SRF2017 - List of Authors (Tian, H.)

Paper	Title	Page
THXA07	Progress with Bipolar HF-free EP and other VEP of Niobium Cavities
	H. Tian JLab, Newport News, Virginia, USA
	In collaboration with Faraday Technologies and KEK, JLab has been developing HF-free EP of Nb cavities via pulse-reversed electropolishing using several different HF-free electrolytes. Bench-scale process analytics have yielded a systematic way of characterizing the processes, identifying effective polishing parameters, and are guiding application to single and multi-cell cavities. JLab has developed a low-cost pulse control technique and implemented it in a vertical EP processing tool integrated into the JLab cleanroom suite. The polishing process dynamics for different electrolytes, the implementation in the JLab tool, and the effectiveness in application to single cell and multi-cell cavities will be reviewed. VEP development work at Cornell includes both HF-free EP and the HF-based electrolyte using novel cathode and stirring configuration.
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THPB070	Electrochemical Finishing Treatment of Nb3Sn Diffusion-coated Niobium	900
	U. Pudasaini, M.J. Kelley The College of William and Mary, Williamsburg, Virginia, USA G.V. Eremeev, M.J. Kelley, C.E. Reece, H. Tian JLab, Newport News, Virginia, USA
	Funding: Supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DEAC0506OR23177 and Office of High Energy Physics under grant DESC0014475. Nb3Sn cavities are now routinely prepared by depositing few micron thick Nb3Sn coatings on Nb cavities using tin vapor diffusion process. For the¬¬ case of niobium there is a significant improvement after electropolishing (EP), but electrochemical finishing treatment on Nb3Sn coatings has not been studied. Controlled removal of the first few layers could lead to a smoother and cleaner surface that is conducive to better RF performance. Several samples, which were coated with Nb3Sn by vapor diffusion process in a JLab sample chamber, were used to explore polishing parameters, such as I-V characteristics, removal rate, topography, etc. Preliminary results from the first runs are discussed here.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-THPB070
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Paper

Title

Page

THXA07

Progress with Bipolar HF-free EP and other VEP of Niobium Cavities

H. Tian
JLab, Newport News, Virginia, USA

In collaboration with Faraday Technologies and KEK, JLab has been developing HF-free EP of Nb cavities via pulse-reversed electropolishing using several different HF-free electrolytes. Bench-scale process analytics have yielded a systematic way of characterizing the processes, identifying effective polishing parameters, and are guiding application to single and multi-cell cavities. JLab has developed a low-cost pulse control technique and implemented it in a vertical EP processing tool integrated into the JLab cleanroom suite. The polishing process dynamics for different electrolytes, the implementation in the JLab tool, and the effectiveness in application to single cell and multi-cell cavities will be reviewed. VEP development work at Cornell includes both HF-free EP and the HF-based electrolyte using novel cathode and stirring configuration.

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPB070

Electrochemical Finishing Treatment of Nb3Sn Diffusion-coated Niobium

900

U. Pudasaini, M.J. Kelley
The College of William and Mary, Williamsburg, Virginia, USA
G.V. Eremeev, M.J. Kelley, C.E. Reece, H. Tian
JLab, Newport News, Virginia, USA

Funding: Supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DEAC0506OR23177 and Office of High Energy Physics under grant DESC0014475.
Nb3Sn cavities are now routinely prepared by depositing few micron thick Nb3Sn coatings on Nb cavities using tin vapor diffusion process. For the¬¬ case of niobium there is a significant improvement after electropolishing (EP), but electrochemical finishing treatment on Nb3Sn coatings has not been studied. Controlled removal of the first few layers could lead to a smoother and cleaner surface that is conducive to better RF performance. Several samples, which were coated with Nb3Sn by vapor diffusion process in a JLab sample chamber, were used to explore polishing parameters, such as I-V characteristics, removal rate, topography, etc. Preliminary results from the first runs are discussed here.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-THPB070

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)