Effect of Pb doping on the electrical properties of textured Bi-2212 superconductors

Bi2−xPbxSr2CaCu2Oy textured materials (x = 0.0, 0.2, 0.4, and 0.6) have been successfully prepared by the laser floating zone technique. Microstructure and electrical properties (JC and TC) have been clearly affected by Pb addition. From the E–I curves, slope of the transition between the superconducting and the normal state (n) at 77 K reaches a maximum of about 16 for the 0.4 Pb doped samples. This value is much higher than the typical ones for the Bi-2212 materials. Moreover, when the electrical properties of the 0.4 Pb doped samples are measured at lower temperatures (between 65 and 77 K), n values increase when the temperature is decreased. A maximum n value of 32 has been reached at 65 K which makes this material very attractive for its use as resistive fault current limiters.