EFFECT OF A LOW-AMPLITUDE SHOCK-WAVE WITH RESIDUAL PRESSURE ON HEXAGONAL BORON-NITRIDE

We have performed shockwave loading of hexagonal boron nitride under p ressures of 10.8-16 GPa in the range of initial temperatures of 20-500 degrees C in flat recovery ampoules allowing one to sustain residual pressures of similar to 1 GPa. To form a plane shock wave, a gas gun w as used. Application of a residual pressure under the action of a shoc k wave with an intensity of 16 GPa increased the yield of wurtzite bor on nitride by 4 to 5 times. This is explained on the basis of the assu mption of wurtzite formation from the amorphous phase in high-temperat ure zones of adiabatic shear in, the residual regime.