Pure and 10wt% nano-SiC doped MgB2/Cu tapes were fabricated by using the coating and pressing method. Samples were sintered by using an in situ reaction process. It was observed that the nano-SiC doped tapes reacted significantly with the Cu sheath at 700C, while pure samples had lessser reactivity with Cu under the same conditions. However, for sintering at 667C for just 360s, the reaction with Cu was significantly reduced for nano-SiC doped samples and led to very high critical current densities of more than 1MA/cm2 in zero field at less than 10K. The JC values exceeded 105A/cm2 for 30K in zero field, 20K in 2T and less than 10K in 4T. These JC values were 1 to 2 orders of magnitude higher than those of the pure MgB2/Cu short tapes. The best reported JC values for Cu-sheathed wires and tapes were comparable to the JC values reported for MgB2/Fe tapes. These nano-SiC doped MgB2/Cu tapes also exhibited very small flux jumping at 5K. Such a high JC value and its field performance together with its possible high thermal stability made Cu-sheathed MgB2 tapes an attractive candidate for large-scale applications.

Significant Improvement of Critical Current Density in Coated MgB2/Cu Short Tapes Through Nano-SiC Doping and Short-Time in situ Reaction. X.L.Wang, Q.W.Yao, J.Horvat, M.J.Qin, S.X.Dou: Superconductor Science and Technology, 2004, 17, L21-4