SiC doped MgB2 wires in a Ti sheath prepared by stage formation

Abstract

The sintering effect between deformation steps—stage formation (SF)—of SiC doped in situ (IS)MgB2 wires deformed in a Ti sheath was studied. The samples were prepared by two-axial rolling(TAR) deformation. Titanium as a sheath material allows the use of higher sinteringtemperatures with a relatively low reaction layer with the sheath. Critical current densities(JC) were measured at temperatures of 4.2 and 15 K in external magnetic fields ranging upto 15 T. The critical temperatures, transport properties and overall porositiesof the reference and SF samples are compared and discussed. The highesttransport properties were measured for SF wires post annealed at 800 and850 °C having alsorelatively high Tc = 36.1 K, which is important for the dry-cooling operation. The results presented show that stageformation could be prospectively used for high-field and higher temperature (∼20 K) applicationsof the MgB2 superconductor.