High Jc YBCO superconductors prepared by the `powder melting process´

A novel method called the powder melting process (PMP) has been developed to prepare high-J_c YBCO superconductors. The YBCO conductors have been fabricated through continuous zone melting and a unidirectional solidification process using precursor powders of Y ₂BaCuO₅ (211) phase and Ba-Cu-O as starting material. The transport J_c values of the samples measured by a standard continuous DC four-probe method exceed 20000 A/cm ² at 77 K, 4 T. A YBCO conductor with dimensions of 0.2-5×0.2-5×30-100 mm³ can be fabricated by the PMP method. It is concluded that this approach will be potentially beneficial for fabricating oxide conductors with metal substrates since its melting temperature is lower than that of other melt processes by about 100°C