Published online by Cambridge University Press: 21 February 2011
A variation of the solid-state matrix technique has been developed as aprocedure for the preparation of 2223 bismuth superconducting phases [(Bi,Pb)2Sr2Ca1-nCunO4+2n,n=3]. The adequate processing of samples of nominal compositions 2223+x0021, obtained both by this procedure and by the polymer matrix method, hasallowed the modification of the microstructure of the calcium copper excess,with no noticeable change in that of the 2223 grains. The study of the phaseevolution in the processing of the samples has shown that the formation rateof the 2223 phase is faster when the particle size of the calcium cuprate issmaller. A dependence of the intergranular superconducting properties on thesecondary phase is observed, appearing as a maximum in Jc0/μcer at x=0.2 and x=0.5 for samples prepared bysolid state matrix and polymer matrix methods, respectively.