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

摘要

Bi_(2-x)Pb_xSr_2CaCu_2O_y textured materials (x=0.0,0.2,0.4, and 0.6) have been successfully prepared by the laser floating zone technique. Microstruc-ture and electrical properties (J_C and T_c) 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.