Shock-Wave Synthesis of Novel Superhard Materials

We have used shock-wave method to synthesize the high-pressure phase of silicon nitride and diamond-like boron carbonitride. We have synthesized new silicon nitride phase as nano-powder and then consolidated the received matter into the bulk sample using the special high-quality HPHT apparatus. In the result we have obtained the bulk samples of cubic silicon nitride up to 6 mm in size. Vickers microhardness of this superhard material equals 30-50 GPa, which exceeds significantly the data of other investigations. We could not synthesize boron carbonitride. The discussion of the reasons is given