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arXiv · 2203.07371

Medium-Grain Niobium SRF Cavity Production Technology for Science Frontiers and Accelerator Applications

G. Myneni·Hani E. Elsayed-Ali·Md Obidul Islam·Md Nizam Sayeed·G. Ciovati·P. Dhakal·R. A. Rimmer·M. Carl·A. Fajardo·N. Lannoy·B. Khanal·T. Dohmae·A. Kumar·T. Saeki·K. Umemori·M. Yamanaka·S. Michizono·A. Yamamoto
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Abstract

We propose cost-effective production of medium grain (MG) niobium (Nb) discs directly sliced from forged and annealed billet. This production method provides clean surface conditions and reliable mechanical characteristics with sub-millimeter average grain size resulting in stable SRF cavity production. We propose to apply this material to particle accelerator applications in the science and industrial frontiers. The science applications require high field gradients (>~40 MV/m) particularly in pulse mode. The industrial applications require high Q0 values with moderate gradients (~30 MV/m) in CW mode operation. This report describes the MG Nb disc production recently demonstrated and discusses future prospects for application in advanced particle accelerators in the science and industrial frontiers.

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G. Myneni, Hani E. Elsayed-Ali, Md Obidul Islam, Md Nizam Sayeed, G. Ciovati, P. Dhakal, R. A. Rimmer, M. Carl, A. Fajardo, N. Lannoy, B. Khanal, T. Dohmae, A. Kumar, T. Saeki, K. Umemori, M. Yamanaka, S. Michizono, A. Yamamoto. 2022-03-11. Medium-Grain Niobium SRF Cavity Production Technology for Science Frontiers and Accelerator Applications. https://doi.org/10.1088/1748-0221/18/04/t04005

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