α→β Transition

摘要

The transformation from crystalline α-quartz to silica glass under shock pressure is followed, in the intermediate phase where both crystalline and amorphous SiO_2 are detected, by Raman microspectrometry. Experiments are carried out on samples recovered from increasing peak pressure. The evolution of the crystalline phase is compared to the evolution of α-quartz with a thermal annealing. No observation is made for a β-phase transformation before full amorphization of the material.