Design of a Superconducting 32 T Magnet With REBCO High Field Coils

TLDR

The authors are designing and fabricating a 32 T, 32 mm cold‑bore superconducting magnet with high‑field REBCO inner coils at the NHMFL. Conductor characterization (critical current versus field, orientation, temperature, and strain), insulation studies, and a pancake‑wind, dry‑wind coil fabrication with sol‑gel insulation on stainless steel co‑wind were performed, and the magnet design—including coil configuration, conductor lengths, critical‑current fraction, copper content for protection, and winding stress—was developed, with distributed‑heater quench protection under study. Small REBCO coils were successfully fabricated and tested in a 20 T background field, demonstrating the technology’s performance.

Abstract

The design and fabrication of a 32 T, 32 mm cold bore superconducting magnet with high field REBCO inner coils is underway at the NHMFL. In support of the design, conductor characterization measurements have been made including critical current as a function of field, field orientation, temperature, and strain on conductors and joints. Various conductor and turn insulation systems were examined. The selected coil fabrication method for the 32 T magnet is pancake wind, dry wind coils with sol-gel insulation on a stainless steel co-wind. Quench protection of the REBCO coils by distributed heaters is under development. Small REBCO coils have been made and tested in a 20 T background field to demonstrate performance of the technology. The design of the 32 T magnet is described, including coil configuration and conductor lengths, fraction of critical current, selection of conductor copper content for protection, and stress in the windings.