高い捕捉磁束密度を持つ超電導擬似永久磁石の研究

Abstract

The c-axis oriented YB_a2Cu_3O_<7-δ>(Y123) bulk superconductors have been prepared by using an optimized well established MMTG process. The sample with 0.5wt% CeO_2,additions has exhibitted the critical current density J, of 50000 A/cm^2 at 77K and 0T, when the field was applied parallel to the c-axis of the sample. The maximum trapped manetic flux density has reached 6.2 T at 25K at the center of sample surface, which is more than ten times larger than conventional Nd-Fe-B permanent magnets. This high magnetic flux density can be explained in terms of a homogeneous fine distribution of Y_2BaCuP_5 (Y211) particles embedded in the Y123 matrix.