Laser polishing of niobium for superconducting radio-frequency accelerator applications

Journal Article · Fri Aug 01 00:00:00 EDT 2014 · Phys. Rev. ST Accel. Beams

DOI:https://doi.org/10.1103/PhysRevSTAB.17.083502· OSTI ID:1150700

Zhao, Liang ^[1]; Klopf, John M. ^[1]; Reece, Charles E. ^[2]; Kelley, Michael J. ^[2]

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1. William and Mary College
2. JLAB

Interior surfaces of niobium cavities used in superconducting radio frequency accelerators are now obtained by buffered chemical polish and/or electropolish. Laser polishing is a potential alternative, having advantages of speed, freedom from noxious chemistry and availability of in-process inspection. We studied the influence of the laser power density and laser beam raster rate on the surface topography. These two factors need to be combined carefully to smooth the surface without damage. Computational modeling was used to estimate the surface temperature and gain insight into the mechanism of laser polishing. Power spectral density analysis of surface topography measurements shows that laser polishing can produce smooth topography similar to that obtained by electropolish. This is a necessary first step toward introducing laser polishing as an alternative to the currently practiced chemical polishing.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1150700
• Report Number(s): JLAB-ACC-14-1927; DOE/OR/23177-3166
• Journal Information: Phys. Rev. ST Accel. Beams, Vol. 17, Issue 08; ISSN 1098--4402
• Country of Publication: United States
• Language: English