Analysis of the Mechanical Behavior of a 20T Hybrid Cosθ Dipole During Quench Transients

The US Magnet Development Program is conducting research on high-field accelerator magnets targeting a bore field of 20 T for the next generation of particle colliders. To reduce the overall cost of the dipole, a viable option consists in a hybrid approach where the inner coils in the high-field region are made of High Temperature Superconductors (HTS), such as Bi-2212 or REBCO coated conductors, and the coils in the lower field region (< 16T) are made of Low Temperature Superconductors (LTS), i.e. Nb3Sn. Quench protection for high-field magnets is demanding, especially in the case of a full-scale 15 m long magnet. To mitigate these challenges, an innovative quench protection method named Energy Shift with Coupling (ESC) has been selected and integrated into the magnet design. This method requires resistive coils that are strongly magnetically coupled to the magnet coils and electrically insulated from them. In this contribution, a 20 T hybrid cos\theta dipole configuration is analyzed, investigating the stresses on the conductors during quench transients while limiting the adiabatic hot-spot temperature.