Properties of MgB2 wires doped with BaZrO3 nanopowder made by a modified internal magnesium diffusion process

Abstract

We report an investigation of MgB2 wires doped with BaZrO3 nanoparticles produced by a modified internal magnesium diffusion (MIMD) process. The structure of the Nb-sheathed MgB2 cores, transition temperature (Tc), critical current density (Jc) and pinning behaviour were studied and compared. Because the MgB2 cores made by MIMD process are extractable, the grain connectivity and the phase composition of the cores were also analysed. The wires exhibited very good phase purity and sharp transitions with high critical temperature (close to 38 K); the best sample of the wires under study showed enhanced Jc with almost 2 MA cm−2 at 4.2 K and 2 T. These results demonstrate the high quality of MgB2 doped with BaZrO3 nanopowder made by the MIMD method.