Preparation of NdBaCuO superconductor by zone-melting under low oxygen partial pressure

If the NdBaCuO superconductor samples were zone-melted in low oxygen partial pressure ( 1% O 2+99% Ar ), the zone-melting temperature was decreased about 120 °C from that (1060 °C) of sample melted in air. Thus the loss of liquid phase (BaCuO 2 and CuO) was reduced during the zone-melting process. The content of non-superconducting phase Nd422 in zone-melted NdBaCuO samples was clearly decreased, so was the substitution of Nd for Ba. The superconductivity of zone-melted Nd 1+ x Ba 2− x Cu 3O y prepared under low oxygen partial pressure was distinctively improved.