|
Abstract
| The enhanced racetrack model coil and racetrack model magnet constitute the current R&D Nb$_3$Sn magnets under development at CERN aiming to achieve dipole fields of 16-18 T, the design baseline of the Future Circular Collider (FCC). This article reports the mechanical behavior of their common support structure, which underwent three different levels of room-temperature preload (with the bladders and key method) and two cooldown cycles to 80 K. The structure was mounted using aluminum dummy blocks in lieu of the actual Nb$_3$Sn coils. Strain gauges were placed in the external aluminum shell, tie-rods, and dummy coils. The measurements agree well with the results of the finite-element models (FEM). This work validates the FEM and a support structure for testing Nb$_3$Sn accelerator magnets in the 16-T regime. |