Thermal and Electrical Behaviors of an MI HTS Insert Comprised of THEVA-SuperPower DP Coils Under High Background Magnetic Fields at 4.2 K

In this study, two metal-as-insulation (MI) REBCO double-pancake (DP) coils comprised of THEVA and SuperPower REBCO single pancake (SP) coils were constructed and assembled. A sapphire plate was inserted in between the two-single pancake (SP) assembled as a DP, while copper plates insulated by G10 were inserted between the DPs to enhance the cooling of the MI insert. The thermal and electrical characteristics were investigated under an applied external field in the range of 0 to 19 T at 4.2 K. The insert was pushed up to the quench at each field, such defining its real operating limit without damage. Its thermal stability was checked up to 10 A/s in self-field (SF) at 4.2 K. Characteristic resistance change, current-carrying performance, quench behavior, thermal stability of the MI insert is discussed.