Densification of MgB2 cores in iron-clad tapes

A fabrication process of iron-clad MgB2 superconducting tapes was developed by using a nano-sized precursor and highly deformed iron sheath. Quenching experiments demonstrate that the precursor fully reacts and forms MgB2 under a high pressure of 600 MPa provided by the deformed iron sheath. Very good grain connections as well as a high core density of 2.55 g cm-3 were therefore obtained. High 20 K Jc of 3.1 x 105, 1.6 x 105 and 4.9 x 104 A cm-2 at self-field, 1 and 2 T, respectively, were acquired. The results suggest that using a nano-sized precursor approach to fabricate MgB2 superconducting tape is a very promising process. (rapid communication)