Phase formation and microstructure of silver-sheathed B(Pb)SCCO tapes influenced by Te additive

Abstract

The influence of tellurium (Te) addition to the Bi-Pb-Sr-Ca-Cu-O (B(Pb)SCCO) system on its microstructure and phase formation is investigated. Electron probe microanalysis and scanning electron microscopy analyses show Te diffusion from the superconducting core into the silver sheath of the B(Pb)SCCO tapes. It is established that the initial Te presence in the core does not lead to any essential changes with respect to the superconducting transition temperature (Tc) and critical current density (Jc). However, Te addition appears to be a supporting factor for 2223 phase formation and crystal growth. Final Te incorporation in the silver sheath has an additional strengthening effect on the sheath that makes it more stable to external mechanical damages and gives the opportunity for better protection of the superconducting core.