Trapped fields larger than 11 T in bulk YBa sub(2)Cu sub(3 )O sub(7-x) material

Bulk YBa sub(2)Cu sub(3)O sub(7- x) (YBCO) material with single-domain grains up to 35 mm in diameter was prepared by a modified melt-texture process. Trapped fields of 1.1 T at 77 K and of 9 T at 43 K were obtained In zinc-doped YBCO material showing a pronounced peak effect in the field dependence of the critical current density. Very high trapped fields up to 11.4 T have been achieved at 17 K in YBCO material with improved mechanical properties. The tensile strength of this material was enhanced by the addition of silver. Additionally, a stainless steel tube was used in order to strengthen the sample against the magnetic tensile stresses. For application of YBCO samples in superconducting magnetic bearings, it is difficult to magnetize the superconductor to the maximum storable field. The authors present results on magnetizing the YBCO samples by applying pulsed magnetic fields