Electroplating of superconducting films of MgB2 from molten salts.pdf

Title: Electroplating of superconducting films of MgB2 from molten salts Authors: Hideki Abe,1 Kenji Yoshii,2 Kenji Nishida,1 Motoharu Imai1 1National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0047, Japan 2 Japan Atomic Energy Research Institute (JAERI), Mikadzuki, Hyogo 679-5148, Japan Correspondence should be addressed to H. A. Abstract: The superconductive boride MgB2 possesses high potential as a practical 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. 2 2 Text: The discovery of superconductivity in MgB2 has attracted extensive interest in the field of superconductor engineering because MgB2 has a very high transition temperature (Tc) of 39 K.1 In particular, a recent report on the high critical current density (Jc) of MgB2 films with an order of 105 A/cm2 at 5 K and 10 T indicated that MgB2 films possess high potential for application to power electrics.2 The conventional fabrication methods of MgB2 films are based on vacuum-evaporation, which is one of the best- established methods in the fie