High Critical Current Densities in SiC Doped In-Situ MgB2 Wires Prepared by Continuous Tube Forming and Filling Technique

20 meters long length of in-situ SiC doped MgB₂/Fe, MgB₂/Nb/Cu/stainless steel (SS) mono- or MgB₂/Nb/Cu/Fe multi- filamentary wires with high critical current densities have been prepared by combining both powder in tube (PIT) and continuous tube forming & filling (CTFF) processes. Particular efforts were made in view of the optimization of the manufacturing and annealing processes of the wires. The as obtained mono- wires were sintered under a vacuum furnace and the effects of the sintering temperature on the properties of the MgB₂ wires were investigated by the analysis of XRD, SEM and the J_c measurements. The optimized sintering process was found to be 830degC for 15 minutes. It was shown that the magnetic J_c value of MgB₂/Nb/Cu/SS wire reaches 6times10⁵ A/cm² (10 K, 0 T), while the transport J_c value in this 8 at.% SiC doped MgB₂/Fe mono- filamentary wire is more than 10⁴ A/cm² at 4.2 K and a field of 11 T. The estimated J_c value approaches 10⁶ A/cm² at 4.2 K and zero field. Further enhancement of Jc in both mono- and multi- wires is expected for improving the filling density of the CTFF + PIT processing.