Phase transitions of C-70 fullerite with hexagonal closed-packed structure under shock-wave loading

摘要

Shock-induced phase transitions of C-70 fullerite with hexagonal close-packed structure were experimentally studied in the pressure range 8 to 36GPa. It was found that C-70 fullerite undergoes a series of polymorphic phase transitions under step-like shock-wave compression. The hexagonal close-packed structure of C-70 fullerite remained practically unchanged at shock pressure up to 8GPa. Shock-induced transformation of the hexagonal structure into face centered cubic structure was fixed at pressures in the range 8-23.5GPa. The depth of this transformation increases with the shock pressure. Upon further increase of the shock pressure the destruction of C-70 molecules occurs. This destruction is accompanied by the formation of graphite-like carbon.