Effect of Fe substitution for Cu on microstructure and magnetic properties of laser floating zone (LFZ) grown Bi-2212 rods

摘要

In this paper, the laser floating zone (LFZ) technique has been used to fabricate Bi2Sr2Ca1Cu2-x Fe x O (x=0,0.01,0.03,0.05,0.1) superconducting fibers. The effects of Fe substitution on grain alignment and superconducting properties of annealed fibers were studied using SEM/EDX microanalysis in addition to phase analysis and magnetic measurements realized through XRD, M-T, and M-H loops. In the same growth conditions, higher Fe contents lead to a more compact microstructure with lower porosity but also caused the formation of poor superconducting phases followed by the decrease of T c and J cmag. No evidence of enhanced pinning capability was found in the magnetic measurements. Annealed rods indicated a weakly ferromagnetic-like behavior at relatively high doping levels.