Phase transition of KCl under shock compression

It had been reported that for potassium chloride (KCl) the B1-B2 phase transition (PT) occurs under shock and static compressions, but the measured transition points showed large scatter. In this study, Hugoniot measurement experiments were performed on KCl single crystals by the inclined-mirror method combined with use of a powder gun. The anisotropic Hugoniot elastic limits and PT points were observed. The PT points along the (100), (110) and (110) axis directions were determined as 2.5, 2.2 and 2.1 GPa, respectively. The anisotropic transition was reasonably explained in terms of the displacement mechanism along the <111> axis direction.