Header and Body 3

Technology

A superconductive joint can be formed between two ends of reacted MgB2 wire by shearing the ends at acute angles and inserting them into the cavity of a stainless steel billet which is filled with a powdered mixture of magnesium and boron. A copper plug is then pressed into the cavity, partially sealing the billet. Finally, the billet is completely sealed using a ceramic paste and heat treated. In tests conducted on both short lengths of wires and test coils, magnets fabricated using this technique have been shown to be capable of quench-free operation at fields up to 90% of their critical currents, despite evidence of multiple flux jumping events. Additionally, they were shown to be capable of carrying persistent currents of up to 100 A while subjected to self-fields up to 0.94 T. This suggests that monofilament MgB2 wire is a viable material option for the fabrication of persistent-mode superconducting magnets.