Single-core MgB2/Cu and MgB2/Fe/Cu wires and tapes were made by using the powder-in-tube method and commercial MgB2 powder. This involved hydrostatic extrusion and 2-axis rolling. High-pressure post-treatments such as cold isostatic pressing, double hydrostatic extrusion and uniaxial pressing were applied. The grain connectivity, JC(B) curves, pinning in MgB2 grains, upper critical field, deformation homogeneity, compact density and preferred alignment of crystallites in the [001] (c-axis) direction were all improved by the application of various high-pressure treatments to MgB2 and its composites. Hydrostatically extruded MgB2 wires were shown to be better than rolled wires and were very promising for possible application in windings.

Effects of the High-Pressure Treatment of ex situ MgB2 Superconductors. W.Pachla, P.Kovác, R.Diduszko, A.Mazur, I.Hušek, A.Morawski, A.Presz: Superconductor Science and Technology, 2003, 16, 7-13