We designed and fabricated two types of composite wires with 6
MgB2
filaments. One is a Cu-sheathed Nb-barrier wire and the other is a CuNi-sheathed
Ta-barrier wire. The transverse-field losses of the trial wires were measured with a
standardized pickup coil system in liquid helium. We evaluated the observed AC losses
using two structural models, a multifilament conductor model and a hollow-cylindrical one.
For the CuNi-sheathed Ta-barrier wire, the AC loss property can be explained by
the usual model of multifilament conductors. Further reductions in AC loss can
be expected by making the filaments thinner. For the Cu-sheathed Nb-barrier
wire, theoretical considerations suggest the multifilament structure behaves as a
hollow-cylindrical superconductor in the AC loss property. Thus, we need to pay
particular attention to designing the barrier material for reduction in the AC
loss.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.