METHOD OF PREPARING AMORPHOUS BORON NITRIDE BASED MATERIAL Russian patent published in 1998 - IPC

FIELD: preparation of boron-containing abrasive materials, more particularly manufacture of amorphous boron nitride based structure. SUBSTANCE: method comprises preparing amorphous boron nitride based material by heat treating hexagonal or turbostrate boron nitride at temperature at least 1650 C and pressure of at least 70 kbar till complete melting of stock, cooling the resulting melt by discontinuing heat supply and subsequent pressure, heat treatment being carried out in the presence of at least one crystallization inhibitor which includes oxygen-containing agents selected from group consisting of peroxides and alkali and alkaline- earth metal compounds, said agents oxidize boron nitride used as stock with inclusion of reaction products into layers of crystalline boron nitride lattice. The method makes it possible to increase efficiency of process of preparing amorphous boron nitride based material having hardness sufficient for scratching diamond. EFFECT: more efficient preparation method. 7 cl, 3 dwg, 5 ex