The fabrication and test results of hot-isostatic-pressed powder-in-tube MgB2 coils was studied. The coil properties were measured by transport and magnetization at various applied fields and temperatures. The engineering critical current (Je) value was the largest reported in powder-in-tube MgB2 wires or tapes. At 25K, the best 6-layer coil was able to generate a field of 1T at zero external field (IC>220 A, Je ~ 2.8 x 104A/cm2). At 4K, this coil generated 1.6T under an applied field of 1.25T (IC ~ 350A, Je ~ 4.5 x 104A/cm2). These magnetic fields were high enough for superconducting transformer or magnet applications. An SiC doped MgB2 single layer coil shows a promising improvement at high fields and exhibited a JC > 104A/cm2 at 7T.

Large Field Generation with a Hot Isostatically Pressed Powder-in-Tube MgB2 Coil at 25K. A.Serquis, L.Civale, J.Y.Coulter, D.L.Hammon, X.Z.Liao, Y.T.Zhu, D.E.Peterson, F.M.Mueller, V.F.Nesterenko, S.S.Indrakanti: Superconductor Science and Technology, 2004, 17, L35-7