Abstract:
We have performed shock-wave loading of hexagonal boron nitride under pressures of 10.8–16 GPa in the range of initial temperatures of 20–500$^\circ$C in flat recovery ampoules allowing one to sustain residual pressures of $\sim$1 GPa. To form a plane shock wave, a gas gun was used. Application of a residual pressure under the action of a shock wave with an intensity of 16 GPa increased the yield of wurtzite boron nitride by 4 to 5 times. This explained on the basis of the assumption of wurtzite formation from the amorphous phase in high-temperature zones of adiabatic shear in the residual regime.