Composition-controlled melt processing of Nd sub(1+x)Ba sub(2-x)Cu sub(3)O sub(7- delta )-based bulk material in air

Nd sub(1+x)Ba sub(2-x)Cu sub(3)O sub(7- delta ) (Nd-123) superconductors were melt-processed in air atmosphere starting from an initial precursor consisting of Nd sub(2)O sub(3), BaCuO sub(2) and CuO, or Nd-123 and BaCuO sub(2), respectively, to stabilize the process to proceed in equilibrium with compositions along the tie line Nd-123-Nd-422, both with its stoichiometric compositions. The Nd:Ba ratio was stabilized close to 1:2 and high T sub(c) values up to 96 K were achieved. As a result, J sub(c) values of 30 kA/cm super(2) (0 T) and an expressed peak effect of 10 kA/cm super(2) arises at an applied external magnetic field of 2 T at 77 K.