Current densities of thin filament MgB2/Ti/GlidCop® wire

Fine-filamentary MgB2/Ti/GlidCop wire has been produced by an in situ process. Hydrostatic extrusion, drawing and two-axis rolling were used for wire deformation up to the size of 0.2 x 0.2 mm(2). An averaged filament size of 7.6-14 mu m was obtained for two-axis rolled wire and tape, which are the smallest MgB2 filaments known so far. Very short annealing periods (3-7 min) were used for the thinnest filaments, resulting in a critical current density of approximate to 12 000 A cm(-2) at 8 T and 4.2 K. The results presented demonstrate the ability to prepare uniform approximate to 10 mu m size and high current density filamentary MgB2 wires in nonmagnetic sheaths, which can be applied for DC and AC coils.