Synthesis and transport properties of oxygen controlled melt growth textured (MixedRE)Ba2Cu3Oy (RE = Nd, Sm, Gd, Eu)

((RE)0.33Eu0.33Gd0.33)Ba2Cu3Oy bulk superconductors (RE Sm, Nd) were textured by the top seeded melt textured growth method in a reduced oxygen atmosphere, so-called oxygen controlled melt growth (OCMG). Large single domains of diameter 16 mm were successfully grown. Their microstructure and their magnetic and transport properties were investigated and compared. The resistive transition was found around 88 K, which is not the optimal Tc of 95 K that could be obtained on a small re-oxygenated sample cut out from the bulk. Transport measurements were also performed on these samples at various temperature from 77 to 88 K. In the case of Nd0.33Eu0.33Gd0.33Ba2Cu3Oy (NEG) composition, the angular dependence of the critical current densities along the (a,b) planes as a function of magnetic field was also measured. Transport critical current densities higher than 50 000 A cm-2 are reached at 77 K and up to 2 T, corresponding to the nominal critical currents of 90 A injected through sections less than 0.25 mm2 reproducibly. This confirms the high quality of the single domain obtained with a well controlled process, evidencing that mixing of rare earth is a very promising composition for transport and high-field applications