Synthesis of tungsten nanopowders and modes of their combustion and passivation

摘要

Tungsten nanopowders were synthesized by a chemical metallurgy method at 440-640 degrees C from WO3 precursors possessing different specific surfaces. The alpha-W nanopowder synthesized at 640 degrees C was not pyrophoric, while the alpha-W containing the traces of oxides obtained at 480 degrees C was pyrophoric. The temperature interval for the alpha-W synthesis was revealed as very narrow, from 470 to 490 degrees C.