Operation of a Segmented Hall Thruster with Low-sputtering Carbon-velvet Electrodes
Authors: Y. Raitses, D. Staack, A. Dunaevsky, and N.J. Fisch
Date of PPPL Report: December 2005
Submitted to: Journal of Applied Physics
Carbon fiber velvet material provides exceptional sputtering resistance properties exceeding those for graphite and carbon composite materials. A 2 kW Hall thruster with segmented electrodes made of this novel material was operated in the discharge voltage range of 200-700 V. The arcing between the floating velvet electrodes and the plasma was visually observed, especially during the initial conditioning time, which lasts for an hour. The comparison of voltage-versus current and plume characteristics of the Hall thruster with and without segmented electrodes indicates that the magnetic insulation of the segmented thruster improves with the discharge voltage at a fixed magnetic field. The observations reported here also extend the regimes wherein the segmented Hall thruster can have a narrower plume than that of the conventional non-segmented thruster.