Design and Test of a 90-T Nondestructive Magnet at the Wuhan National High Magnetic Field Center

A dual-coil magnet aimed at generating 90 T (at the center of the bore) has been developed at the Wuhan National High Magnetic Field Center. This magnet consists of two coils nested coaxially. The inner coil is wound with eight layers of 2.8 mm × 4.3 mm CuNb microcomposite wire developed in China; the bore diameter is 12 mm and the outer diameter 135 mm. The outer coil was wound directly on the inner coil with 12 layers of 4 mm × 8 mm soft copper wire. All the conductor layers were reinforced by Zylon/epoxy composite. The inner and outer coils were driven by a 1.6-MJ capacitor bank and by 11 1-MJ modules, respectively. At the voltage of 15.9 kV for the inner coil and 22.9 kV for the outer coil, the inner and outer coils produced peak fields of 46.6 T and 39.7 T, respectively, which gave a total field of 86.3 T. We present details of the design, manufacture, and test of the magnet.