The direct application of long life, high current hollow cathodes is that of supporting NASA missions involving high power electric propulsion. This includes those high power missions, which are envisioned to support human operations in space. Under this phase I effort, contact will be made with hollow cathode stake holders to fully assess the impact of successful implementation of this technology. In particular, findings will be directly communicated to NASA. Successful embodiments will be sent to NASA for validation testing.
The presence of energetic ions is not germane to high current cathodes though as was observed in the NSTAR long duration test. In this regard, the technology developed from this effort would also eliminate this failure mechanism for cathodes presumably over essentially all operating ranges. The technology therefore is generally applicable to Hall and ion thrusters used for government and commercial satellite station keeping. Indeed, the technology would be a life extender for commercial sector satellite makers. Commercial GSO market expects to launch of order 21 satellites per year and commercial NGSO of order 13 launches per year over the next 10 years. Electric propulsion is an onboard propulsion option for these vehicles and in this regard there is a stable market for this cathode life extension technology. The approach investigated here does not constitute a significant modification to the cathode rather it's essentially a retrofit featuring a novel, adaptable technology. This would in turn save costs to satellite venders by reducing development time of long life cathodes based on this technology proposed. Additionally, the long life cathodes can also be used in commercial materials processing application such as vacuum plasma assisted CVD coatings. Hollow cathodes are desirable for such applications because of the associated high plasma densities.
More »