Mechanical Property Evaluation of CSMC Armour and Helium Inlet under Steady-State Operation

To verify the mechanical safety of the armour and helium inlet of the China Fusion Engineering Test Reactor (CFETR) Central Solenoid Model Coil (CSMC) under multi-physics coupling fields during steady-state operation, this study adopted the electromagnetic-structural indirect coupling method, complying with ASME analytical design criteria and ITER magnet design specifications. A simplified electromagnetic model of CSMC was established via ANSYS Maxwell, and a current filament mapping approach was employed to achieve complete and accurate transfer of electromagnetic forces to the structural model. Static structural analysis using ANSYS was conducted to obtain the stress distribution of key components under multi-field coupling. Evaluation based on stress linearization results and ITER stress thresholds demonstrated that the Nb₃Sn armour and helium inlet fully meet safety requirements, while the NbTi armour complies with design criteria after cold working hardening treatment. This study confirms that the existing design of CSMC armour and racetrack-shaped helium inlet can withstand the strength demands of cryogenic multi-coupling fields, providing critical technical support for the engineering application of CFETR CSMC and a valuable reference for the cooling interface design of Cable-in-Conduit Conductors (CICC) in large-scale superconducting magnets.