  ctical superconducting material for power-electric products such as
superconducing tapes because of its high superconducting transition temperature
(Tc) of 39 K and its high critical current density (Jc) under magnetic fields.
Superconducting films of MgB2 have been, however, fabricated only on planar
substrates with areas of several tens of a square centimeter at the largest so
far due to the technical limitation of the conventional fabrication methods. In
this report, we describe a technique for the fabrication of MgB2 films by means
of electrolysis on molten compounds of Mg and B, that is, electroplating of
MgB2. Superconducting films of MgB2 with a Tc of 36 K were successfully
electroplated on both the planar and curved surfaces using simple
installations. The electroplating of MgB2 is expected to open a new route in
the field of superconductor engineering because of its ability to fabricate
superconducting films on large surfaces of various shapes.
