Mechanical design of the magnet mirror structure for testing Nb3Sn sextupole coil of 45 GHz ECRIS

Abstract

The new Nb3Sn superconducting magnet system for the fourth-generation 45 GHz ECR source is under development at the Institute of Modern Physics (IMP). A mirror structure of the Nb3Sn sextupole testing coil based on an aluminum shell-based structure and bladder & key technology is used for studying the coil's mechanical, thermal and quench performance under realistic conditions. This paper describes the mechanical analyses performed to estimate the sextupole’s preload. Based on the three-dimensional finite-element mechanical model, the stress analysis for the process of assembly, cooling down, and charging is carried out. The assembly and strain measurement results of sextupole mirror structure are also introduced in this paper.