Development of SHS azide technology of silicon carbide nanopowder

Abstract

The possibility of increasing the purity and yield of the SiC nanopowder using an intermediate synthesis of silicon nitride (Si3N4) by azide technology of self-propagating high-temperature synthesis based on the use of a powder of sodium azide (NaN3) as a nitriding reagent was investigated. As a result of combustion of the initial mixture of powders ‘19Si + 6NaN3 + (NH4)2SiF6 + 20’, a powdery product was obtained, consisting almost entirely of SiC (about 90%) with an admixture of Si3N4 and Si (about 5% each), and representing nanoparticles (80-150 nm) combined into agglomerates with the size up to 50 µm.