Pulsed power application to produce silver nanopowders

With the advent of nanotechnology there has been a soaring need for a mass production process for the production of silver (Ag) nanosized powders for various industry applications such as the cosmetics, the electrodes for MLCC (MultiLayer Ceramic Capacitors) and silver fiber. A pulsed power based electric wire explosion (hereafter referred as EWE) can be a candidate to meet the demand. This technology can be traced back as far as 1774. Nairne was engaged in metallic wires sputtering with electrical explosion and in the middle of 70s in the USSR the research program of ultra fine powder was formed. This work describes an EWE system with a pulsed power system to produce silver powder for industry applications. The system is capable of the generation of spherical and highly crystalline silver powders with wide range of properties of mean diameter and particle size distribution. Powders with mean diameters of ranging from 0.1/spl sim/0.3/spl mu/m and 5/spl sim/6/spl mu/m are produced by changing electrical parameters. This shows the capability of particle size control of the process. The system is pollution free process as no chemical process is involved. The process is described with respect to the following characteristics: Electrical parameter versus wire length and diameter, SEM (Scanning Electron Microscopy) images of the Ag powders, phase analysis by XRD (X-Ray Diffraction), particle size distribution by PSA (Particle Size Analyzer).