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Linear Geometry Hall Thruster with Boron Nitride and Diamond Walls

* Presented as Paper IEPC-01-39 at the 27 International Electric Propulsion Conference, Pasadena, CA, 15-19 October 2001. † Copyright © 2001 by Stanford University. Published by the Electric Rocket Propulsion Society with permission. A preliminary assessment of the sputter resistance of polycrystalline diamond plates against xenon ion bombardment is reported, and first studies of integrating diamond walls into a Hall discharge channel are performed. The polycrystalline diamond is found to have a 25% better resistance to sputtering than boron nitride, a more commonly used Hall thruster wall material. The diamond plates were integrated into a linear Hall thruster with an open electron drift. In comparison to a similar Hall thruster with boron nitride walls, the diamond containing discharge had an overall lower discharge current, but resulted in a slightly lower propellant utilization. However, unlike the case with boron nitride walls, operation with the diamond walls was limited to 200V or higher, due to the emergence of large-scale fluctuations at lower voltages.