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.