Bi-2212 High-T_c Superconducting Wire Using Ni Substrate

A Cost-effective High-temperature Superconducting Wire without Ag

Abstract

Bi₂Sr₂CaCu₂O_x (Bi-2212) superconducting wires have been fabricated successfully without using Ag. Commercial Ni tapes were used for the substrate. After heat treatment in air to form a NiO layer on the Ni tape, Bi-2212 precursor was coated and heat-treated with a conventional slow cooling step. The Bi-2212 superconducting tape exhibited high critical current and critical current density: 184A and 1.2×10⁵A/cm² at 4.2K and 10T, respectively. Since Ni is much less expensive than noble metal of Ag and the whole process is simply carried out in air, the present method is promising in terms of cost.