| A low aspect ratio electrothermal gun for metal plasma vapor discharge and ceramic nanopowder production
Kyoungjin Kim
The Journal of Mechanical Science and Technology, vol. 22, no. 7, pp.1408-1416, 2008
Abstract : Traditionally, the electrothermal gun design has the bore of a large aspect ratio; however, a low aspect ratio design
with a shorter bore length has been employed for efficient production of metal plasma vapors and synthesis of nanomaterials.
In a comparison of the arc resistance-current relationship, a low aspect ratio design is found to exhibit distinctively
different characteristics compared to a high aspect ratio design, and this trend is explained by the scaling law of
plasma properties including theory of plasma electrical conductivity. A one-dimensional isothermal model has been
applied to the present experiments to confirm the scaling laws, and it was found that the present modification of the
electrothermal gun is able to produce fully ionized metal plasma vapor, while the plasma vapor produced in a conventional
design is partially ionized. Also, by reacting metal plasma vapors with the controlled gases in the reaction chamber,
nanoscale materials such as aluminum oxide, aluminum nitride, and titanium oxide were synthesized successfully.
Keyword : Electrothermal gun; Metal plasma vapors; Plasma vapor discharge; Nanomaterial synthesis |
