Evolution of microstructure during formation of Nb[sub 3]Sn superconducting phase

Nb3Sn based multi-filamentary superconducting wires with critical temperature (Tc) of 17.5 K was indigenously developed. A critical temperature (Tc) of 17.5 K was obtained. Characterization of the microstructure of the wires revealed almost complete conversion of the Nb filaments to Nb3Sn phase. The phase formed was nano-crystalline in nature and was slight hypo-stoichiometric with respect to Sn.