Nitride nanopowders by azide SHS technology

Abstract

Azide SHS technology with NaN3 powder as a nitriding agent was used to fabricate TiN–BN, AlN–BN, and Si3N4–TiN nanopowders using Nа2TiF6, (NH4)2TiF6, KBF4, NH4BF4, Nа3AlF6, AlF3, Na2SiF6, and (NH4)2SiF6 as precursors. Mixtures of the above salts with sodium azide NaN3 readily burned in an SHS reactor to yield agglomerated nanosized or fine target powders. Phase composition of combustion products not always corresponded to expectations and often contained insoluble byproducts. Reported are optimal green compositions and procedures that afford the preparation of target TiN–BN, AlN–BN, and Si3N4–TiN nanopowders free of byproducts.