Pulsed wire discharge for nanosize powder synthesis

Abstract

The pulsed wire discharge, as one of the well-developed pulsed power technologies, has been successfully applied to nanosize powder production. In the demonstration experiments, the discharge was carried out with the peak current of /spl sim/10 kA, the pulse length of /spl sim/20 /spl mu/s, and the pulse energy of /spl sim/80 J. Nanosize powders of metals (Al, Fe, Cu, Mo, and Pb), metal oxides (Al/sub 2/O/sub 3/, TiO/sub 2/, Fe/sub 2/O/sub 3/, NiO, ZrO/sub 2/, SnO/sub 2/, and PbO), and metal nitrides (TiN, ZrN, Ta/sub 2/N) have been synthesized by pulsed discharge of metal wires in argon, oxygen, or nitrogen. The typical powder production rate was /spl sim/5 mg/pulse. The results of surface-area measurement have given the average powder sizes in the range of 20/spl sim/70 nm, depending on the material of the powder.