90 T Insert Magnet Performance

1. 100T 90 T Insert Magnet Performance Chuck Swenson, Dwight Rickel NHMFL Pulsed Field Facility Los Alamos National Laboratory

2. Background on the 100 T Magnet Project (National High Magnetic Field Laboratory, Los Alamos Pulsed Facility) The National High Magnetic Field Laboratories 100 T Multi-shot Magnet has completed phase one commissioning to 85 Tesla. The US Department of Energy and the National Science Foundation supported the magnet system's development and construction. The magnet system is the culmination of 10 years of efforts by DOE and NSF design teams.  Several significant advances in materials processing and engineering design have made this system a reality. The peak field of the magnet will be gradually incremented up to 100 T as operating experience is gained. This 100 T system is the fourth major large magnet project to be delivered by the NHMFL. The magnet enters the science user program providing the highest magnetic fields ever produced non-destructively.Magnetic fields provide one of the cleanest experimental tools to investigate condensed matter systems. In high magnetic field research, time at peak field is of essence. The newly commissioned magnet generates pulses on the "millisecond (ms)” time scale. The Multi-shot/millisecond magnet will be the first in the world open to the scientific community able to deliver pulse intensities of up to 85 T in the ms time scale. This new NHMFL capability is positioned to expand frontiers in high magnetic field research. One of our goals is developing thermodynamic measurements in the "ms" time range, taking full advantage not only of the peak field, but also the time at peak field. Exploring new frontiers of extreme high magnetic fields will help our understanding of complex phase transitions in matter. This magnet will indeed provide a tunable electronic energy scale, and enable a tunable nano-size length scale in experimental systems.

3. General Overview of Insert Geometry Upper Electrical Interconnects LN Bucket Bus Kapton Glass/Epoxy Bumpers Joints Frame Plates Windings Burst Disk Vent

4. Quantitative Description of Insert Operational Attributes of 90 T Insert Magnet Parameter Value Insert Field Generated (T) 53.0 Outer Coil Set Operational Field (T) 35.0 Outer Coil Set Field During Pulse (T) 32.0 Combined Field for Science Pulse (T) 85.0 Magnet Bore Diameter (mm) 15.5 Magnet Inductance at 20 Hz (µH) 835 Current Generating 51.9 T (kA) 38.4 Field Energy at 53.0 T (MJ) 0.616 Bank Capacitance (mF) 15.2 Bank Voltage (kV) 14.0 Bank Inductance (µH) 200 Bank Energy (MJ) 1.49 Pulse Rise Time (ms) 5.33 Pulse Decay Time (ms) ~7 Nominal Cool Down Time (min.) 60 - 90 Conductor Material in Coil Cu-Nb Conductor Dimension (mm) 3.0 x 5.8 Conductor Insulation Kapton + Zylon Serving Structure of Insert Coil Outside Diameter (mm) 195.5 Assembly Process Poly-Layer Number of Layers 8 Number of Turns/Layer 26 Reinforcement Structure Composite Hybrid Metal MP35N Fiber Composite Zylon HM Axial Structural Components G-10 Axial External Support Tube “Stinger” 316L:SS

5. Status and Future Development • The insert/outsert magnet system has now delivered in excess of 50 pulses above 85 T. This operational intensity is presently unequaled providing NHMFL users a unique scientific research platform. • Future insert development work will focus on the adoption new materials and the development of a better understanding of the requirements for high field operation. • The engineering design of this system can be best described as an effort to properly understand and correctly implement new materials as they are developed. • The most probable future design upgrade for the insert assembly will entail the adoption of a duplex powered coil assembly. • We will examine the optimal interface between the generator powered outsert magnet and a larger duplex powered insert magnet.