Lessons Learned from REBCO Coil Tests Above 40 T

Wednesday 1 Apr 2026, 14:30 → 15:30 US/Pacific

Speaker: Jonathan Lee

Host: Ian Pong

Zoom: https://lbnl.zoom.us/j/5104864010

Title: Lessons Learned from REBCO Coil Tests Above 40 T

 

Abstract: REBCO coated conductors (CCs) can carry larger critical currents at higher temperatures and fields than their LTS predecessors.  However, due to their wide single-filament architecture and the introduction of defects during their complex manufacturing process, REBCO CCs exhibit unique operational phenomena that place severe limitations on their adoption into real-world magnets.  To better understand and eventually surpass these limitations, our group has tested a series of no-insulation (NI) dry-wound "Little Big Coils" (LBCs) in the 31 T resistive background field at the National High Magnetic Field Laboratory (NHMFL), the most recent of which (LBC9) generated a world-record field of 48.7 T.  Detailed materials characterizations before and after LBC tests reveal significant variations in certain conductor properties (widthwise Ic, crystallographic tilt, irreversibility strains, failure modes) that have a decisive impact on coil survivability.  This talk will discuss these effects, which vary significantly among tape lengths and even more significantly among manufacturers, and make the argument that conductor selection is at present the most important step in the design process of an ultra-high-field REBCO solenoid.

 

Biography: Jonathan Lee is a PhD student in the Larbalestier group at the National High Magnetic Field Laboratory (NHMFL) in Tallahassee, FL.  His research focuses on the production and characterization of REBCO coated conductors as they pertain to ultra-high-field solenoids and fusion devices.  He received his B.S. in Materials Science and Engineering from U.C. Berkeley in 2021 and has previously worked at Commonwealth Fusion Systems and in Berkeley Lab's ATAP division.