The Effect of Filament Diameter on Je in High Filament Count Bi2212/Ag Round Wire

In this study, we investigated the effect of filament size on J(e) for high filament count Bi2212 round wire conductors partial melt processed with T-max between 882 and 890 degrees C in pure oxygen. The filament size that produced maximum J(e) was between 12 and 15 mu m depending on conductor design and T-max. When the filament size was below 12 mu m the filaments were unstable during partial melt processing leading to a break-up in the structure of the filament array and low J(e).This effect is attributed the formation of interconnects between filaments which leads to coarsening driven by a reduction in interfacial surface energy.