Combustion synthesis of nanostructured tungsten and its morphological study

A tungsten trioxide, zinc, and sodium chloride (WO3+3Zn+kNaCl) mixture was used as a precursor material for the manufacture of tungsten (W) nanopowders. Precursor material components were dry mixed and heated up to 450 degrees C under a constant argon gas flow to promote a combustion reaction. Combustion products were subjected to acid enrichment followed by isothermal heat treatment under hydrogen flow at temperatures ranging from 650 to 850 degrees C to reduce oxygen concentration. As-synthesized W nanopowders were characterized with respect to average particle size, particle size distribution, oxygen concentration, and phases. Under optimized reaction conditions, W particles with diameters less than 100 nm and an average interstitial oxygen concentration lower than 1.0 wt.% were obtained. (C) 2008 Elsevier B.V. All rights reserved.