Mirror-smooth surfaces and repair of defects in superconducting RF cavities by mechanical polishing

Mechanical techniques for polishing the inside surface of niobium superconducting radio-frequency (SRF) cavities have been systematically explored. By extending known techniques to fine polishing, mirror-like finishes were produced, with 8 × 109 at 35 MV m−1, which is the specification for the International Linear Collider. Future optimization of the process and pathways for eliminating requirements for acid processing are also discussed.

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