Healing Gradient Degradation in Nb3Sn SRF Cavities Using a Recoating Method

TL;DR

This paper introduces a recoating method using vapor diffusion to repair stress-induced performance degradation in Nb3Sn SRF cavities, restoring their superconducting performance.

Contribution

The study presents a novel recoating technique with vapor diffusion to recover Nb3Sn SRF cavity performance after mechanical stress damage.

Findings

Significant performance recovery achieved after recoating.

Recoating with Sn restores superconducting properties.

Method addresses mechanical stress challenges in Nb3Sn cavities.

Abstract

Despite having advantageous superconducting properties, Nb3Sn superconducting radiofrequency (SRF) cavities still have practical challenges compared to Nb SRF cavities due to the brittle nature of Nb3Sn. Performance degradation can occur when a Nb3Sn SRF cavity experiences mechanical stresses such as during handling and tuning of the cavity. In this study, we present a potential treatment for SRF cavities that have experienced stress induced performance degradation that involves a recoating procedure. The degraded cavity is coated with a small amount of Sn using a single step vapor-diffusion methodology. Using this approach we can recover a significant portion of the lost performance of a Nb3Sn SRF cavity.