Isothermal melt processing of BI-2212 wires and tapes

Isothermal melt processing has been used to produce high critical currents (I-c's) and current densities (J(c)'s) in Bi2Sr2CaCu2Oy round wires and flat tapes, I-c's and J(c)'s of 225 A and 80 kA/cm(2) have been obtained in short length, monocore wires. However, voids and other macroscopic defects have limited performance over longer lengths. Isothermally melt processed tapes have yielded I-c and J(c) values up to 341 A and 245 kA/cm(2) although performance over longer lengths is somewhat reduced. A test coil made from 0.5 m of tape yielded I-c and J(c) values of 208 A and 153 kA/cm(2), respectively.