Superconducting Properties of In-situ PIT MgB2 Tapes with Different Ceramic Powder

Abstract

Powder‐in‐tube PIT MgB2 tapes have been prepared through an in‐situ process using a steel sheath. Magnesium hydride MgH2 and amorphous boron powders were mixed to synthesize MgB2 superconductor. The mixed powder was encased in a steel tube and rolled into a monocore tape of about 5mm in width and 0.5mm in thickness. Different kinds of ceramic powder, i.e., SiC, TiC, WC and Si3N4 were added to the core. The addition of nanopowder, e.g. SiC and TiC, has been found to enhance appreciably the Jc in MgB2 tapes. The Ic for the 5 wt% SiC or 10 wt% TiC addition tapes reaches 100 A at 4.2 K and 7 T, which corresponds to the core Jc of higher than 10 kA/cm2. The improvement of the core Jc in higher magnetic field may results from the increase of upper critical field Hc2 due to an incorporation of ceramic nanopowder such as SiC and TiC. Furthermore, the core Jc for the hot‐pressed MgB2 tapes with SiC addition reached 40 kA/cm2 at 7 T, which is enhanced by a factor of 4 compared to that without pressing during the heat treatment.