Properties of transport current for polycrystalline tbcco superconductor with high density

The measurements of current-voltage characteristic at various temperatures and applied fields have shown that resistanceless currents persist at fields up to 8T before flux flow resistance is detected for polycrystalline Tl2Ba2 Ca2Cu3-O10 (TBCCO) superconductor with high density. Significant improvement of the grainboundary properties and possibility of high ability of transport current have also been explored. The microstructure examination and magnetization measurements support strongly these results.