Effect of Preliminary Deformation on the Structure and Phase Transformations of Graphite under High-Temperature Shock Compression

Abstract

The effect of preliminary shock-wave treatment of graphite on its subsequent transformations into dense modifications of carbon under high-temperature shock compression is studied. It is shown that this treatment leads to higher concentration of turbostratic stacking defects, increases the extent of lattice microdeformation along the c axis, and induces the formation of twins with three-dimensional configuration of C-C bonds on twin boundaries. These defects significantly but differently influence the phase transformations. Turbostratic defects inhibit phase transformations whereas microdeformation and twins accelerate them.