Project Title:

Porous Cathode for Alkali Propellant MPD Thrusters

92-1-11.10-6551A                                                   NAS07-1224
Porous Cathode for Alkali Propellant MPD Thrusters
Thermacore, Inc.
780 Eden Road
Lancaster, PA  17601
William G. Anderson                                  (717-569-6551)

Abstract:

     This project will develop a porous cathode that will
eliminate cathode erosion as the mission-limiting factor of alkali
propellant MPD thrusters. A porous cathode delivers lithium
directly to the cathode tip, lowering the effective work function
of the cathode surface. During start-up, the arc spots vaporize
the lithium instead of heating and vaporizing tungsten. During
steady state, the increased lithium concentration near the surface
increases backscatter and reduces tungsten evaporation.

Potential Commercial Application:

Potential Commercial Applications:  If successful, this concept
will remove cathode erosion as a factor for limiting the duration
of space missions.

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