| Title |
Energetic Copper Coating on Stainless Steel Power Couplers for SRF Application |
| Authors |
- I. Irfan, S.F. Chapman, M. Krishnan, K.M. Velas
AASC, San Leandro, California, USA
- W. Kaabi
LAL, Orsay, France
|
| Abstract |
Delivering RF power from the outside (at room temperature) to the inside of SRF cavities (at ~4 K temperature), requires a power coupler to be thermally isolating, while still electrically conducting on the inside. Stainless steel parts that are coated on the insides with a few skin depths of copper can meet these conflicting requirements. The challenge has been the adhesion strength of copper coating on stainless steel coupler parts when using electroplating methods. These methods also require a nickel flash layer that is magnetic and can therefore pose problems. Alameda Applied Sciences Corporation (AASC) uses Coaxial Energetic Deposition (CED) from a cathodic arc plasma to grow copper films directly on stainless steel coupler parts with no Ni layer and no electrochemistry. The vacuum arc plasma consists of ~100 eV Cu ions that penetrate a few monolayers into the stainless steel substrate to promote growth of highly adhesive films with crystalline structure. Adhesion strength and coating quality of copper coatings on complex stainless steel tubes, bellows, mock coupler parts and an actual Tesla Test Facility (TTF) type coupler part, are discussed.
|
| Footnotes & References |
* Adhesion and Cu quality testing were done for us by the Fermilab Technical Division, Superconducting RF Development Department |
| Funding |
This research is supported by the US DOE via and SBIR grant: DE-SC0009581 |
| Paper |
download THPB083.PDF [1.077 MB / 5 pages] |
| Conference |
SRF2015, Whistler, BC, Canada |
| Series |
International Conference on RF Superconductivity (17th) |
| Proceedings |
Link to full SRF2015 Proccedings |
| Session |
Poster Session |
| Date |
17-Sep-15 14:30–17:40 |
| Main Classification |
SRF Technology - Ancillaries |
| Keywords |
SRF, cathode, plasma, laser, ion |
| Publisher |
JACoW, Geneva, Switzerland |
| Editors |
Robert E. Laxdal (TRIUMF, Vancouver, BC, Canada); Jana Thomson (TRIUMF, Vancouver, BC, Canada); Volker RW Schaa (GSI, Darmstadt, Germany) |
| ISBN |
978-3-95450-178-6 |
| Published |
December 2015 |
| Copyright |
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