Melt-textured growth and characterisation of a (Nd/Y)Ba 2Cu 3O 7−δ composite superconductor with very high critical current density

Abstract

A (Nd/Y)Ba 2Cu 3O 7−δ composite high- T c superconducting material has been fabricated in air using a melt-textured growth (MTG) technique. The material has a very high critical current density, J c ∼ 8.77 × 10 4 A cm −2 at 77 K, B = 0 T, and J c ∼ 7.59 × 10 4 A cm −2 at 77 K, B = 0.5 T, with B || c (using the modified Bean model formula) which is attributed, in part, to the partial substitution of the Nd 3+ in the Ba 2+ site. The presence of Y211 and/or Nd422 precipitates were not detected within the 123 grains indicating that these phases are not important in order to obtain samples with a high J c in this composite material.