Seminar By Hubertus Weijers, 32 T Magnet Project Leader
Title: A Marriage of High and Low Temperature Superconductors: the 32 T Magnet
Abstract: An all-superconducting solenoid magnet consisting of a 15 T Low Temperature Superconductor (LTS) outer magnet and a 17 T High Temperature Superconductor (HTS) inner magnet has been tested to 32 T and found to meet all specifications. This unequivocally represents the long-awaited breakthrough from the 24-25 T limit of Nb-based Low Temperature superconducting user magnets. As a research instrument in the NHMFL milliKelvin facility, once equipped with a dilution refrigerator, this magnet will allow scientists to jump deep into the quantum realm at high magnetic field and temperatures approaching absolute zero where phase transitions in materials are no longer driven by thermal fluctuations but by quantum mechanics itself. This presentation however will present the genesis of the 32 T magnet from the early days of demonstration HTS insert magnets, to YBCO Coated Conductor test and prototype coils to the characteristics of the 32 T magnet as-built at 4.2 K. Key elements of the magnet technology, software and electronics developed specifically for this magnet will be high-lighted, like quench protection and addressing the "helium bubble problem”. Comments on “lessons learned” will be sprinkled in along the way.