TEXTURE AND ANISOTROPY OF Jc OF EX SITU MgB2/Fe MONO-FILAMENTGRY TAPES
Texture and Anisotropy of Jc of ex situ MgB2/Fe Mono—Filamentary Tapes

The ex situ MgB2/Fe mono-filamentary tapes have been prepared by powder in tube (PIT) technique starting from MgB2 powders with different sizes. The critical current densities, Jc, of the tapes have been measured at various magnetic fields and different temperatures. It was found that the anisotropy of Jc is influenced significantly by the starting MgB2 powder grain size. The recrystallized grain size of the annealed MgB2 core is increased with increasing of starting powder size. XRD analysis of the MgB2 filaments removing the Fe sheath showed that it existed slight stronger texture at the interface between MgB2/Fe sheath than that in the centre of the MgB2 filaments. The correlation among the starting powder size, texture and anisotropy of Jc was discussed.