Microstructures, Jc and flux pinning in Ag─Clad Bi─Pb─Sr─Ca─Cu─O wires

High critical current density (Jc) and improved Jc-magnetic field dependence have been achieved in Ag-clad (Bi, Pb)2Sr2Ca2Cu3O10+x (2223) wires. Complex AC susceptibility measurements under DC magnetic fields have revealed that the irreversibility temperature scaled with the applied field according to H1/3, in contrast with YBa2Cu3O7-x but in accordance with bulk Bi-based and Tl-based materials. The presence of a fraction of highly dispersed 2212 appears to have a beneficial effect on flux pinning.