The influence of BaZrO3 on the magnetic response of (Bi,Pb): 2223 high-temperature superconductors

DC magnetization and AC complex susceptibility measurements on (Bi,Pb) : 22 23 high-temperature superconductors impurified with various amounts of BaZr O3 are presented. The results are discussed in the frame of the critical st ate model. and the values of the inter- and intragranular critical current density as well as of the field for full penetration are estimated. The val ues of the intergranular critical current density are consistent with those obtained from transport measurements. The intragranular critical current d ensity and the field for full penetration have similar values from both DC magnetization and AC susceptibility measurements. It was shown that, in the (Bi,Pb) : 2223 system. BaZrO3 impurification changes only the properties o f the intergrain matrix, while the superconducting properties of the grains are not modified.