Effect of Surface Flow on Topography in Niobium Electropolishing

Conference · Tue Mar 01 04:00:00 EST 2011

OSTI ID:1032452

Electropolishing (EP) is reliably delivering improved performance of multi-celled niobium SRF accelerator cavities, attributed to the smoother surface obtained. This superior leveling is a consequence of an etchant concentration gradient layer that arises in the HF-H2SO4 electrolyte adjacent to the niobium surface during polishing. Electrolyte circulation raises the prospect that fluid flow adjacent to the surface might affect the diffusion layer and impair EP performance. In this study, preliminary bench-top experiments with a moving electrode apparatus were conducted. We find that flow conditions approximating cavity EP show no effects attributable to depletion layer disruption.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1032452
• Report Number(s): JLAB-FEL-11-1432; DOE/OR/23177-1956
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATORS
DEPLETION LAYER
DIFFUSION
ELECTRODES
ELECTROLYTES
ELECTROPOLISHING
FLUID FLOW
NIOBIUM
PERFORMANCE
POLISHING
RF SYSTEMS
SUPERCONDUCTING CAVITY RESONATORS
TOPOGRAPHY